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1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @settitle @sc{gnu} Binary Utilities
4 @finalout
5 @synindex ky cp
6
7 @c man begin INCLUDE
8 @include bfdver.texi
9 @c man end
10
11 @copying
12 @c man begin COPYRIGHT
13 Copyright @copyright{} 1991-2015 Free Software Foundation, Inc.
14
15 Permission is granted to copy, distribute and/or modify this document
16 under the terms of the GNU Free Documentation License, Version 1.3
17 or any later version published by the Free Software Foundation;
18 with no Invariant Sections, with no Front-Cover Texts, and with no
19 Back-Cover Texts. A copy of the license is included in the
20 section entitled ``GNU Free Documentation License''.
21
22 @c man end
23 @end copying
24
25 @dircategory Software development
26 @direntry
27 * Binutils: (binutils). The GNU binary utilities.
28 @end direntry
29
30 @dircategory Individual utilities
31 @direntry
32 * addr2line: (binutils)addr2line. Convert addresses to file and line.
33 * ar: (binutils)ar. Create, modify, and extract from archives.
34 * c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols.
35 * cxxfilt: (binutils)c++filt. MS-DOS name for c++filt.
36 * dlltool: (binutils)dlltool. Create files needed to build and use DLLs.
37 * nlmconv: (binutils)nlmconv. Converts object code into an NLM.
38 * nm: (binutils)nm. List symbols from object files.
39 * objcopy: (binutils)objcopy. Copy and translate object files.
40 * objdump: (binutils)objdump. Display information from object files.
41 * ranlib: (binutils)ranlib. Generate index to archive contents.
42 * readelf: (binutils)readelf. Display the contents of ELF format files.
43 * size: (binutils)size. List section sizes and total size.
44 * strings: (binutils)strings. List printable strings from files.
45 * strip: (binutils)strip. Discard symbols.
46 * elfedit: (binutils)elfedit. Update the ELF header of ELF files.
47 * windmc: (binutils)windmc. Generator for Windows message resources.
48 * windres: (binutils)windres. Manipulate Windows resources.
49 @end direntry
50
51 @titlepage
52 @title The @sc{gnu} Binary Utilities
53 @ifset VERSION_PACKAGE
54 @subtitle @value{VERSION_PACKAGE}
55 @end ifset
56 @subtitle Version @value{VERSION}
57 @sp 1
58 @subtitle @value{UPDATED}
59 @author Roland H. Pesch
60 @author Jeffrey M. Osier
61 @author Cygnus Support
62 @page
63
64 @tex
65 {\parskip=0pt \hfill Cygnus Support\par \hfill
66 Texinfo \texinfoversion\par }
67 @end tex
68
69 @vskip 0pt plus 1filll
70 @insertcopying
71 @end titlepage
72 @contents
73
74 @node Top
75 @top Introduction
76
77 @cindex version
78 This brief manual contains documentation for the @sc{gnu} binary
79 utilities
80 @ifset VERSION_PACKAGE
81 @value{VERSION_PACKAGE}
82 @end ifset
83 version @value{VERSION}:
84
85 @iftex
86 @table @code
87 @item ar
88 Create, modify, and extract from archives
89
90 @item nm
91 List symbols from object files
92
93 @item objcopy
94 Copy and translate object files
95
96 @item objdump
97 Display information from object files
98
99 @item ranlib
100 Generate index to archive contents
101
102 @item readelf
103 Display the contents of ELF format files.
104
105 @item size
106 List file section sizes and total size
107
108 @item strings
109 List printable strings from files
110
111 @item strip
112 Discard symbols
113
114 @item elfedit
115 Update the ELF header of ELF files.
116
117 @item c++filt
118 Demangle encoded C++ symbols (on MS-DOS, this program is named
119 @code{cxxfilt})
120
121 @item addr2line
122 Convert addresses into file names and line numbers
123
124 @item nlmconv
125 Convert object code into a Netware Loadable Module
126
127 @item windres
128 Manipulate Windows resources
129
130 @item windmc
131 Generator for Windows message resources
132
133 @item dlltool
134 Create the files needed to build and use Dynamic Link Libraries
135 @end table
136 @end iftex
137
138 This document is distributed under the terms of the GNU Free
139 Documentation License version 1.3. A copy of the license is included
140 in the section entitled ``GNU Free Documentation License''.
141
142 @menu
143 * ar:: Create, modify, and extract from archives
144 * nm:: List symbols from object files
145 * objcopy:: Copy and translate object files
146 * objdump:: Display information from object files
147 * ranlib:: Generate index to archive contents
148 * size:: List section sizes and total size
149 * strings:: List printable strings from files
150 * strip:: Discard symbols
151 * c++filt:: Filter to demangle encoded C++ symbols
152 * cxxfilt: c++filt. MS-DOS name for c++filt
153 * addr2line:: Convert addresses to file and line
154 * nlmconv:: Converts object code into an NLM
155 * windmc:: Generator for Windows message resources
156 * windres:: Manipulate Windows resources
157 * dlltool:: Create files needed to build and use DLLs
158 * readelf:: Display the contents of ELF format files
159 * elfedit:: Update the ELF header of ELF files
160 * Common Options:: Command-line options for all utilities
161 * Selecting the Target System:: How these utilities determine the target
162 * Reporting Bugs:: Reporting Bugs
163 * GNU Free Documentation License:: GNU Free Documentation License
164 * Binutils Index:: Binutils Index
165 @end menu
166
167 @node ar
168 @chapter ar
169
170 @kindex ar
171 @cindex archives
172 @cindex collections of files
173
174 @c man title ar create, modify, and extract from archives
175
176 @smallexample
177 ar [-]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
178 ar -M [ <mri-script ]
179 @end smallexample
180
181 @c man begin DESCRIPTION ar
182
183 The @sc{gnu} @command{ar} program creates, modifies, and extracts from
184 archives. An @dfn{archive} is a single file holding a collection of
185 other files in a structure that makes it possible to retrieve
186 the original individual files (called @dfn{members} of the archive).
187
188 The original files' contents, mode (permissions), timestamp, owner, and
189 group are preserved in the archive, and can be restored on
190 extraction.
191
192 @cindex name length
193 @sc{gnu} @command{ar} can maintain archives whose members have names of any
194 length; however, depending on how @command{ar} is configured on your
195 system, a limit on member-name length may be imposed for compatibility
196 with archive formats maintained with other tools. If it exists, the
197 limit is often 15 characters (typical of formats related to a.out) or 16
198 characters (typical of formats related to coff).
199
200 @cindex libraries
201 @command{ar} is considered a binary utility because archives of this sort
202 are most often used as @dfn{libraries} holding commonly needed
203 subroutines.
204
205 @cindex symbol index
206 @command{ar} creates an index to the symbols defined in relocatable
207 object modules in the archive when you specify the modifier @samp{s}.
208 Once created, this index is updated in the archive whenever @command{ar}
209 makes a change to its contents (save for the @samp{q} update operation).
210 An archive with such an index speeds up linking to the library, and
211 allows routines in the library to call each other without regard to
212 their placement in the archive.
213
214 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
215 table. If an archive lacks the table, another form of @command{ar} called
216 @command{ranlib} can be used to add just the table.
217
218 @cindex thin archives
219 @sc{gnu} @command{ar} can optionally create a @emph{thin} archive,
220 which contains a symbol index and references to the original copies
221 of the member files of the archive. This is useful for building
222 libraries for use within a local build tree, where the relocatable
223 objects are expected to remain available, and copying the contents of
224 each object would only waste time and space.
225
226 An archive can either be @emph{thin} or it can be normal. It cannot
227 be both at the same time. Once an archive is created its format
228 cannot be changed without first deleting it and then creating a new
229 archive in its place.
230
231 Thin archives are also @emph{flattened}, so that adding one thin
232 archive to another thin archive does not nest it, as would happen with
233 a normal archive. Instead the elements of the first archive are added
234 individually to the second archive.
235
236 The paths to the elements of the archive are stored relative to the
237 archive itself. For security reasons absolute paths and paths with a
238 @code{/../} component are not allowed.
239
240 @cindex compatibility, @command{ar}
241 @cindex @command{ar} compatibility
242 @sc{gnu} @command{ar} is designed to be compatible with two different
243 facilities. You can control its activity using command-line options,
244 like the different varieties of @command{ar} on Unix systems; or, if you
245 specify the single command-line option @option{-M}, you can control it
246 with a script supplied via standard input, like the MRI ``librarian''
247 program.
248
249 @c man end
250
251 @menu
252 * ar cmdline:: Controlling @command{ar} on the command line
253 * ar scripts:: Controlling @command{ar} with a script
254 @end menu
255
256 @page
257 @node ar cmdline
258 @section Controlling @command{ar} on the Command Line
259
260 @smallexample
261 @c man begin SYNOPSIS ar
262 ar [@option{-X32_64}] [@option{-}]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
263 @c man end
264 @end smallexample
265
266 @cindex Unix compatibility, @command{ar}
267 When you use @command{ar} in the Unix style, @command{ar} insists on at least two
268 arguments to execute: one keyletter specifying the @emph{operation}
269 (optionally accompanied by other keyletters specifying
270 @emph{modifiers}), and the archive name to act on.
271
272 Most operations can also accept further @var{member} arguments,
273 specifying particular files to operate on.
274
275 @c man begin OPTIONS ar
276
277 @sc{gnu} @command{ar} allows you to mix the operation code @var{p} and modifier
278 flags @var{mod} in any order, within the first command-line argument.
279
280 If you wish, you may begin the first command-line argument with a
281 dash.
282
283 @cindex operations on archive
284 The @var{p} keyletter specifies what operation to execute; it may be
285 any of the following, but you must specify only one of them:
286
287 @table @samp
288 @item d
289 @cindex deleting from archive
290 @emph{Delete} modules from the archive. Specify the names of modules to
291 be deleted as @var{member}@dots{}; the archive is untouched if you
292 specify no files to delete.
293
294 If you specify the @samp{v} modifier, @command{ar} lists each module
295 as it is deleted.
296
297 @item m
298 @cindex moving in archive
299 Use this operation to @emph{move} members in an archive.
300
301 The ordering of members in an archive can make a difference in how
302 programs are linked using the library, if a symbol is defined in more
303 than one member.
304
305 If no modifiers are used with @code{m}, any members you name in the
306 @var{member} arguments are moved to the @emph{end} of the archive;
307 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
308 specified place instead.
309
310 @item p
311 @cindex printing from archive
312 @emph{Print} the specified members of the archive, to the standard
313 output file. If the @samp{v} modifier is specified, show the member
314 name before copying its contents to standard output.
315
316 If you specify no @var{member} arguments, all the files in the archive are
317 printed.
318
319 @item q
320 @cindex quick append to archive
321 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
322 @var{archive}, without checking for replacement.
323
324 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
325 operation; new members are always placed at the end of the archive.
326
327 The modifier @samp{v} makes @command{ar} list each file as it is appended.
328
329 Since the point of this operation is speed, implementations of
330 @command{ar} have the option of not updating the archive's symbol
331 table if one exists. Too many different systems however assume that
332 symbol tables are always up-to-date, so @sc{gnu} @command{ar} will
333 rebuild the table even with a quick append.
334
335 Note - @sc{gnu} @command{ar} treats the command @samp{qs} as a
336 synonym for @samp{r} - replacing already existing files in the
337 archive and appending new ones at the end.
338
339 @item r
340 @cindex replacement in archive
341 Insert the files @var{member}@dots{} into @var{archive} (with
342 @emph{replacement}). This operation differs from @samp{q} in that any
343 previously existing members are deleted if their names match those being
344 added.
345
346 If one of the files named in @var{member}@dots{} does not exist, @command{ar}
347 displays an error message, and leaves undisturbed any existing members
348 of the archive matching that name.
349
350 By default, new members are added at the end of the file; but you may
351 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
352 placement relative to some existing member.
353
354 The modifier @samp{v} used with this operation elicits a line of
355 output for each file inserted, along with one of the letters @samp{a} or
356 @samp{r} to indicate whether the file was appended (no old member
357 deleted) or replaced.
358
359 @item s
360 @cindex ranlib
361 Add an index to the archive, or update it if it already exists. Note
362 this command is an exception to the rule that there can only be one
363 command letter, as it is possible to use it as either a command or a
364 modifier. In either case it does the same thing.
365
366 @item t
367 @cindex contents of archive
368 Display a @emph{table} listing the contents of @var{archive}, or those
369 of the files listed in @var{member}@dots{} that are present in the
370 archive. Normally only the member name is shown; if you also want to
371 see the modes (permissions), timestamp, owner, group, and size, you can
372 request that by also specifying the @samp{v} modifier.
373
374 If you do not specify a @var{member}, all files in the archive
375 are listed.
376
377 @cindex repeated names in archive
378 @cindex name duplication in archive
379 If there is more than one file with the same name (say, @samp{fie}) in
380 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
381 first instance; to see them all, you must ask for a complete
382 listing---in our example, @samp{ar t b.a}.
383 @c WRS only; per Gumby, this is implementation-dependent, and in a more
384 @c recent case in fact works the other way.
385
386 @item x
387 @cindex extract from archive
388 @emph{Extract} members (named @var{member}) from the archive. You can
389 use the @samp{v} modifier with this operation, to request that
390 @command{ar} list each name as it extracts it.
391
392 If you do not specify a @var{member}, all files in the archive
393 are extracted.
394
395 Files cannot be extracted from a thin archive.
396
397 @item --help
398 Displays the list of command line options supported by @command{ar}
399 and then exits.
400
401 @item --version
402 Displays the version information of @command{ar} and then exits.
403
404 @end table
405
406 A number of modifiers (@var{mod}) may immediately follow the @var{p}
407 keyletter, to specify variations on an operation's behavior:
408
409 @table @samp
410 @item a
411 @cindex relative placement in archive
412 Add new files @emph{after} an existing member of the
413 archive. If you use the modifier @samp{a}, the name of an existing archive
414 member must be present as the @var{relpos} argument, before the
415 @var{archive} specification.
416
417 @item b
418 Add new files @emph{before} an existing member of the
419 archive. If you use the modifier @samp{b}, the name of an existing archive
420 member must be present as the @var{relpos} argument, before the
421 @var{archive} specification. (same as @samp{i}).
422
423 @item c
424 @cindex creating archives
425 @emph{Create} the archive. The specified @var{archive} is always
426 created if it did not exist, when you request an update. But a warning is
427 issued unless you specify in advance that you expect to create it, by
428 using this modifier.
429
430 @item D
431 @cindex deterministic archives
432 @kindex --enable-deterministic-archives
433 Operate in @emph{deterministic} mode. When adding files and the archive
434 index use zero for UIDs, GIDs, timestamps, and use consistent file modes
435 for all files. When this option is used, if @command{ar} is used with
436 identical options and identical input files, multiple runs will create
437 identical output files regardless of the input files' owners, groups,
438 file modes, or modification times.
439
440 If @file{binutils} was configured with
441 @option{--enable-deterministic-archives}, then this mode is on by default.
442 It can be disabled with the @samp{U} modifier, below.
443
444 @item f
445 Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
446 names of any length. This will cause it to create archives which are
447 not compatible with the native @command{ar} program on some systems. If
448 this is a concern, the @samp{f} modifier may be used to truncate file
449 names when putting them in the archive.
450
451 @item i
452 Insert new files @emph{before} an existing member of the
453 archive. If you use the modifier @samp{i}, the name of an existing archive
454 member must be present as the @var{relpos} argument, before the
455 @var{archive} specification. (same as @samp{b}).
456
457 @item l
458 This modifier is accepted but not used.
459 @c whaffor ar l modifier??? presumably compat; with
460 @c what???---doc@@cygnus.com, 25jan91
461
462 @item N
463 Uses the @var{count} parameter. This is used if there are multiple
464 entries in the archive with the same name. Extract or delete instance
465 @var{count} of the given name from the archive.
466
467 @item o
468 @cindex dates in archive
469 Preserve the @emph{original} dates of members when extracting them. If
470 you do not specify this modifier, files extracted from the archive
471 are stamped with the time of extraction.
472
473 @item P
474 Use the full path name when matching names in the archive. @sc{gnu}
475 @command{ar} can not create an archive with a full path name (such archives
476 are not POSIX complaint), but other archive creators can. This option
477 will cause @sc{gnu} @command{ar} to match file names using a complete path
478 name, which can be convenient when extracting a single file from an
479 archive created by another tool.
480
481 @item s
482 @cindex writing archive index
483 Write an object-file index into the archive, or update an existing one,
484 even if no other change is made to the archive. You may use this modifier
485 flag either with any operation, or alone. Running @samp{ar s} on an
486 archive is equivalent to running @samp{ranlib} on it.
487
488 @item S
489 @cindex not writing archive index
490 Do not generate an archive symbol table. This can speed up building a
491 large library in several steps. The resulting archive can not be used
492 with the linker. In order to build a symbol table, you must omit the
493 @samp{S} modifier on the last execution of @samp{ar}, or you must run
494 @samp{ranlib} on the archive.
495
496 @item T
497 @cindex creating thin archive
498 Make the specified @var{archive} a @emph{thin} archive. If it already
499 exists and is a regular archive, the existing members must be present
500 in the same directory as @var{archive}.
501
502 @item u
503 @cindex updating an archive
504 Normally, @samp{ar r}@dots{} inserts all files
505 listed into the archive. If you would like to insert @emph{only} those
506 of the files you list that are newer than existing members of the same
507 names, use this modifier. The @samp{u} modifier is allowed only for the
508 operation @samp{r} (replace). In particular, the combination @samp{qu} is
509 not allowed, since checking the timestamps would lose any speed
510 advantage from the operation @samp{q}.
511
512 @item U
513 @cindex deterministic archives
514 @kindex --enable-deterministic-archives
515 Do @emph{not} operate in @emph{deterministic} mode. This is the inverse
516 of the @samp{D} modifier, above: added files and the archive index will
517 get their actual UID, GID, timestamp, and file mode values.
518
519 This is the default unless @file{binutils} was configured with
520 @option{--enable-deterministic-archives}.
521
522 @item v
523 This modifier requests the @emph{verbose} version of an operation. Many
524 operations display additional information, such as filenames processed,
525 when the modifier @samp{v} is appended.
526
527 @item V
528 This modifier shows the version number of @command{ar}.
529 @end table
530
531 @command{ar} ignores an initial option spelt @samp{-X32_64}, for
532 compatibility with AIX. The behaviour produced by this option is the
533 default for @sc{gnu} @command{ar}. @command{ar} does not support any of the other
534 @samp{-X} options; in particular, it does not support @option{-X32}
535 which is the default for AIX @command{ar}.
536
537 The optional command line switch @option{--plugin} @var{name} causes
538 @command{ar} to load the plugin called @var{name} which adds support
539 for more file formats. This option is only available if the toolchain
540 has been built with plugin support enabled.
541
542 The optional command line switch @option{--target} @var{bfdname}
543 specifies that the archive members are in an object code format
544 different from your system's default format. See
545 @xref{Target Selection}, for more information.
546
547 @c man end
548
549 @ignore
550 @c man begin SEEALSO ar
551 nm(1), ranlib(1), and the Info entries for @file{binutils}.
552 @c man end
553 @end ignore
554
555 @node ar scripts
556 @section Controlling @command{ar} with a Script
557
558 @smallexample
559 ar -M [ <@var{script} ]
560 @end smallexample
561
562 @cindex MRI compatibility, @command{ar}
563 @cindex scripts, @command{ar}
564 If you use the single command-line option @samp{-M} with @command{ar}, you
565 can control its operation with a rudimentary command language. This
566 form of @command{ar} operates interactively if standard input is coming
567 directly from a terminal. During interactive use, @command{ar} prompts for
568 input (the prompt is @samp{AR >}), and continues executing even after
569 errors. If you redirect standard input to a script file, no prompts are
570 issued, and @command{ar} abandons execution (with a nonzero exit code)
571 on any error.
572
573 The @command{ar} command language is @emph{not} designed to be equivalent
574 to the command-line options; in fact, it provides somewhat less control
575 over archives. The only purpose of the command language is to ease the
576 transition to @sc{gnu} @command{ar} for developers who already have scripts
577 written for the MRI ``librarian'' program.
578
579 The syntax for the @command{ar} command language is straightforward:
580 @itemize @bullet
581 @item
582 commands are recognized in upper or lower case; for example, @code{LIST}
583 is the same as @code{list}. In the following descriptions, commands are
584 shown in upper case for clarity.
585
586 @item
587 a single command may appear on each line; it is the first word on the
588 line.
589
590 @item
591 empty lines are allowed, and have no effect.
592
593 @item
594 comments are allowed; text after either of the characters @samp{*}
595 or @samp{;} is ignored.
596
597 @item
598 Whenever you use a list of names as part of the argument to an @command{ar}
599 command, you can separate the individual names with either commas or
600 blanks. Commas are shown in the explanations below, for clarity.
601
602 @item
603 @samp{+} is used as a line continuation character; if @samp{+} appears
604 at the end of a line, the text on the following line is considered part
605 of the current command.
606 @end itemize
607
608 Here are the commands you can use in @command{ar} scripts, or when using
609 @command{ar} interactively. Three of them have special significance:
610
611 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
612 a temporary file required for most of the other commands.
613
614 @code{SAVE} commits the changes so far specified by the script. Prior
615 to @code{SAVE}, commands affect only the temporary copy of the current
616 archive.
617
618 @table @code
619 @item ADDLIB @var{archive}
620 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
621 Add all the contents of @var{archive} (or, if specified, each named
622 @var{module} from @var{archive}) to the current archive.
623
624 Requires prior use of @code{OPEN} or @code{CREATE}.
625
626 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
627 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
628 @c else like "ar q..."
629 Add each named @var{member} as a module in the current archive.
630
631 Requires prior use of @code{OPEN} or @code{CREATE}.
632
633 @item CLEAR
634 Discard the contents of the current archive, canceling the effect of
635 any operations since the last @code{SAVE}. May be executed (with no
636 effect) even if no current archive is specified.
637
638 @item CREATE @var{archive}
639 Creates an archive, and makes it the current archive (required for many
640 other commands). The new archive is created with a temporary name; it
641 is not actually saved as @var{archive} until you use @code{SAVE}.
642 You can overwrite existing archives; similarly, the contents of any
643 existing file named @var{archive} will not be destroyed until @code{SAVE}.
644
645 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
646 Delete each listed @var{module} from the current archive; equivalent to
647 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
648
649 Requires prior use of @code{OPEN} or @code{CREATE}.
650
651 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
652 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
653 List each named @var{module} present in @var{archive}. The separate
654 command @code{VERBOSE} specifies the form of the output: when verbose
655 output is off, output is like that of @samp{ar -t @var{archive}
656 @var{module}@dots{}}. When verbose output is on, the listing is like
657 @samp{ar -tv @var{archive} @var{module}@dots{}}.
658
659 Output normally goes to the standard output stream; however, if you
660 specify @var{outputfile} as a final argument, @command{ar} directs the
661 output to that file.
662
663 @item END
664 Exit from @command{ar}, with a @code{0} exit code to indicate successful
665 completion. This command does not save the output file; if you have
666 changed the current archive since the last @code{SAVE} command, those
667 changes are lost.
668
669 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
670 Extract each named @var{module} from the current archive, writing them
671 into the current directory as separate files. Equivalent to @samp{ar -x
672 @var{archive} @var{module}@dots{}}.
673
674 Requires prior use of @code{OPEN} or @code{CREATE}.
675
676 @ignore
677 @c FIXME Tokens but no commands???
678 @item FULLDIR
679
680 @item HELP
681 @end ignore
682
683 @item LIST
684 Display full contents of the current archive, in ``verbose'' style
685 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
686 tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
687 enhancement, rather than present for MRI compatibility.)
688
689 Requires prior use of @code{OPEN} or @code{CREATE}.
690
691 @item OPEN @var{archive}
692 Opens an existing archive for use as the current archive (required for
693 many other commands). Any changes as the result of subsequent commands
694 will not actually affect @var{archive} until you next use @code{SAVE}.
695
696 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
697 In the current archive, replace each existing @var{module} (named in
698 the @code{REPLACE} arguments) from files in the current working directory.
699 To execute this command without errors, both the file, and the module in
700 the current archive, must exist.
701
702 Requires prior use of @code{OPEN} or @code{CREATE}.
703
704 @item VERBOSE
705 Toggle an internal flag governing the output from @code{DIRECTORY}.
706 When the flag is on, @code{DIRECTORY} output matches output from
707 @samp{ar -tv }@dots{}.
708
709 @item SAVE
710 Commit your changes to the current archive, and actually save it as a
711 file with the name specified in the last @code{CREATE} or @code{OPEN}
712 command.
713
714 Requires prior use of @code{OPEN} or @code{CREATE}.
715
716 @end table
717
718 @iftex
719 @node ld
720 @chapter ld
721 @cindex linker
722 @kindex ld
723 The @sc{gnu} linker @command{ld} is now described in a separate manual.
724 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
725 @end iftex
726
727 @node nm
728 @chapter nm
729 @cindex symbols
730 @kindex nm
731
732 @c man title nm list symbols from object files
733
734 @smallexample
735 @c man begin SYNOPSIS nm
736 nm [@option{-A}|@option{-o}|@option{--print-file-name}] [@option{-a}|@option{--debug-syms}]
737 [@option{-B}|@option{--format=bsd}] [@option{-C}|@option{--demangle}[=@var{style}]]
738 [@option{-D}|@option{--dynamic}] [@option{-f}@var{format}|@option{--format=}@var{format}]
739 [@option{-g}|@option{--extern-only}] [@option{-h}|@option{--help}]
740 [@option{-l}|@option{--line-numbers}] [@option{-n}|@option{-v}|@option{--numeric-sort}]
741 [@option{-P}|@option{--portability}] [@option{-p}|@option{--no-sort}]
742 [@option{-r}|@option{--reverse-sort}] [@option{-S}|@option{--print-size}]
743 [@option{-s}|@option{--print-armap}] [@option{-t} @var{radix}|@option{--radix=}@var{radix}]
744 [@option{-u}|@option{--undefined-only}] [@option{-V}|@option{--version}]
745 [@option{-X 32_64}] [@option{--defined-only}] [@option{--no-demangle}]
746 [@option{--plugin} @var{name}] [@option{--size-sort}] [@option{--special-syms}]
747 [@option{--synthetic}] [@option{--target=}@var{bfdname}]
748 [@var{objfile}@dots{}]
749 @c man end
750 @end smallexample
751
752 @c man begin DESCRIPTION nm
753 @sc{gnu} @command{nm} lists the symbols from object files @var{objfile}@dots{}.
754 If no object files are listed as arguments, @command{nm} assumes the file
755 @file{a.out}.
756
757 For each symbol, @command{nm} shows:
758
759 @itemize @bullet
760 @item
761 The symbol value, in the radix selected by options (see below), or
762 hexadecimal by default.
763
764 @item
765 The symbol type. At least the following types are used; others are, as
766 well, depending on the object file format. If lowercase, the symbol is
767 usually local; if uppercase, the symbol is global (external). There
768 are however a few lowercase symbols that are shown for special global
769 symbols (@code{u}, @code{v} and @code{w}).
770
771 @c Some more detail on exactly what these symbol types are used for
772 @c would be nice.
773 @table @code
774 @item A
775 The symbol's value is absolute, and will not be changed by further
776 linking.
777
778 @item B
779 @itemx b
780 The symbol is in the uninitialized data section (known as BSS).
781
782 @item C
783 The symbol is common. Common symbols are uninitialized data. When
784 linking, multiple common symbols may appear with the same name. If the
785 symbol is defined anywhere, the common symbols are treated as undefined
786 references.
787 @ifclear man
788 For more details on common symbols, see the discussion of
789 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
790 @end ifclear
791
792 @item D
793 @itemx d
794 The symbol is in the initialized data section.
795
796 @item G
797 @itemx g
798 The symbol is in an initialized data section for small objects. Some
799 object file formats permit more efficient access to small data objects,
800 such as a global int variable as opposed to a large global array.
801
802 @item i
803 For PE format files this indicates that the symbol is in a section
804 specific to the implementation of DLLs. For ELF format files this
805 indicates that the symbol is an indirect function. This is a GNU
806 extension to the standard set of ELF symbol types. It indicates a
807 symbol which if referenced by a relocation does not evaluate to its
808 address, but instead must be invoked at runtime. The runtime
809 execution will then return the value to be used in the relocation.
810
811 @item I
812 The symbol is an indirect reference to another symbol.
813
814 @item N
815 The symbol is a debugging symbol.
816
817 @item p
818 The symbols is in a stack unwind section.
819
820 @item R
821 @itemx r
822 The symbol is in a read only data section.
823
824 @item S
825 @itemx s
826 The symbol is in an uninitialized data section for small objects.
827
828 @item T
829 @itemx t
830 The symbol is in the text (code) section.
831
832 @item U
833 The symbol is undefined.
834
835 @item u
836 The symbol is a unique global symbol. This is a GNU extension to the
837 standard set of ELF symbol bindings. For such a symbol the dynamic linker
838 will make sure that in the entire process there is just one symbol with
839 this name and type in use.
840
841 @item V
842 @itemx v
843 The symbol is a weak object. When a weak defined symbol is linked with
844 a normal defined symbol, the normal defined symbol is used with no error.
845 When a weak undefined symbol is linked and the symbol is not defined,
846 the value of the weak symbol becomes zero with no error. On some
847 systems, uppercase indicates that a default value has been specified.
848
849 @item W
850 @itemx w
851 The symbol is a weak symbol that has not been specifically tagged as a
852 weak object symbol. When a weak defined symbol is linked with a normal
853 defined symbol, the normal defined symbol is used with no error.
854 When a weak undefined symbol is linked and the symbol is not defined,
855 the value of the symbol is determined in a system-specific manner without
856 error. On some systems, uppercase indicates that a default value has been
857 specified.
858
859 @item -
860 The symbol is a stabs symbol in an a.out object file. In this case, the
861 next values printed are the stabs other field, the stabs desc field, and
862 the stab type. Stabs symbols are used to hold debugging information.
863
864 @item ?
865 The symbol type is unknown, or object file format specific.
866 @end table
867
868 @item
869 The symbol name.
870 @end itemize
871
872 @c man end
873
874 @c man begin OPTIONS nm
875 The long and short forms of options, shown here as alternatives, are
876 equivalent.
877
878 @table @env
879 @item -A
880 @itemx -o
881 @itemx --print-file-name
882 @cindex input file name
883 @cindex file name
884 @cindex source file name
885 Precede each symbol by the name of the input file (or archive member)
886 in which it was found, rather than identifying the input file once only,
887 before all of its symbols.
888
889 @item -a
890 @itemx --debug-syms
891 @cindex debugging symbols
892 Display all symbols, even debugger-only symbols; normally these are not
893 listed.
894
895 @item -B
896 @cindex @command{nm} format
897 @cindex @command{nm} compatibility
898 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
899
900 @item -C
901 @itemx --demangle[=@var{style}]
902 @cindex demangling in nm
903 Decode (@dfn{demangle}) low-level symbol names into user-level names.
904 Besides removing any initial underscore prepended by the system, this
905 makes C++ function names readable. Different compilers have different
906 mangling styles. The optional demangling style argument can be used to
907 choose an appropriate demangling style for your compiler. @xref{c++filt},
908 for more information on demangling.
909
910 @item --no-demangle
911 Do not demangle low-level symbol names. This is the default.
912
913 @item -D
914 @itemx --dynamic
915 @cindex dynamic symbols
916 Display the dynamic symbols rather than the normal symbols. This is
917 only meaningful for dynamic objects, such as certain types of shared
918 libraries.
919
920 @item -f @var{format}
921 @itemx --format=@var{format}
922 @cindex @command{nm} format
923 @cindex @command{nm} compatibility
924 Use the output format @var{format}, which can be @code{bsd},
925 @code{sysv}, or @code{posix}. The default is @code{bsd}.
926 Only the first character of @var{format} is significant; it can be
927 either upper or lower case.
928
929 @item -g
930 @itemx --extern-only
931 @cindex external symbols
932 Display only external symbols.
933
934 @item -h
935 @itemx --help
936 Show a summary of the options to @command{nm} and exit.
937
938 @item -l
939 @itemx --line-numbers
940 @cindex symbol line numbers
941 For each symbol, use debugging information to try to find a filename and
942 line number. For a defined symbol, look for the line number of the
943 address of the symbol. For an undefined symbol, look for the line
944 number of a relocation entry which refers to the symbol. If line number
945 information can be found, print it after the other symbol information.
946
947 @item -n
948 @itemx -v
949 @itemx --numeric-sort
950 Sort symbols numerically by their addresses, rather than alphabetically
951 by their names.
952
953 @item -p
954 @itemx --no-sort
955 @cindex sorting symbols
956 Do not bother to sort the symbols in any order; print them in the order
957 encountered.
958
959 @item -P
960 @itemx --portability
961 Use the POSIX.2 standard output format instead of the default format.
962 Equivalent to @samp{-f posix}.
963
964 @item -r
965 @itemx --reverse-sort
966 Reverse the order of the sort (whether numeric or alphabetic); let the
967 last come first.
968
969 @item -S
970 @itemx --print-size
971 Print both value and size of defined symbols for the @code{bsd} output style.
972 This option has no effect for object formats that do not record symbol
973 sizes, unless @samp{--size-sort} is also used in which case a
974 calculated size is displayed.
975
976 @item -s
977 @itemx --print-armap
978 @cindex symbol index, listing
979 When listing symbols from archive members, include the index: a mapping
980 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
981 contain definitions for which names.
982
983 @item -t @var{radix}
984 @itemx --radix=@var{radix}
985 Use @var{radix} as the radix for printing the symbol values. It must be
986 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
987
988 @item -u
989 @itemx --undefined-only
990 @cindex external symbols
991 @cindex undefined symbols
992 Display only undefined symbols (those external to each object file).
993
994 @item -V
995 @itemx --version
996 Show the version number of @command{nm} and exit.
997
998 @item -X
999 This option is ignored for compatibility with the AIX version of
1000 @command{nm}. It takes one parameter which must be the string
1001 @option{32_64}. The default mode of AIX @command{nm} corresponds
1002 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
1003
1004 @item --defined-only
1005 @cindex external symbols
1006 @cindex undefined symbols
1007 Display only defined symbols for each object file.
1008
1009 @item --plugin @var{name}
1010 @cindex load plugin
1011 Load the plugin called @var{name} to add support for extra target
1012 types. This option is only available if the toolchain has been built
1013 with plugin support enabled.
1014
1015 @item --size-sort
1016 Sort symbols by size. The size is computed as the difference between
1017 the value of the symbol and the value of the symbol with the next higher
1018 value. If the @code{bsd} output format is used the size of the symbol
1019 is printed, rather than the value, and @samp{-S} must be used in order
1020 both size and value to be printed.
1021
1022 @item --special-syms
1023 Display symbols which have a target-specific special meaning. These
1024 symbols are usually used by the target for some special processing and
1025 are not normally helpful when included in the normal symbol lists.
1026 For example for ARM targets this option would skip the mapping symbols
1027 used to mark transitions between ARM code, THUMB code and data.
1028
1029 @item --synthetic
1030 Include synthetic symbols in the output. These are special symbols
1031 created by the linker for various purposes. They are not shown by
1032 default since they are not part of the binary's original source code.
1033
1034 @item --target=@var{bfdname}
1035 @cindex object code format
1036 Specify an object code format other than your system's default format.
1037 @xref{Target Selection}, for more information.
1038
1039 @end table
1040
1041 @c man end
1042
1043 @ignore
1044 @c man begin SEEALSO nm
1045 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
1046 @c man end
1047 @end ignore
1048
1049 @node objcopy
1050 @chapter objcopy
1051
1052 @c man title objcopy copy and translate object files
1053
1054 @smallexample
1055 @c man begin SYNOPSIS objcopy
1056 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
1057 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
1058 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
1059 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
1060 [@option{-S}|@option{--strip-all}]
1061 [@option{-g}|@option{--strip-debug}]
1062 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
1063 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
1064 [@option{--strip-unneeded-symbol=}@var{symbolname}]
1065 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
1066 [@option{--localize-hidden}]
1067 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
1068 [@option{--globalize-symbol=}@var{symbolname}]
1069 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
1070 [@option{-w}|@option{--wildcard}]
1071 [@option{-x}|@option{--discard-all}]
1072 [@option{-X}|@option{--discard-locals}]
1073 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
1074 [@option{-i} [@var{breadth}]|@option{--interleave}[=@var{breadth}]]
1075 [@option{--interleave-width=}@var{width}]
1076 [@option{-j} @var{sectionpattern}|@option{--only-section=}@var{sectionpattern}]
1077 [@option{-R} @var{sectionpattern}|@option{--remove-section=}@var{sectionpattern}]
1078 [@option{-p}|@option{--preserve-dates}]
1079 [@option{-D}|@option{--enable-deterministic-archives}]
1080 [@option{-U}|@option{--disable-deterministic-archives}]
1081 [@option{--debugging}]
1082 [@option{--gap-fill=}@var{val}]
1083 [@option{--pad-to=}@var{address}]
1084 [@option{--set-start=}@var{val}]
1085 [@option{--adjust-start=}@var{incr}]
1086 [@option{--change-addresses=}@var{incr}]
1087 [@option{--change-section-address} @var{sectionpattern}@{=,+,-@}@var{val}]
1088 [@option{--change-section-lma} @var{sectionpattern}@{=,+,-@}@var{val}]
1089 [@option{--change-section-vma} @var{sectionpattern}@{=,+,-@}@var{val}]
1090 [@option{--change-warnings}] [@option{--no-change-warnings}]
1091 [@option{--set-section-flags} @var{sectionpattern}=@var{flags}]
1092 [@option{--add-section} @var{sectionname}=@var{filename}]
1093 [@option{--dump-section} @var{sectionname}=@var{filename}]
1094 [@option{--update-section} @var{sectionname}=@var{filename}]
1095 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
1096 [@option{--long-section-names} @{enable,disable,keep@}]
1097 [@option{--change-leading-char}] [@option{--remove-leading-char}]
1098 [@option{--reverse-bytes=}@var{num}]
1099 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
1100 [@option{--redefine-sym} @var{old}=@var{new}]
1101 [@option{--redefine-syms=}@var{filename}]
1102 [@option{--weaken}]
1103 [@option{--keep-symbols=}@var{filename}]
1104 [@option{--strip-symbols=}@var{filename}]
1105 [@option{--strip-unneeded-symbols=}@var{filename}]
1106 [@option{--keep-global-symbols=}@var{filename}]
1107 [@option{--localize-symbols=}@var{filename}]
1108 [@option{--globalize-symbols=}@var{filename}]
1109 [@option{--weaken-symbols=}@var{filename}]
1110 [@option{--alt-machine-code=}@var{index}]
1111 [@option{--prefix-symbols=}@var{string}]
1112 [@option{--prefix-sections=}@var{string}]
1113 [@option{--prefix-alloc-sections=}@var{string}]
1114 [@option{--add-gnu-debuglink=}@var{path-to-file}]
1115 [@option{--keep-file-symbols}]
1116 [@option{--only-keep-debug}]
1117 [@option{--strip-dwo}]
1118 [@option{--extract-dwo}]
1119 [@option{--extract-symbol}]
1120 [@option{--writable-text}]
1121 [@option{--readonly-text}]
1122 [@option{--pure}]
1123 [@option{--impure}]
1124 [@option{--file-alignment=}@var{num}]
1125 [@option{--heap=}@var{size}]
1126 [@option{--image-base=}@var{address}]
1127 [@option{--section-alignment=}@var{num}]
1128 [@option{--stack=}@var{size}]
1129 [@option{--subsystem=}@var{which}:@var{major}.@var{minor}]
1130 [@option{--compress-debug-sections}]
1131 [@option{--decompress-debug-sections}]
1132 [@option{--dwarf-depth=@var{n}}]
1133 [@option{--dwarf-start=@var{n}}]
1134 [@option{-v}|@option{--verbose}]
1135 [@option{-V}|@option{--version}]
1136 [@option{--help}] [@option{--info}]
1137 @var{infile} [@var{outfile}]
1138 @c man end
1139 @end smallexample
1140
1141 @c man begin DESCRIPTION objcopy
1142 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1143 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1144 read and write the object files. It can write the destination object
1145 file in a format different from that of the source object file. The
1146 exact behavior of @command{objcopy} is controlled by command-line options.
1147 Note that @command{objcopy} should be able to copy a fully linked file
1148 between any two formats. However, copying a relocatable object file
1149 between any two formats may not work as expected.
1150
1151 @command{objcopy} creates temporary files to do its translations and
1152 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1153 translation work; it has access to all the formats described in @sc{bfd}
1154 and thus is able to recognize most formats without being told
1155 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1156
1157 @command{objcopy} can be used to generate S-records by using an output
1158 target of @samp{srec} (e.g., use @samp{-O srec}).
1159
1160 @command{objcopy} can be used to generate a raw binary file by using an
1161 output target of @samp{binary} (e.g., use @option{-O binary}). When
1162 @command{objcopy} generates a raw binary file, it will essentially produce
1163 a memory dump of the contents of the input object file. All symbols and
1164 relocation information will be discarded. The memory dump will start at
1165 the load address of the lowest section copied into the output file.
1166
1167 When generating an S-record or a raw binary file, it may be helpful to
1168 use @option{-S} to remove sections containing debugging information. In
1169 some cases @option{-R} will be useful to remove sections which contain
1170 information that is not needed by the binary file.
1171
1172 Note---@command{objcopy} is not able to change the endianness of its input
1173 files. If the input format has an endianness (some formats do not),
1174 @command{objcopy} can only copy the inputs into file formats that have the
1175 same endianness or which have no endianness (e.g., @samp{srec}).
1176 (However, see the @option{--reverse-bytes} option.)
1177
1178 @c man end
1179
1180 @c man begin OPTIONS objcopy
1181
1182 @table @env
1183 @item @var{infile}
1184 @itemx @var{outfile}
1185 The input and output files, respectively.
1186 If you do not specify @var{outfile}, @command{objcopy} creates a
1187 temporary file and destructively renames the result with
1188 the name of @var{infile}.
1189
1190 @item -I @var{bfdname}
1191 @itemx --input-target=@var{bfdname}
1192 Consider the source file's object format to be @var{bfdname}, rather than
1193 attempting to deduce it. @xref{Target Selection}, for more information.
1194
1195 @item -O @var{bfdname}
1196 @itemx --output-target=@var{bfdname}
1197 Write the output file using the object format @var{bfdname}.
1198 @xref{Target Selection}, for more information.
1199
1200 @item -F @var{bfdname}
1201 @itemx --target=@var{bfdname}
1202 Use @var{bfdname} as the object format for both the input and the output
1203 file; i.e., simply transfer data from source to destination with no
1204 translation. @xref{Target Selection}, for more information.
1205
1206 @item -B @var{bfdarch}
1207 @itemx --binary-architecture=@var{bfdarch}
1208 Useful when transforming a architecture-less input file into an object file.
1209 In this case the output architecture can be set to @var{bfdarch}. This
1210 option will be ignored if the input file has a known @var{bfdarch}. You
1211 can access this binary data inside a program by referencing the special
1212 symbols that are created by the conversion process. These symbols are
1213 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1214 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1215 an object file and then access it in your code using these symbols.
1216
1217 @item -j @var{sectionpattern}
1218 @itemx --only-section=@var{sectionpattern}
1219 Copy only the indicated sections from the input file to the output file.
1220 This option may be given more than once. Note that using this option
1221 inappropriately may make the output file unusable. Wildcard
1222 characters are accepted in @var{sectionpattern}.
1223
1224 @item -R @var{sectionpattern}
1225 @itemx --remove-section=@var{sectionpattern}
1226 Remove any section matching @var{sectionpattern} from the output file.
1227 This option may be given more than once. Note that using this option
1228 inappropriately may make the output file unusable. Wildcard
1229 characters are accepted in @var{sectionpattern}. Using both the
1230 @option{-j} and @option{-R} options together results in undefined
1231 behaviour.
1232
1233 @item -S
1234 @itemx --strip-all
1235 Do not copy relocation and symbol information from the source file.
1236
1237 @item -g
1238 @itemx --strip-debug
1239 Do not copy debugging symbols or sections from the source file.
1240
1241 @item --strip-unneeded
1242 Strip all symbols that are not needed for relocation processing.
1243
1244 @item -K @var{symbolname}
1245 @itemx --keep-symbol=@var{symbolname}
1246 When stripping symbols, keep symbol @var{symbolname} even if it would
1247 normally be stripped. This option may be given more than once.
1248
1249 @item -N @var{symbolname}
1250 @itemx --strip-symbol=@var{symbolname}
1251 Do not copy symbol @var{symbolname} from the source file. This option
1252 may be given more than once.
1253
1254 @item --strip-unneeded-symbol=@var{symbolname}
1255 Do not copy symbol @var{symbolname} from the source file unless it is needed
1256 by a relocation. This option may be given more than once.
1257
1258 @item -G @var{symbolname}
1259 @itemx --keep-global-symbol=@var{symbolname}
1260 Keep only symbol @var{symbolname} global. Make all other symbols local
1261 to the file, so that they are not visible externally. This option may
1262 be given more than once.
1263
1264 @item --localize-hidden
1265 In an ELF object, mark all symbols that have hidden or internal visibility
1266 as local. This option applies on top of symbol-specific localization options
1267 such as @option{-L}.
1268
1269 @item -L @var{symbolname}
1270 @itemx --localize-symbol=@var{symbolname}
1271 Make symbol @var{symbolname} local to the file, so that it is not
1272 visible externally. This option may be given more than once.
1273
1274 @item -W @var{symbolname}
1275 @itemx --weaken-symbol=@var{symbolname}
1276 Make symbol @var{symbolname} weak. This option may be given more than once.
1277
1278 @item --globalize-symbol=@var{symbolname}
1279 Give symbol @var{symbolname} global scoping so that it is visible
1280 outside of the file in which it is defined. This option may be given
1281 more than once.
1282
1283 @item -w
1284 @itemx --wildcard
1285 Permit regular expressions in @var{symbolname}s used in other command
1286 line options. The question mark (?), asterisk (*), backslash (\) and
1287 square brackets ([]) operators can be used anywhere in the symbol
1288 name. If the first character of the symbol name is the exclamation
1289 point (!) then the sense of the switch is reversed for that symbol.
1290 For example:
1291
1292 @smallexample
1293 -w -W !foo -W fo*
1294 @end smallexample
1295
1296 would cause objcopy to weaken all symbols that start with ``fo''
1297 except for the symbol ``foo''.
1298
1299 @item -x
1300 @itemx --discard-all
1301 Do not copy non-global symbols from the source file.
1302 @c FIXME any reason to prefer "non-global" to "local" here?
1303
1304 @item -X
1305 @itemx --discard-locals
1306 Do not copy compiler-generated local symbols.
1307 (These usually start with @samp{L} or @samp{.}.)
1308
1309 @item -b @var{byte}
1310 @itemx --byte=@var{byte}
1311 If interleaving has been enabled via the @option{--interleave} option
1312 then start the range of bytes to keep at the @var{byte}th byte.
1313 @var{byte} can be in the range from 0 to @var{breadth}-1, where
1314 @var{breadth} is the value given by the @option{--interleave} option.
1315
1316 @item -i [@var{breadth}]
1317 @itemx --interleave[=@var{breadth}]
1318 Only copy a range out of every @var{breadth} bytes. (Header data is
1319 not affected). Select which byte in the range begins the copy with
1320 the @option{--byte} option. Select the width of the range with the
1321 @option{--interleave-width} option.
1322
1323 This option is useful for creating files to program @sc{rom}. It is
1324 typically used with an @code{srec} output target. Note that
1325 @command{objcopy} will complain if you do not specify the
1326 @option{--byte} option as well.
1327
1328 The default interleave breadth is 4, so with @option{--byte} set to 0,
1329 @command{objcopy} would copy the first byte out of every four bytes
1330 from the input to the output.
1331
1332 @item --interleave-width=@var{width}
1333 When used with the @option{--interleave} option, copy @var{width}
1334 bytes at a time. The start of the range of bytes to be copied is set
1335 by the @option{--byte} option, and the extent of the range is set with
1336 the @option{--interleave} option.
1337
1338 The default value for this option is 1. The value of @var{width} plus
1339 the @var{byte} value set by the @option{--byte} option must not exceed
1340 the interleave breadth set by the @option{--interleave} option.
1341
1342 This option can be used to create images for two 16-bit flashes interleaved
1343 in a 32-bit bus by passing @option{-b 0 -i 4 --interleave-width=2}
1344 and @option{-b 2 -i 4 --interleave-width=2} to two @command{objcopy}
1345 commands. If the input was '12345678' then the outputs would be
1346 '1256' and '3478' respectively.
1347
1348 @item -p
1349 @itemx --preserve-dates
1350 Set the access and modification dates of the output file to be the same
1351 as those of the input file.
1352
1353 @item -D
1354 @itemx --enable-deterministic-archives
1355 @cindex deterministic archives
1356 @kindex --enable-deterministic-archives
1357 Operate in @emph{deterministic} mode. When copying archive members
1358 and writing the archive index, use zero for UIDs, GIDs, timestamps,
1359 and use consistent file modes for all files.
1360
1361 If @file{binutils} was configured with
1362 @option{--enable-deterministic-archives}, then this mode is on by default.
1363 It can be disabled with the @samp{-U} option, below.
1364
1365 @item -U
1366 @itemx --disable-deterministic-archives
1367 @cindex deterministic archives
1368 @kindex --enable-deterministic-archives
1369 Do @emph{not} operate in @emph{deterministic} mode. This is the
1370 inverse of the @option{-D} option, above: when copying archive members
1371 and writing the archive index, use their actual UID, GID, timestamp,
1372 and file mode values.
1373
1374 This is the default unless @file{binutils} was configured with
1375 @option{--enable-deterministic-archives}.
1376
1377 @item --debugging
1378 Convert debugging information, if possible. This is not the default
1379 because only certain debugging formats are supported, and the
1380 conversion process can be time consuming.
1381
1382 @item --gap-fill @var{val}
1383 Fill gaps between sections with @var{val}. This operation applies to
1384 the @emph{load address} (LMA) of the sections. It is done by increasing
1385 the size of the section with the lower address, and filling in the extra
1386 space created with @var{val}.
1387
1388 @item --pad-to @var{address}
1389 Pad the output file up to the load address @var{address}. This is
1390 done by increasing the size of the last section. The extra space is
1391 filled in with the value specified by @option{--gap-fill} (default zero).
1392
1393 @item --set-start @var{val}
1394 Set the start address of the new file to @var{val}. Not all object file
1395 formats support setting the start address.
1396
1397 @item --change-start @var{incr}
1398 @itemx --adjust-start @var{incr}
1399 @cindex changing start address
1400 Change the start address by adding @var{incr}. Not all object file
1401 formats support setting the start address.
1402
1403 @item --change-addresses @var{incr}
1404 @itemx --adjust-vma @var{incr}
1405 @cindex changing object addresses
1406 Change the VMA and LMA addresses of all sections, as well as the start
1407 address, by adding @var{incr}. Some object file formats do not permit
1408 section addresses to be changed arbitrarily. Note that this does not
1409 relocate the sections; if the program expects sections to be loaded at a
1410 certain address, and this option is used to change the sections such
1411 that they are loaded at a different address, the program may fail.
1412
1413 @item --change-section-address @var{sectionpattern}@{=,+,-@}@var{val}
1414 @itemx --adjust-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1415 @cindex changing section address
1416 Set or change both the VMA address and the LMA address of any section
1417 matching @var{sectionpattern}. If @samp{=} is used, the section
1418 address is set to @var{val}. Otherwise, @var{val} is added to or
1419 subtracted from the section address. See the comments under
1420 @option{--change-addresses}, above. If @var{sectionpattern} does not
1421 match any sections in the input file, a warning will be issued, unless
1422 @option{--no-change-warnings} is used.
1423
1424 @item --change-section-lma @var{sectionpattern}@{=,+,-@}@var{val}
1425 @cindex changing section LMA
1426 Set or change the LMA address of any sections matching
1427 @var{sectionpattern}. The LMA address is the address where the
1428 section will be loaded into memory at program load time. Normally
1429 this is the same as the VMA address, which is the address of the
1430 section at program run time, but on some systems, especially those
1431 where a program is held in ROM, the two can be different. If @samp{=}
1432 is used, the section address is set to @var{val}. Otherwise,
1433 @var{val} is added to or subtracted from the section address. See the
1434 comments under @option{--change-addresses}, above. If
1435 @var{sectionpattern} does not match any sections in the input file, a
1436 warning will be issued, unless @option{--no-change-warnings} is used.
1437
1438 @item --change-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1439 @cindex changing section VMA
1440 Set or change the VMA address of any section matching
1441 @var{sectionpattern}. The VMA address is the address where the
1442 section will be located once the program has started executing.
1443 Normally this is the same as the LMA address, which is the address
1444 where the section will be loaded into memory, but on some systems,
1445 especially those where a program is held in ROM, the two can be
1446 different. If @samp{=} is used, the section address is set to
1447 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1448 section address. See the comments under @option{--change-addresses},
1449 above. If @var{sectionpattern} does not match any sections in the
1450 input file, a warning will be issued, unless
1451 @option{--no-change-warnings} is used.
1452
1453 @item --change-warnings
1454 @itemx --adjust-warnings
1455 If @option{--change-section-address} or @option{--change-section-lma} or
1456 @option{--change-section-vma} is used, and the section pattern does not
1457 match any sections, issue a warning. This is the default.
1458
1459 @item --no-change-warnings
1460 @itemx --no-adjust-warnings
1461 Do not issue a warning if @option{--change-section-address} or
1462 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1463 if the section pattern does not match any sections.
1464
1465 @item --set-section-flags @var{sectionpattern}=@var{flags}
1466 Set the flags for any sections matching @var{sectionpattern}. The
1467 @var{flags} argument is a comma separated string of flag names. The
1468 recognized names are @samp{alloc}, @samp{contents}, @samp{load},
1469 @samp{noload}, @samp{readonly}, @samp{code}, @samp{data}, @samp{rom},
1470 @samp{share}, and @samp{debug}. You can set the @samp{contents} flag
1471 for a section which does not have contents, but it is not meaningful
1472 to clear the @samp{contents} flag of a section which does have
1473 contents--just remove the section instead. Not all flags are
1474 meaningful for all object file formats.
1475
1476 @item --add-section @var{sectionname}=@var{filename}
1477 Add a new section named @var{sectionname} while copying the file. The
1478 contents of the new section are taken from the file @var{filename}. The
1479 size of the section will be the size of the file. This option only
1480 works on file formats which can support sections with arbitrary names.
1481 Note - it may be necessary to use the @option{--set-section-flags}
1482 option to set the attributes of the newly created section.
1483
1484 @item --dump-section @var{sectionname}=@var{filename}
1485 Place the contents of section named @var{sectionname} into the file
1486 @var{filename}, overwriting any contents that may have been there
1487 previously. This option is the inverse of @option{--add-section}.
1488 This option is similar to the @option{--only-section} option except
1489 that it does not create a formatted file, it just dumps the contents
1490 as raw binary data, without applying any relocations. The option can
1491 be specified more than once.
1492
1493 @item --update-section @var{sectionname}=@var{filename}
1494 Replace the existing contents of a section named @var{sectionname}
1495 with the contents of file @var{filename}. The size of the section
1496 will be adjusted to the size of the file. The section flags for
1497 @var{sectionname} will be unchanged. For ELF format files the section
1498 to segment mapping will also remain unchanged, something which is not
1499 possible using @option{--remove-section} followed by
1500 @option{--add-section}. The option can be specified more than once.
1501
1502 Note - it is possible to use @option{--rename-section} and
1503 @option{--update-section} to both update and rename a section from one
1504 command line. In this case, pass the original section name to
1505 @option{--update-section}, and the original and new section names to
1506 @option{--rename-section}.
1507
1508 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1509 Rename a section from @var{oldname} to @var{newname}, optionally
1510 changing the section's flags to @var{flags} in the process. This has
1511 the advantage over usng a linker script to perform the rename in that
1512 the output stays as an object file and does not become a linked
1513 executable.
1514
1515 This option is particularly helpful when the input format is binary,
1516 since this will always create a section called .data. If for example,
1517 you wanted instead to create a section called .rodata containing binary
1518 data you could use the following command line to achieve it:
1519
1520 @smallexample
1521 objcopy -I binary -O <output_format> -B <architecture> \
1522 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1523 <input_binary_file> <output_object_file>
1524 @end smallexample
1525
1526 @item --long-section-names @{enable,disable,keep@}
1527 Controls the handling of long section names when processing @code{COFF}
1528 and @code{PE-COFF} object formats. The default behaviour, @samp{keep},
1529 is to preserve long section names if any are present in the input file.
1530 The @samp{enable} and @samp{disable} options forcibly enable or disable
1531 the use of long section names in the output object; when @samp{disable}
1532 is in effect, any long section names in the input object will be truncated.
1533 The @samp{enable} option will only emit long section names if any are
1534 present in the inputs; this is mostly the same as @samp{keep}, but it
1535 is left undefined whether the @samp{enable} option might force the
1536 creation of an empty string table in the output file.
1537
1538 @item --change-leading-char
1539 Some object file formats use special characters at the start of
1540 symbols. The most common such character is underscore, which compilers
1541 often add before every symbol. This option tells @command{objcopy} to
1542 change the leading character of every symbol when it converts between
1543 object file formats. If the object file formats use the same leading
1544 character, this option has no effect. Otherwise, it will add a
1545 character, or remove a character, or change a character, as
1546 appropriate.
1547
1548 @item --remove-leading-char
1549 If the first character of a global symbol is a special symbol leading
1550 character used by the object file format, remove the character. The
1551 most common symbol leading character is underscore. This option will
1552 remove a leading underscore from all global symbols. This can be useful
1553 if you want to link together objects of different file formats with
1554 different conventions for symbol names. This is different from
1555 @option{--change-leading-char} because it always changes the symbol name
1556 when appropriate, regardless of the object file format of the output
1557 file.
1558
1559 @item --reverse-bytes=@var{num}
1560 Reverse the bytes in a section with output contents. A section length must
1561 be evenly divisible by the value given in order for the swap to be able to
1562 take place. Reversing takes place before the interleaving is performed.
1563
1564 This option is used typically in generating ROM images for problematic
1565 target systems. For example, on some target boards, the 32-bit words
1566 fetched from 8-bit ROMs are re-assembled in little-endian byte order
1567 regardless of the CPU byte order. Depending on the programming model, the
1568 endianness of the ROM may need to be modified.
1569
1570 Consider a simple file with a section containing the following eight
1571 bytes: @code{12345678}.
1572
1573 Using @samp{--reverse-bytes=2} for the above example, the bytes in the
1574 output file would be ordered @code{21436587}.
1575
1576 Using @samp{--reverse-bytes=4} for the above example, the bytes in the
1577 output file would be ordered @code{43218765}.
1578
1579 By using @samp{--reverse-bytes=2} for the above example, followed by
1580 @samp{--reverse-bytes=4} on the output file, the bytes in the second
1581 output file would be ordered @code{34127856}.
1582
1583 @item --srec-len=@var{ival}
1584 Meaningful only for srec output. Set the maximum length of the Srecords
1585 being produced to @var{ival}. This length covers both address, data and
1586 crc fields.
1587
1588 @item --srec-forceS3
1589 Meaningful only for srec output. Avoid generation of S1/S2 records,
1590 creating S3-only record format.
1591
1592 @item --redefine-sym @var{old}=@var{new}
1593 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1594 when one is trying link two things together for which you have no
1595 source, and there are name collisions.
1596
1597 @item --redefine-syms=@var{filename}
1598 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1599 listed in the file @var{filename}. @var{filename} is simply a flat file,
1600 with one symbol pair per line. Line comments may be introduced by the hash
1601 character. This option may be given more than once.
1602
1603 @item --weaken
1604 Change all global symbols in the file to be weak. This can be useful
1605 when building an object which will be linked against other objects using
1606 the @option{-R} option to the linker. This option is only effective when
1607 using an object file format which supports weak symbols.
1608
1609 @item --keep-symbols=@var{filename}
1610 Apply @option{--keep-symbol} option to each symbol listed in the file
1611 @var{filename}. @var{filename} is simply a flat file, with one symbol
1612 name per line. Line comments may be introduced by the hash character.
1613 This option may be given more than once.
1614
1615 @item --strip-symbols=@var{filename}
1616 Apply @option{--strip-symbol} option to each symbol listed in the file
1617 @var{filename}. @var{filename} is simply a flat file, with one symbol
1618 name per line. Line comments may be introduced by the hash character.
1619 This option may be given more than once.
1620
1621 @item --strip-unneeded-symbols=@var{filename}
1622 Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1623 the file @var{filename}. @var{filename} is simply a flat file, with one
1624 symbol name per line. Line comments may be introduced by the hash
1625 character. This option may be given more than once.
1626
1627 @item --keep-global-symbols=@var{filename}
1628 Apply @option{--keep-global-symbol} option to each symbol listed in the
1629 file @var{filename}. @var{filename} is simply a flat file, with one
1630 symbol name per line. Line comments may be introduced by the hash
1631 character. This option may be given more than once.
1632
1633 @item --localize-symbols=@var{filename}
1634 Apply @option{--localize-symbol} option to each symbol listed in the file
1635 @var{filename}. @var{filename} is simply a flat file, with one symbol
1636 name per line. Line comments may be introduced by the hash character.
1637 This option may be given more than once.
1638
1639 @item --globalize-symbols=@var{filename}
1640 Apply @option{--globalize-symbol} option to each symbol listed in the file
1641 @var{filename}. @var{filename} is simply a flat file, with one symbol
1642 name per line. Line comments may be introduced by the hash character.
1643 This option may be given more than once.
1644
1645 @item --weaken-symbols=@var{filename}
1646 Apply @option{--weaken-symbol} option to each symbol listed in the file
1647 @var{filename}. @var{filename} is simply a flat file, with one symbol
1648 name per line. Line comments may be introduced by the hash character.
1649 This option may be given more than once.
1650
1651 @item --alt-machine-code=@var{index}
1652 If the output architecture has alternate machine codes, use the
1653 @var{index}th code instead of the default one. This is useful in case
1654 a machine is assigned an official code and the tool-chain adopts the
1655 new code, but other applications still depend on the original code
1656 being used. For ELF based architectures if the @var{index}
1657 alternative does not exist then the value is treated as an absolute
1658 number to be stored in the e_machine field of the ELF header.
1659
1660 @item --writable-text
1661 Mark the output text as writable. This option isn't meaningful for all
1662 object file formats.
1663
1664 @item --readonly-text
1665 Make the output text write protected. This option isn't meaningful for all
1666 object file formats.
1667
1668 @item --pure
1669 Mark the output file as demand paged. This option isn't meaningful for all
1670 object file formats.
1671
1672 @item --impure
1673 Mark the output file as impure. This option isn't meaningful for all
1674 object file formats.
1675
1676 @item --prefix-symbols=@var{string}
1677 Prefix all symbols in the output file with @var{string}.
1678
1679 @item --prefix-sections=@var{string}
1680 Prefix all section names in the output file with @var{string}.
1681
1682 @item --prefix-alloc-sections=@var{string}
1683 Prefix all the names of all allocated sections in the output file with
1684 @var{string}.
1685
1686 @item --add-gnu-debuglink=@var{path-to-file}
1687 Creates a .gnu_debuglink section which contains a reference to
1688 @var{path-to-file} and adds it to the output file. Note: the file at
1689 @var{path-to-file} must exist. Part of the process of adding the
1690 .gnu_debuglink section involves embedding a checksum of the contents
1691 of the debug info file into the section.
1692
1693 If the debug info file is built in one location but it is going to be
1694 installed at a later time into a different location then do not use
1695 the path to the installed location. The @option{--add-gnu-debuglink}
1696 option will fail because the installed file does not exist yet.
1697 Instead put the debug info file in the current directory and use the
1698 @option{--add-gnu-debuglink} option without any directory components,
1699 like this:
1700
1701 @smallexample
1702 objcopy --add-gnu-debuglink=foo.debug
1703 @end smallexample
1704
1705 At debug time the debugger will attempt to look for the separate debug
1706 info file in a set of known locations. The exact set of these
1707 locations varies depending upon the distribution being used, but it
1708 typically includes:
1709
1710 @table @code
1711
1712 @item * The same directory as the executable.
1713
1714 @item * A sub-directory of the directory containing the executable
1715 called .debug
1716
1717 @item * A global debug directory such as /usr/lib/debug.
1718 @end table
1719
1720 As long as the debug info file has been installed into one of these
1721 locations before the debugger is run everything should work
1722 correctly.
1723
1724 @item --keep-file-symbols
1725 When stripping a file, perhaps with @option{--strip-debug} or
1726 @option{--strip-unneeded}, retain any symbols specifying source file names,
1727 which would otherwise get stripped.
1728
1729 @item --only-keep-debug
1730 Strip a file, removing contents of any sections that would not be
1731 stripped by @option{--strip-debug} and leaving the debugging sections
1732 intact. In ELF files, this preserves all note sections in the output.
1733
1734 The intention is that this option will be used in conjunction with
1735 @option{--add-gnu-debuglink} to create a two part executable. One a
1736 stripped binary which will occupy less space in RAM and in a
1737 distribution and the second a debugging information file which is only
1738 needed if debugging abilities are required. The suggested procedure
1739 to create these files is as follows:
1740
1741 @enumerate
1742 @item Link the executable as normal. Assuming that is is called
1743 @code{foo} then...
1744 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
1745 create a file containing the debugging info.
1746 @item Run @code{objcopy --strip-debug foo} to create a
1747 stripped executable.
1748 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
1749 to add a link to the debugging info into the stripped executable.
1750 @end enumerate
1751
1752 Note---the choice of @code{.dbg} as an extension for the debug info
1753 file is arbitrary. Also the @code{--only-keep-debug} step is
1754 optional. You could instead do this:
1755
1756 @enumerate
1757 @item Link the executable as normal.
1758 @item Copy @code{foo} to @code{foo.full}
1759 @item Run @code{objcopy --strip-debug foo}
1760 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
1761 @end enumerate
1762
1763 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
1764 full executable. It does not have to be a file created by the
1765 @option{--only-keep-debug} switch.
1766
1767 Note---this switch is only intended for use on fully linked files. It
1768 does not make sense to use it on object files where the debugging
1769 information may be incomplete. Besides the gnu_debuglink feature
1770 currently only supports the presence of one filename containing
1771 debugging information, not multiple filenames on a one-per-object-file
1772 basis.
1773
1774 @item --strip-dwo
1775 Remove the contents of all DWARF .dwo sections, leaving the
1776 remaining debugging sections and all symbols intact.
1777 This option is intended for use by the compiler as part of
1778 the @option{-gsplit-dwarf} option, which splits debug information
1779 between the .o file and a separate .dwo file. The compiler
1780 generates all debug information in the same file, then uses
1781 the @option{--extract-dwo} option to copy the .dwo sections to
1782 the .dwo file, then the @option{--strip-dwo} option to remove
1783 those sections from the original .o file.
1784
1785 @item --extract-dwo
1786 Extract the contents of all DWARF .dwo sections. See the
1787 @option{--strip-dwo} option for more information.
1788
1789 @item --file-alignment @var{num}
1790 Specify the file alignment. Sections in the file will always begin at
1791 file offsets which are multiples of this number. This defaults to
1792 512.
1793 [This option is specific to PE targets.]
1794
1795 @item --heap @var{reserve}
1796 @itemx --heap @var{reserve},@var{commit}
1797 Specify the number of bytes of memory to reserve (and optionally commit)
1798 to be used as heap for this program.
1799 [This option is specific to PE targets.]
1800
1801 @item --image-base @var{value}
1802 Use @var{value} as the base address of your program or dll. This is
1803 the lowest memory location that will be used when your program or dll
1804 is loaded. To reduce the need to relocate and improve performance of
1805 your dlls, each should have a unique base address and not overlap any
1806 other dlls. The default is 0x400000 for executables, and 0x10000000
1807 for dlls.
1808 [This option is specific to PE targets.]
1809
1810 @item --section-alignment @var{num}
1811 Sets the section alignment. Sections in memory will always begin at
1812 addresses which are a multiple of this number. Defaults to 0x1000.
1813 [This option is specific to PE targets.]
1814
1815 @item --stack @var{reserve}
1816 @itemx --stack @var{reserve},@var{commit}
1817 Specify the number of bytes of memory to reserve (and optionally commit)
1818 to be used as stack for this program.
1819 [This option is specific to PE targets.]
1820
1821 @item --subsystem @var{which}
1822 @itemx --subsystem @var{which}:@var{major}
1823 @itemx --subsystem @var{which}:@var{major}.@var{minor}
1824 Specifies the subsystem under which your program will execute. The
1825 legal values for @var{which} are @code{native}, @code{windows},
1826 @code{console}, @code{posix}, @code{efi-app}, @code{efi-bsd},
1827 @code{efi-rtd}, @code{sal-rtd}, and @code{xbox}. You may optionally set
1828 the subsystem version also. Numeric values are also accepted for
1829 @var{which}.
1830 [This option is specific to PE targets.]
1831
1832 @item --extract-symbol
1833 Keep the file's section flags and symbols but remove all section data.
1834 Specifically, the option:
1835
1836 @itemize
1837 @item removes the contents of all sections;
1838 @item sets the size of every section to zero; and
1839 @item sets the file's start address to zero.
1840 @end itemize
1841
1842 This option is used to build a @file{.sym} file for a VxWorks kernel.
1843 It can also be a useful way of reducing the size of a @option{--just-symbols}
1844 linker input file.
1845
1846 @item --compress-debug-sections
1847 Compress DWARF debug sections using zlib. The debug sections are
1848 renamed to begin with @samp{.zdebug} instead of @samp{.debug}. Note -
1849 if compression would actually make a section @emph{larger} then it is
1850 not compressed or renamed.
1851
1852 @item --compress-debug-sections=none
1853 @itemx --compress-debug-sections=zlib
1854 @itemx --compress-debug-sections=zlib-gnu
1855 @itemx --compress-debug-sections=zlib-gabi
1856 For ELF files, these options control how DWARF debug sections are
1857 compressed. @option{--compress-debug-sections=none} is equivalent
1858 to @option{--nocompress-debug-sections}.
1859 @option{--compress-debug-sections=zlib} and
1860 @option{--compress-debug-sections=zlib-gnu} are equivalent to
1861 @option{--compress-debug-sections}.
1862 @option{--compress-debug-sections=zlib-gabi} compresses
1863 DWARF debug sections with SHF_COMPRESSED from the ELF ABI.
1864
1865 @item --decompress-debug-sections
1866 Decompress DWARF debug sections using zlib. The original section
1867 names of the compressed sections are restored.
1868
1869 @item -V
1870 @itemx --version
1871 Show the version number of @command{objcopy}.
1872
1873 @item -v
1874 @itemx --verbose
1875 Verbose output: list all object files modified. In the case of
1876 archives, @samp{objcopy -V} lists all members of the archive.
1877
1878 @item --help
1879 Show a summary of the options to @command{objcopy}.
1880
1881 @item --info
1882 Display a list showing all architectures and object formats available.
1883 @end table
1884
1885 @c man end
1886
1887 @ignore
1888 @c man begin SEEALSO objcopy
1889 ld(1), objdump(1), and the Info entries for @file{binutils}.
1890 @c man end
1891 @end ignore
1892
1893 @node objdump
1894 @chapter objdump
1895
1896 @cindex object file information
1897 @kindex objdump
1898
1899 @c man title objdump display information from object files.
1900
1901 @smallexample
1902 @c man begin SYNOPSIS objdump
1903 objdump [@option{-a}|@option{--archive-headers}]
1904 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
1905 [@option{-C}|@option{--demangle}[=@var{style}] ]
1906 [@option{-d}|@option{--disassemble}]
1907 [@option{-D}|@option{--disassemble-all}]
1908 [@option{-z}|@option{--disassemble-zeroes}]
1909 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
1910 [@option{-f}|@option{--file-headers}]
1911 [@option{-F}|@option{--file-offsets}]
1912 [@option{--file-start-context}]
1913 [@option{-g}|@option{--debugging}]
1914 [@option{-e}|@option{--debugging-tags}]
1915 [@option{-h}|@option{--section-headers}|@option{--headers}]
1916 [@option{-i}|@option{--info}]
1917 [@option{-j} @var{section}|@option{--section=}@var{section}]
1918 [@option{-l}|@option{--line-numbers}]
1919 [@option{-S}|@option{--source}]
1920 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
1921 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
1922 [@option{-p}|@option{--private-headers}]
1923 [@option{-P} @var{options}|@option{--private=}@var{options}]
1924 [@option{-r}|@option{--reloc}]
1925 [@option{-R}|@option{--dynamic-reloc}]
1926 [@option{-s}|@option{--full-contents}]
1927 [@option{-W[lLiaprmfFsoRt]}|
1928 @option{--dwarf}[=rawline,=decodedline,=info,=abbrev,=pubnames]
1929 [=aranges,=macro,=frames,=frames-interp,=str,=loc]
1930 [=Ranges,=pubtypes,=trace_info,=trace_abbrev]
1931 [=trace_aranges,=gdb_index]
1932 [@option{-G}|@option{--stabs}]
1933 [@option{-t}|@option{--syms}]
1934 [@option{-T}|@option{--dynamic-syms}]
1935 [@option{-x}|@option{--all-headers}]
1936 [@option{-w}|@option{--wide}]
1937 [@option{--start-address=}@var{address}]
1938 [@option{--stop-address=}@var{address}]
1939 [@option{--prefix-addresses}]
1940 [@option{--[no-]show-raw-insn}]
1941 [@option{--adjust-vma=}@var{offset}]
1942 [@option{--special-syms}]
1943 [@option{--prefix=}@var{prefix}]
1944 [@option{--prefix-strip=}@var{level}]
1945 [@option{--insn-width=}@var{width}]
1946 [@option{-V}|@option{--version}]
1947 [@option{-H}|@option{--help}]
1948 @var{objfile}@dots{}
1949 @c man end
1950 @end smallexample
1951
1952 @c man begin DESCRIPTION objdump
1953
1954 @command{objdump} displays information about one or more object files.
1955 The options control what particular information to display. This
1956 information is mostly useful to programmers who are working on the
1957 compilation tools, as opposed to programmers who just want their
1958 program to compile and work.
1959
1960 @var{objfile}@dots{} are the object files to be examined. When you
1961 specify archives, @command{objdump} shows information on each of the member
1962 object files.
1963
1964 @c man end
1965
1966 @c man begin OPTIONS objdump
1967
1968 The long and short forms of options, shown here as alternatives, are
1969 equivalent. At least one option from the list
1970 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-P,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
1971
1972 @table @env
1973 @item -a
1974 @itemx --archive-header
1975 @cindex archive headers
1976 If any of the @var{objfile} files are archives, display the archive
1977 header information (in a format similar to @samp{ls -l}). Besides the
1978 information you could list with @samp{ar tv}, @samp{objdump -a} shows
1979 the object file format of each archive member.
1980
1981 @item --adjust-vma=@var{offset}
1982 @cindex section addresses in objdump
1983 @cindex VMA in objdump
1984 When dumping information, first add @var{offset} to all the section
1985 addresses. This is useful if the section addresses do not correspond to
1986 the symbol table, which can happen when putting sections at particular
1987 addresses when using a format which can not represent section addresses,
1988 such as a.out.
1989
1990 @item -b @var{bfdname}
1991 @itemx --target=@var{bfdname}
1992 @cindex object code format
1993 Specify that the object-code format for the object files is
1994 @var{bfdname}. This option may not be necessary; @var{objdump} can
1995 automatically recognize many formats.
1996
1997 For example,
1998 @example
1999 objdump -b oasys -m vax -h fu.o
2000 @end example
2001 @noindent
2002 displays summary information from the section headers (@option{-h}) of
2003 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
2004 file in the format produced by Oasys compilers. You can list the
2005 formats available with the @option{-i} option.
2006 @xref{Target Selection}, for more information.
2007
2008 @item -C
2009 @itemx --demangle[=@var{style}]
2010 @cindex demangling in objdump
2011 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2012 Besides removing any initial underscore prepended by the system, this
2013 makes C++ function names readable. Different compilers have different
2014 mangling styles. The optional demangling style argument can be used to
2015 choose an appropriate demangling style for your compiler. @xref{c++filt},
2016 for more information on demangling.
2017
2018 @item -g
2019 @itemx --debugging
2020 Display debugging information. This attempts to parse STABS and IEEE
2021 debugging format information stored in the file and print it out using
2022 a C like syntax. If neither of these formats are found this option
2023 falls back on the @option{-W} option to print any DWARF information in
2024 the file.
2025
2026 @item -e
2027 @itemx --debugging-tags
2028 Like @option{-g}, but the information is generated in a format compatible
2029 with ctags tool.
2030
2031 @item -d
2032 @itemx --disassemble
2033 @cindex disassembling object code
2034 @cindex machine instructions
2035 Display the assembler mnemonics for the machine instructions from
2036 @var{objfile}. This option only disassembles those sections which are
2037 expected to contain instructions.
2038
2039 @item -D
2040 @itemx --disassemble-all
2041 Like @option{-d}, but disassemble the contents of all sections, not just
2042 those expected to contain instructions.
2043
2044 If the target is an ARM architecture this switch also has the effect
2045 of forcing the disassembler to decode pieces of data found in code
2046 sections as if they were instructions.
2047
2048 @item --prefix-addresses
2049 When disassembling, print the complete address on each line. This is
2050 the older disassembly format.
2051
2052 @item -EB
2053 @itemx -EL
2054 @itemx --endian=@{big|little@}
2055 @cindex endianness
2056 @cindex disassembly endianness
2057 Specify the endianness of the object files. This only affects
2058 disassembly. This can be useful when disassembling a file format which
2059 does not describe endianness information, such as S-records.
2060
2061 @item -f
2062 @itemx --file-headers
2063 @cindex object file header
2064 Display summary information from the overall header of
2065 each of the @var{objfile} files.
2066
2067 @item -F
2068 @itemx --file-offsets
2069 @cindex object file offsets
2070 When disassembling sections, whenever a symbol is displayed, also
2071 display the file offset of the region of data that is about to be
2072 dumped. If zeroes are being skipped, then when disassembly resumes,
2073 tell the user how many zeroes were skipped and the file offset of the
2074 location from where the disassembly resumes. When dumping sections,
2075 display the file offset of the location from where the dump starts.
2076
2077 @item --file-start-context
2078 @cindex source code context
2079 Specify that when displaying interlisted source code/disassembly
2080 (assumes @option{-S}) from a file that has not yet been displayed, extend the
2081 context to the start of the file.
2082
2083 @item -h
2084 @itemx --section-headers
2085 @itemx --headers
2086 @cindex section headers
2087 Display summary information from the section headers of the
2088 object file.
2089
2090 File segments may be relocated to nonstandard addresses, for example by
2091 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
2092 @command{ld}. However, some object file formats, such as a.out, do not
2093 store the starting address of the file segments. In those situations,
2094 although @command{ld} relocates the sections correctly, using @samp{objdump
2095 -h} to list the file section headers cannot show the correct addresses.
2096 Instead, it shows the usual addresses, which are implicit for the
2097 target.
2098
2099 @item -H
2100 @itemx --help
2101 Print a summary of the options to @command{objdump} and exit.
2102
2103 @item -i
2104 @itemx --info
2105 @cindex architectures available
2106 @cindex object formats available
2107 Display a list showing all architectures and object formats available
2108 for specification with @option{-b} or @option{-m}.
2109
2110 @item -j @var{name}
2111 @itemx --section=@var{name}
2112 @cindex section information
2113 Display information only for section @var{name}.
2114
2115 @item -l
2116 @itemx --line-numbers
2117 @cindex source filenames for object files
2118 Label the display (using debugging information) with the filename and
2119 source line numbers corresponding to the object code or relocs shown.
2120 Only useful with @option{-d}, @option{-D}, or @option{-r}.
2121
2122 @item -m @var{machine}
2123 @itemx --architecture=@var{machine}
2124 @cindex architecture
2125 @cindex disassembly architecture
2126 Specify the architecture to use when disassembling object files. This
2127 can be useful when disassembling object files which do not describe
2128 architecture information, such as S-records. You can list the available
2129 architectures with the @option{-i} option.
2130
2131 If the target is an ARM architecture then this switch has an
2132 additional effect. It restricts the disassembly to only those
2133 instructions supported by the architecture specified by @var{machine}.
2134 If it is necessary to use this switch because the input file does not
2135 contain any architecture information, but it is also desired to
2136 disassemble all the instructions use @option{-marm}.
2137
2138 @item -M @var{options}
2139 @itemx --disassembler-options=@var{options}
2140 Pass target specific information to the disassembler. Only supported on
2141 some targets. If it is necessary to specify more than one
2142 disassembler option then multiple @option{-M} options can be used or
2143 can be placed together into a comma separated list.
2144
2145 If the target is an ARM architecture then this switch can be used to
2146 select which register name set is used during disassembler. Specifying
2147 @option{-M reg-names-std} (the default) will select the register names as
2148 used in ARM's instruction set documentation, but with register 13 called
2149 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
2150 @option{-M reg-names-apcs} will select the name set used by the ARM
2151 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
2152 just use @samp{r} followed by the register number.
2153
2154 There are also two variants on the APCS register naming scheme enabled
2155 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
2156 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
2157 with the normal register names or the special register names).
2158
2159 This option can also be used for ARM architectures to force the
2160 disassembler to interpret all instructions as Thumb instructions by
2161 using the switch @option{--disassembler-options=force-thumb}. This can be
2162 useful when attempting to disassemble thumb code produced by other
2163 compilers.
2164
2165 For the x86, some of the options duplicate functions of the @option{-m}
2166 switch, but allow finer grained control. Multiple selections from the
2167 following may be specified as a comma separated string.
2168 @table @code
2169 @item x86-64
2170 @itemx i386
2171 @itemx i8086
2172 Select disassembly for the given architecture.
2173
2174 @item intel
2175 @itemx att
2176 Select between intel syntax mode and AT&T syntax mode.
2177
2178 @item amd64
2179 @itemx intel64
2180 Select between AMD64 ISA and Intel64 ISA.
2181
2182 @item intel-mnemonic
2183 @itemx att-mnemonic
2184 Select between intel mnemonic mode and AT&T mnemonic mode.
2185 Note: @code{intel-mnemonic} implies @code{intel} and
2186 @code{att-mnemonic} implies @code{att}.
2187
2188 @item addr64
2189 @itemx addr32
2190 @itemx addr16
2191 @itemx data32
2192 @itemx data16
2193 Specify the default address size and operand size. These four options
2194 will be overridden if @code{x86-64}, @code{i386} or @code{i8086}
2195 appear later in the option string.
2196
2197 @item suffix
2198 When in AT&T mode, instructs the disassembler to print a mnemonic
2199 suffix even when the suffix could be inferred by the operands.
2200 @end table
2201
2202 For PowerPC, @option{booke} controls the disassembly of BookE
2203 instructions. @option{32} and @option{64} select PowerPC and
2204 PowerPC64 disassembly, respectively. @option{e300} selects
2205 disassembly for the e300 family. @option{440} selects disassembly for
2206 the PowerPC 440. @option{ppcps} selects disassembly for the paired
2207 single instructions of the PPC750CL.
2208
2209 For MIPS, this option controls the printing of instruction mnemonic
2210 names and register names in disassembled instructions. Multiple
2211 selections from the following may be specified as a comma separated
2212 string, and invalid options are ignored:
2213
2214 @table @code
2215 @item no-aliases
2216 Print the 'raw' instruction mnemonic instead of some pseudo
2217 instruction mnemonic. I.e., print 'daddu' or 'or' instead of 'move',
2218 'sll' instead of 'nop', etc.
2219
2220 @item msa
2221 Disassemble MSA instructions.
2222
2223 @item virt
2224 Disassemble the virtualization ASE instructions.
2225
2226 @item xpa
2227 Disassemble the eXtended Physical Address (XPA) ASE instructions.
2228
2229 @item gpr-names=@var{ABI}
2230 Print GPR (general-purpose register) names as appropriate
2231 for the specified ABI. By default, GPR names are selected according to
2232 the ABI of the binary being disassembled.
2233
2234 @item fpr-names=@var{ABI}
2235 Print FPR (floating-point register) names as
2236 appropriate for the specified ABI. By default, FPR numbers are printed
2237 rather than names.
2238
2239 @item cp0-names=@var{ARCH}
2240 Print CP0 (system control coprocessor; coprocessor 0) register names
2241 as appropriate for the CPU or architecture specified by
2242 @var{ARCH}. By default, CP0 register names are selected according to
2243 the architecture and CPU of the binary being disassembled.
2244
2245 @item hwr-names=@var{ARCH}
2246 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
2247 as appropriate for the CPU or architecture specified by
2248 @var{ARCH}. By default, HWR names are selected according to
2249 the architecture and CPU of the binary being disassembled.
2250
2251 @item reg-names=@var{ABI}
2252 Print GPR and FPR names as appropriate for the selected ABI.
2253
2254 @item reg-names=@var{ARCH}
2255 Print CPU-specific register names (CP0 register and HWR names)
2256 as appropriate for the selected CPU or architecture.
2257 @end table
2258
2259 For any of the options listed above, @var{ABI} or
2260 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
2261 rather than names, for the selected types of registers.
2262 You can list the available values of @var{ABI} and @var{ARCH} using
2263 the @option{--help} option.
2264
2265 For VAX, you can specify function entry addresses with @option{-M
2266 entry:0xf00ba}. You can use this multiple times to properly
2267 disassemble VAX binary files that don't contain symbol tables (like
2268 ROM dumps). In these cases, the function entry mask would otherwise
2269 be decoded as VAX instructions, which would probably lead the rest
2270 of the function being wrongly disassembled.
2271
2272 @item -p
2273 @itemx --private-headers
2274 Print information that is specific to the object file format. The exact
2275 information printed depends upon the object file format. For some
2276 object file formats, no additional information is printed.
2277
2278 @item -P @var{options}
2279 @itemx --private=@var{options}
2280 Print information that is specific to the object file format. The
2281 argument @var{options} is a comma separated list that depends on the
2282 format (the lists of options is displayed with the help).
2283
2284 For XCOFF, the available options are:
2285 @table @code
2286 @item header
2287 @item aout
2288 @item sections
2289 @item syms
2290 @item relocs
2291 @item lineno,
2292 @item loader
2293 @item except
2294 @item typchk
2295 @item traceback
2296 @item toc
2297 @item ldinfo
2298 @end table
2299
2300 Not all object formats support this option. In particular the ELF
2301 format does not use it.
2302
2303 @item -r
2304 @itemx --reloc
2305 @cindex relocation entries, in object file
2306 Print the relocation entries of the file. If used with @option{-d} or
2307 @option{-D}, the relocations are printed interspersed with the
2308 disassembly.
2309
2310 @item -R
2311 @itemx --dynamic-reloc
2312 @cindex dynamic relocation entries, in object file
2313 Print the dynamic relocation entries of the file. This is only
2314 meaningful for dynamic objects, such as certain types of shared
2315 libraries. As for @option{-r}, if used with @option{-d} or
2316 @option{-D}, the relocations are printed interspersed with the
2317 disassembly.
2318
2319 @item -s
2320 @itemx --full-contents
2321 @cindex sections, full contents
2322 @cindex object file sections
2323 Display the full contents of any sections requested. By default all
2324 non-empty sections are displayed.
2325
2326 @item -S
2327 @itemx --source
2328 @cindex source disassembly
2329 @cindex disassembly, with source
2330 Display source code intermixed with disassembly, if possible. Implies
2331 @option{-d}.
2332
2333 @item --prefix=@var{prefix}
2334 @cindex Add prefix to absolute paths
2335 Specify @var{prefix} to add to the absolute paths when used with
2336 @option{-S}.
2337
2338 @item --prefix-strip=@var{level}
2339 @cindex Strip absolute paths
2340 Indicate how many initial directory names to strip off the hardwired
2341 absolute paths. It has no effect without @option{--prefix=}@var{prefix}.
2342
2343 @item --show-raw-insn
2344 When disassembling instructions, print the instruction in hex as well as
2345 in symbolic form. This is the default except when
2346 @option{--prefix-addresses} is used.
2347
2348 @item --no-show-raw-insn
2349 When disassembling instructions, do not print the instruction bytes.
2350 This is the default when @option{--prefix-addresses} is used.
2351
2352 @item --insn-width=@var{width}
2353 @cindex Instruction width
2354 Display @var{width} bytes on a single line when disassembling
2355 instructions.
2356
2357 @item -W[lLiaprmfFsoRt]
2358 @itemx --dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames]
2359 @itemx --dwarf[=aranges,=macro,=frames,=frames-interp,=str,=loc]
2360 @itemx --dwarf[=Ranges,=pubtypes,=trace_info,=trace_abbrev]
2361 @itemx --dwarf[=trace_aranges,=gdb_index]
2362 @cindex DWARF
2363 @cindex debug symbols
2364 Displays the contents of the debug sections in the file, if any are
2365 present. If one of the optional letters or words follows the switch
2366 then only data found in those specific sections will be dumped.
2367
2368 Note that there is no single letter option to display the content of
2369 trace sections or .gdb_index.
2370
2371 Note: the output from the @option{=info} option can also be affected
2372 by the options @option{--dwarf-depth}, the @option{--dwarf-start} and
2373 the @option{--dwarf-check}.
2374
2375 @item --dwarf-depth=@var{n}
2376 Limit the dump of the @code{.debug_info} section to @var{n} children.
2377 This is only useful with @option{--dwarf=info}. The default is
2378 to print all DIEs; the special value 0 for @var{n} will also have this
2379 effect.
2380
2381 With a non-zero value for @var{n}, DIEs at or deeper than @var{n}
2382 levels will not be printed. The range for @var{n} is zero-based.
2383
2384 @item --dwarf-start=@var{n}
2385 Print only DIEs beginning with the DIE numbered @var{n}. This is only
2386 useful with @option{--dwarf=info}.
2387
2388 If specified, this option will suppress printing of any header
2389 information and all DIEs before the DIE numbered @var{n}. Only
2390 siblings and children of the specified DIE will be printed.
2391
2392 This can be used in conjunction with @option{--dwarf-depth}.
2393
2394 @item --dwarf-check
2395 Enable additional checks for consistency of Dwarf information.
2396
2397 @item -G
2398 @itemx --stabs
2399 @cindex stab
2400 @cindex .stab
2401 @cindex debug symbols
2402 @cindex ELF object file format
2403 Display the full contents of any sections requested. Display the
2404 contents of the .stab and .stab.index and .stab.excl sections from an
2405 ELF file. This is only useful on systems (such as Solaris 2.0) in which
2406 @code{.stab} debugging symbol-table entries are carried in an ELF
2407 section. In most other file formats, debugging symbol-table entries are
2408 interleaved with linkage symbols, and are visible in the @option{--syms}
2409 output.
2410
2411 @item --start-address=@var{address}
2412 @cindex start-address
2413 Start displaying data at the specified address. This affects the output
2414 of the @option{-d}, @option{-r} and @option{-s} options.
2415
2416 @item --stop-address=@var{address}
2417 @cindex stop-address
2418 Stop displaying data at the specified address. This affects the output
2419 of the @option{-d}, @option{-r} and @option{-s} options.
2420
2421 @item -t
2422 @itemx --syms
2423 @cindex symbol table entries, printing
2424 Print the symbol table entries of the file.
2425 This is similar to the information provided by the @samp{nm} program,
2426 although the display format is different. The format of the output
2427 depends upon the format of the file being dumped, but there are two main
2428 types. One looks like this:
2429
2430 @smallexample
2431 [ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss
2432 [ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred
2433 @end smallexample
2434
2435 where the number inside the square brackets is the number of the entry
2436 in the symbol table, the @var{sec} number is the section number, the
2437 @var{fl} value are the symbol's flag bits, the @var{ty} number is the
2438 symbol's type, the @var{scl} number is the symbol's storage class and
2439 the @var{nx} value is the number of auxilary entries associated with
2440 the symbol. The last two fields are the symbol's value and its name.
2441
2442 The other common output format, usually seen with ELF based files,
2443 looks like this:
2444
2445 @smallexample
2446 00000000 l d .bss 00000000 .bss
2447 00000000 g .text 00000000 fred
2448 @end smallexample
2449
2450 Here the first number is the symbol's value (sometimes refered to as
2451 its address). The next field is actually a set of characters and
2452 spaces indicating the flag bits that are set on the symbol. These
2453 characters are described below. Next is the section with which the
2454 symbol is associated or @emph{*ABS*} if the section is absolute (ie
2455 not connected with any section), or @emph{*UND*} if the section is
2456 referenced in the file being dumped, but not defined there.
2457
2458 After the section name comes another field, a number, which for common
2459 symbols is the alignment and for other symbol is the size. Finally
2460 the symbol's name is displayed.
2461
2462 The flag characters are divided into 7 groups as follows:
2463 @table @code
2464 @item l
2465 @itemx g
2466 @itemx u
2467 @itemx !
2468 The symbol is a local (l), global (g), unique global (u), neither
2469 global nor local (a space) or both global and local (!). A
2470 symbol can be neither local or global for a variety of reasons, e.g.,
2471 because it is used for debugging, but it is probably an indication of
2472 a bug if it is ever both local and global. Unique global symbols are
2473 a GNU extension to the standard set of ELF symbol bindings. For such
2474 a symbol the dynamic linker will make sure that in the entire process
2475 there is just one symbol with this name and type in use.
2476
2477 @item w
2478 The symbol is weak (w) or strong (a space).
2479
2480 @item C
2481 The symbol denotes a constructor (C) or an ordinary symbol (a space).
2482
2483 @item W
2484 The symbol is a warning (W) or a normal symbol (a space). A warning
2485 symbol's name is a message to be displayed if the symbol following the
2486 warning symbol is ever referenced.
2487
2488 @item I
2489 @item i
2490 The symbol is an indirect reference to another symbol (I), a function
2491 to be evaluated during reloc processing (i) or a normal symbol (a
2492 space).
2493
2494 @item d
2495 @itemx D
2496 The symbol is a debugging symbol (d) or a dynamic symbol (D) or a
2497 normal symbol (a space).
2498
2499 @item F
2500 @item f
2501 @item O
2502 The symbol is the name of a function (F) or a file (f) or an object
2503 (O) or just a normal symbol (a space).
2504 @end table
2505
2506 @item -T
2507 @itemx --dynamic-syms
2508 @cindex dynamic symbol table entries, printing
2509 Print the dynamic symbol table entries of the file. This is only
2510 meaningful for dynamic objects, such as certain types of shared
2511 libraries. This is similar to the information provided by the @samp{nm}
2512 program when given the @option{-D} (@option{--dynamic}) option.
2513
2514 @item --special-syms
2515 When displaying symbols include those which the target considers to be
2516 special in some way and which would not normally be of interest to the
2517 user.
2518
2519 @item -V
2520 @itemx --version
2521 Print the version number of @command{objdump} and exit.
2522
2523 @item -x
2524 @itemx --all-headers
2525 @cindex all header information, object file
2526 @cindex header information, all
2527 Display all available header information, including the symbol table and
2528 relocation entries. Using @option{-x} is equivalent to specifying all of
2529 @option{-a -f -h -p -r -t}.
2530
2531 @item -w
2532 @itemx --wide
2533 @cindex wide output, printing
2534 Format some lines for output devices that have more than 80 columns.
2535 Also do not truncate symbol names when they are displayed.
2536
2537 @item -z
2538 @itemx --disassemble-zeroes
2539 Normally the disassembly output will skip blocks of zeroes. This
2540 option directs the disassembler to disassemble those blocks, just like
2541 any other data.
2542 @end table
2543
2544 @c man end
2545
2546 @ignore
2547 @c man begin SEEALSO objdump
2548 nm(1), readelf(1), and the Info entries for @file{binutils}.
2549 @c man end
2550 @end ignore
2551
2552 @node ranlib
2553 @chapter ranlib
2554
2555 @kindex ranlib
2556 @cindex archive contents
2557 @cindex symbol index
2558
2559 @c man title ranlib generate index to archive.
2560
2561 @smallexample
2562 @c man begin SYNOPSIS ranlib
2563 ranlib [@option{--plugin} @var{name}] [@option{-DhHvVt}] @var{archive}
2564 @c man end
2565 @end smallexample
2566
2567 @c man begin DESCRIPTION ranlib
2568
2569 @command{ranlib} generates an index to the contents of an archive and
2570 stores it in the archive. The index lists each symbol defined by a
2571 member of an archive that is a relocatable object file.
2572
2573 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
2574
2575 An archive with such an index speeds up linking to the library and
2576 allows routines in the library to call each other without regard to
2577 their placement in the archive.
2578
2579 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
2580 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
2581 @xref{ar}.
2582
2583 @c man end
2584
2585 @c man begin OPTIONS ranlib
2586
2587 @table @env
2588 @item -h
2589 @itemx -H
2590 @itemx --help
2591 Show usage information for @command{ranlib}.
2592
2593 @item -v
2594 @itemx -V
2595 @itemx --version
2596 Show the version number of @command{ranlib}.
2597
2598 @item -D
2599 @cindex deterministic archives
2600 @kindex --enable-deterministic-archives
2601 Operate in @emph{deterministic} mode. The symbol map archive member's
2602 header will show zero for the UID, GID, and timestamp. When this
2603 option is used, multiple runs will produce identical output files.
2604
2605 If @file{binutils} was configured with
2606 @option{--enable-deterministic-archives}, then this mode is on by
2607 default. It can be disabled with the @samp{-U} option, described
2608 below.
2609
2610 @item -t
2611 Update the timestamp of the symbol map of an archive.
2612
2613 @item -U
2614 @cindex deterministic archives
2615 @kindex --enable-deterministic-archives
2616 Do @emph{not} operate in @emph{deterministic} mode. This is the
2617 inverse of the @samp{-D} option, above: the archive index will get
2618 actual UID, GID, timestamp, and file mode values.
2619
2620 If @file{binutils} was configured @emph{without}
2621 @option{--enable-deterministic-archives}, then this mode is on by
2622 default.
2623
2624 @end table
2625
2626 @c man end
2627
2628 @ignore
2629 @c man begin SEEALSO ranlib
2630 ar(1), nm(1), and the Info entries for @file{binutils}.
2631 @c man end
2632 @end ignore
2633
2634 @node size
2635 @chapter size
2636
2637 @kindex size
2638 @cindex section sizes
2639
2640 @c man title size list section sizes and total size.
2641
2642 @smallexample
2643 @c man begin SYNOPSIS size
2644 size [@option{-A}|@option{-B}|@option{--format=}@var{compatibility}]
2645 [@option{--help}]
2646 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
2647 [@option{--common}]
2648 [@option{-t}|@option{--totals}]
2649 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
2650 [@var{objfile}@dots{}]
2651 @c man end
2652 @end smallexample
2653
2654 @c man begin DESCRIPTION size
2655
2656 The @sc{gnu} @command{size} utility lists the section sizes---and the total
2657 size---for each of the object or archive files @var{objfile} in its
2658 argument list. By default, one line of output is generated for each
2659 object file or each module in an archive.
2660
2661 @var{objfile}@dots{} are the object files to be examined.
2662 If none are specified, the file @code{a.out} will be used.
2663
2664 @c man end
2665
2666 @c man begin OPTIONS size
2667
2668 The command line options have the following meanings:
2669
2670 @table @env
2671 @item -A
2672 @itemx -B
2673 @itemx --format=@var{compatibility}
2674 @cindex @command{size} display format
2675 Using one of these options, you can choose whether the output from @sc{gnu}
2676 @command{size} resembles output from System V @command{size} (using @option{-A},
2677 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
2678 @option{--format=berkeley}). The default is the one-line format similar to
2679 Berkeley's.
2680 @c Bonus for doc-source readers: you can also say --format=strange (or
2681 @c anything else that starts with 's') for sysv, and --format=boring (or
2682 @c anything else that starts with 'b') for Berkeley.
2683
2684 Here is an example of the Berkeley (default) format of output from
2685 @command{size}:
2686 @smallexample
2687 $ size --format=Berkeley ranlib size
2688 text data bss dec hex filename
2689 294880 81920 11592 388392 5ed28 ranlib
2690 294880 81920 11888 388688 5ee50 size
2691 @end smallexample
2692
2693 @noindent
2694 This is the same data, but displayed closer to System V conventions:
2695
2696 @smallexample
2697 $ size --format=SysV ranlib size
2698 ranlib :
2699 section size addr
2700 .text 294880 8192
2701 .data 81920 303104
2702 .bss 11592 385024
2703 Total 388392
2704
2705
2706 size :
2707 section size addr
2708 .text 294880 8192
2709 .data 81920 303104
2710 .bss 11888 385024
2711 Total 388688
2712 @end smallexample
2713
2714 @item --help
2715 Show a summary of acceptable arguments and options.
2716
2717 @item -d
2718 @itemx -o
2719 @itemx -x
2720 @itemx --radix=@var{number}
2721 @cindex @command{size} number format
2722 @cindex radix for section sizes
2723 Using one of these options, you can control whether the size of each
2724 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
2725 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
2726 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
2727 values (8, 10, 16) are supported. The total size is always given in two
2728 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
2729 octal and hexadecimal if you're using @option{-o}.
2730
2731 @item --common
2732 Print total size of common symbols in each file. When using Berkeley
2733 format these are included in the bss size.
2734
2735 @item -t
2736 @itemx --totals
2737 Show totals of all objects listed (Berkeley format listing mode only).
2738
2739 @item --target=@var{bfdname}
2740 @cindex object code format
2741 Specify that the object-code format for @var{objfile} is
2742 @var{bfdname}. This option may not be necessary; @command{size} can
2743 automatically recognize many formats.
2744 @xref{Target Selection}, for more information.
2745
2746 @item -V
2747 @itemx --version
2748 Display the version number of @command{size}.
2749 @end table
2750
2751 @c man end
2752
2753 @ignore
2754 @c man begin SEEALSO size
2755 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
2756 @c man end
2757 @end ignore
2758
2759 @node strings
2760 @chapter strings
2761 @kindex strings
2762 @cindex listings strings
2763 @cindex printing strings
2764 @cindex strings, printing
2765
2766 @c man title strings print the strings of printable characters in files.
2767
2768 @smallexample
2769 @c man begin SYNOPSIS strings
2770 strings [@option{-afovV}] [@option{-}@var{min-len}]
2771 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
2772 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
2773 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
2774 [@option{-}] [@option{--all}] [@option{--print-file-name}]
2775 [@option{-T} @var{bfdname}] [@option{--target=}@var{bfdname}]
2776 [@option{-w}] [@option{--include-all-whitespace}]
2777 [@option{--help}] [@option{--version}] @var{file}@dots{}
2778 @c man end
2779 @end smallexample
2780
2781 @c man begin DESCRIPTION strings
2782
2783 For each @var{file} given, @sc{gnu} @command{strings} prints the
2784 printable character sequences that are at least 4 characters long (or
2785 the number given with the options below) and are followed by an
2786 unprintable character.
2787
2788 Depending upon how the strings program was configured it will default
2789 to either displaying all the printable sequences that it can find in
2790 each file, or only those sequences that are in loadable, initialized
2791 data sections. If the file type in unrecognizable, or if strings is
2792 reading from stdin then it will always display all of the printable
2793 sequences that it can find.
2794
2795 For backwards compatibility any file that occurs after a command line
2796 option of just @option{-} will also be scanned in full, regardless of
2797 the presence of any @option{-d} option.
2798
2799 @command{strings} is mainly useful for determining the contents of
2800 non-text files.
2801
2802 @c man end
2803
2804 @c man begin OPTIONS strings
2805
2806 @table @env
2807 @item -a
2808 @itemx --all
2809 @itemx -
2810 Scan the whole file, regardless of what sections it contains or
2811 whether those sections are loaded or initialized. Normally this is
2812 the default behaviour, but strings can be configured so that the
2813 @option{-d} is the default instead.
2814
2815 The @option{-} option is position dependent and forces strings to
2816 perform full scans of any file that is mentioned after the @option{-}
2817 on the command line, even if the @option{-d} option has been
2818 specified.
2819
2820 @item -d
2821 @itemx --data
2822 Only print strings from initialized, loaded data sections in the
2823 file. This may reduce the amount of garbage in the output, but it
2824 also exposes the strings program to any security flaws that may be
2825 present in the BFD library used to scan and load sections. Strings
2826 can be configured so that this option is the default behaviour. In
2827 such cases the @option{-a} option can be used to avoid using the BFD
2828 library and instead just print all of the strings found in the file.
2829
2830 @item -f
2831 @itemx --print-file-name
2832 Print the name of the file before each string.
2833
2834 @item --help
2835 Print a summary of the program usage on the standard output and exit.
2836
2837 @item -@var{min-len}
2838 @itemx -n @var{min-len}
2839 @itemx --bytes=@var{min-len}
2840 Print sequences of characters that are at least @var{min-len} characters
2841 long, instead of the default 4.
2842
2843 @item -o
2844 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
2845 act like @samp{-t d} instead. Since we can not be compatible with both
2846 ways, we simply chose one.
2847
2848 @item -t @var{radix}
2849 @itemx --radix=@var{radix}
2850 Print the offset within the file before each string. The single
2851 character argument specifies the radix of the offset---@samp{o} for
2852 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
2853
2854 @item -e @var{encoding}
2855 @itemx --encoding=@var{encoding}
2856 Select the character encoding of the strings that are to be found.
2857 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
2858 characters (ASCII, ISO 8859, etc., default), @samp{S} =
2859 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
2860 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
2861 littleendian. Useful for finding wide character strings. (@samp{l}
2862 and @samp{b} apply to, for example, Unicode UTF-16/UCS-2 encodings).
2863
2864 @item -T @var{bfdname}
2865 @itemx --target=@var{bfdname}
2866 @cindex object code format
2867 Specify an object code format other than your system's default format.
2868 @xref{Target Selection}, for more information.
2869
2870 @item -v
2871 @itemx -V
2872 @itemx --version
2873 Print the program version number on the standard output and exit.
2874
2875 @item -w
2876 @itemx --include-all-whitespace
2877 By default tab and space characters are included in the strings that
2878 are displayed, but other whitespace characters, such a newlines and
2879 carriage returns, are not. The @option{-w} option changes this so
2880 that all whitespace characters are considered to be part of a string.
2881 @end table
2882
2883 @c man end
2884
2885 @ignore
2886 @c man begin SEEALSO strings
2887 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
2888 and the Info entries for @file{binutils}.
2889 @c man end
2890 @end ignore
2891
2892 @node strip
2893 @chapter strip
2894
2895 @kindex strip
2896 @cindex removing symbols
2897 @cindex discarding symbols
2898 @cindex symbols, discarding
2899
2900 @c man title strip Discard symbols from object files.
2901
2902 @smallexample
2903 @c man begin SYNOPSIS strip
2904 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
2905 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
2906 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
2907 [@option{-s}|@option{--strip-all}]
2908 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
2909 [@option{--strip-dwo}]
2910 [@option{-K} @var{symbolname} |@option{--keep-symbol=}@var{symbolname}]
2911 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
2912 [@option{-w}|@option{--wildcard}]
2913 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
2914 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
2915 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
2916 [@option{-D}|@option{--enable-deterministic-archives}]
2917 [@option{-U}|@option{--disable-deterministic-archives}]
2918 [@option{--keep-file-symbols}]
2919 [@option{--only-keep-debug}]
2920 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
2921 [@option{--help}] [@option{--info}]
2922 @var{objfile}@dots{}
2923 @c man end
2924 @end smallexample
2925
2926 @c man begin DESCRIPTION strip
2927
2928 @sc{gnu} @command{strip} discards all symbols from object files
2929 @var{objfile}. The list of object files may include archives.
2930 At least one object file must be given.
2931
2932 @command{strip} modifies the files named in its argument,
2933 rather than writing modified copies under different names.
2934
2935 @c man end
2936
2937 @c man begin OPTIONS strip
2938
2939 @table @env
2940 @item -F @var{bfdname}
2941 @itemx --target=@var{bfdname}
2942 Treat the original @var{objfile} as a file with the object
2943 code format @var{bfdname}, and rewrite it in the same format.
2944 @xref{Target Selection}, for more information.
2945
2946 @item --help
2947 Show a summary of the options to @command{strip} and exit.
2948
2949 @item --info
2950 Display a list showing all architectures and object formats available.
2951
2952 @item -I @var{bfdname}
2953 @itemx --input-target=@var{bfdname}
2954 Treat the original @var{objfile} as a file with the object
2955 code format @var{bfdname}.
2956 @xref{Target Selection}, for more information.
2957
2958 @item -O @var{bfdname}
2959 @itemx --output-target=@var{bfdname}
2960 Replace @var{objfile} with a file in the output format @var{bfdname}.
2961 @xref{Target Selection}, for more information.
2962
2963 @item -R @var{sectionname}
2964 @itemx --remove-section=@var{sectionname}
2965 Remove any section named @var{sectionname} from the output file, in
2966 addition to whatever sections would otherwise be removed. This
2967 option may be given more than once. Note that using this option
2968 inappropriately may make the output file unusable. The wildcard
2969 character @samp{*} may be given at the end of @var{sectionname}. If
2970 so, then any section starting with @var{sectionname} will be removed.
2971
2972 @item -s
2973 @itemx --strip-all
2974 Remove all symbols.
2975
2976 @item -g
2977 @itemx -S
2978 @itemx -d
2979 @itemx --strip-debug
2980 Remove debugging symbols only.
2981
2982 @item --strip-dwo
2983 Remove the contents of all DWARF .dwo sections, leaving the
2984 remaining debugging sections and all symbols intact.
2985 See the description of this option in the @command{objcopy} section
2986 for more information.
2987
2988 @item --strip-unneeded
2989 Remove all symbols that are not needed for relocation processing.
2990
2991 @item -K @var{symbolname}
2992 @itemx --keep-symbol=@var{symbolname}
2993 When stripping symbols, keep symbol @var{symbolname} even if it would
2994 normally be stripped. This option may be given more than once.
2995
2996 @item -N @var{symbolname}
2997 @itemx --strip-symbol=@var{symbolname}
2998 Remove symbol @var{symbolname} from the source file. This option may be
2999 given more than once, and may be combined with strip options other than
3000 @option{-K}.
3001
3002 @item -o @var{file}
3003 Put the stripped output in @var{file}, rather than replacing the
3004 existing file. When this argument is used, only one @var{objfile}
3005 argument may be specified.
3006
3007 @item -p
3008 @itemx --preserve-dates
3009 Preserve the access and modification dates of the file.
3010
3011 @item -D
3012 @itemx --enable-deterministic-archives
3013 @cindex deterministic archives
3014 @kindex --enable-deterministic-archives
3015 Operate in @emph{deterministic} mode. When copying archive members
3016 and writing the archive index, use zero for UIDs, GIDs, timestamps,
3017 and use consistent file modes for all files.
3018
3019 If @file{binutils} was configured with
3020 @option{--enable-deterministic-archives}, then this mode is on by default.
3021 It can be disabled with the @samp{-U} option, below.
3022
3023 @item -U
3024 @itemx --disable-deterministic-archives
3025 @cindex deterministic archives
3026 @kindex --enable-deterministic-archives
3027 Do @emph{not} operate in @emph{deterministic} mode. This is the
3028 inverse of the @option{-D} option, above: when copying archive members
3029 and writing the archive index, use their actual UID, GID, timestamp,
3030 and file mode values.
3031
3032 This is the default unless @file{binutils} was configured with
3033 @option{--enable-deterministic-archives}.
3034
3035 @item -w
3036 @itemx --wildcard
3037 Permit regular expressions in @var{symbolname}s used in other command
3038 line options. The question mark (?), asterisk (*), backslash (\) and
3039 square brackets ([]) operators can be used anywhere in the symbol
3040 name. If the first character of the symbol name is the exclamation
3041 point (!) then the sense of the switch is reversed for that symbol.
3042 For example:
3043
3044 @smallexample
3045 -w -K !foo -K fo*
3046 @end smallexample
3047
3048 would cause strip to only keep symbols that start with the letters
3049 ``fo'', but to discard the symbol ``foo''.
3050
3051 @item -x
3052 @itemx --discard-all
3053 Remove non-global symbols.
3054
3055 @item -X
3056 @itemx --discard-locals
3057 Remove compiler-generated local symbols.
3058 (These usually start with @samp{L} or @samp{.}.)
3059
3060 @item --keep-file-symbols
3061 When stripping a file, perhaps with @option{--strip-debug} or
3062 @option{--strip-unneeded}, retain any symbols specifying source file names,
3063 which would otherwise get stripped.
3064
3065 @item --only-keep-debug
3066 Strip a file, removing contents of any sections that would not be
3067 stripped by @option{--strip-debug} and leaving the debugging sections
3068 intact. In ELF files, this preserves all note sections in the output.
3069
3070 The intention is that this option will be used in conjunction with
3071 @option{--add-gnu-debuglink} to create a two part executable. One a
3072 stripped binary which will occupy less space in RAM and in a
3073 distribution and the second a debugging information file which is only
3074 needed if debugging abilities are required. The suggested procedure
3075 to create these files is as follows:
3076
3077 @enumerate
3078 @item Link the executable as normal. Assuming that is is called
3079 @code{foo} then...
3080 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
3081 create a file containing the debugging info.
3082 @item Run @code{objcopy --strip-debug foo} to create a
3083 stripped executable.
3084 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
3085 to add a link to the debugging info into the stripped executable.
3086 @end enumerate
3087
3088 Note---the choice of @code{.dbg} as an extension for the debug info
3089 file is arbitrary. Also the @code{--only-keep-debug} step is
3090 optional. You could instead do this:
3091
3092 @enumerate
3093 @item Link the executable as normal.
3094 @item Copy @code{foo} to @code{foo.full}
3095 @item Run @code{strip --strip-debug foo}
3096 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
3097 @end enumerate
3098
3099 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
3100 full executable. It does not have to be a file created by the
3101 @option{--only-keep-debug} switch.
3102
3103 Note---this switch is only intended for use on fully linked files. It
3104 does not make sense to use it on object files where the debugging
3105 information may be incomplete. Besides the gnu_debuglink feature
3106 currently only supports the presence of one filename containing
3107 debugging information, not multiple filenames on a one-per-object-file
3108 basis.
3109
3110 @item -V
3111 @itemx --version
3112 Show the version number for @command{strip}.
3113
3114 @item -v
3115 @itemx --verbose
3116 Verbose output: list all object files modified. In the case of
3117 archives, @samp{strip -v} lists all members of the archive.
3118 @end table
3119
3120 @c man end
3121
3122 @ignore
3123 @c man begin SEEALSO strip
3124 the Info entries for @file{binutils}.
3125 @c man end
3126 @end ignore
3127
3128 @node c++filt, addr2line, strip, Top
3129 @chapter c++filt
3130
3131 @kindex c++filt
3132 @cindex demangling C++ symbols
3133
3134 @c man title cxxfilt Demangle C++ and Java symbols.
3135
3136 @smallexample
3137 @c man begin SYNOPSIS cxxfilt
3138 c++filt [@option{-_}|@option{--strip-underscore}]
3139 [@option{-n}|@option{--no-strip-underscore}]
3140 [@option{-p}|@option{--no-params}]
3141 [@option{-t}|@option{--types}]
3142 [@option{-i}|@option{--no-verbose}]
3143 [@option{-s} @var{format}|@option{--format=}@var{format}]
3144 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
3145 @c man end
3146 @end smallexample
3147
3148 @c man begin DESCRIPTION cxxfilt
3149
3150 @kindex cxxfilt
3151 The C++ and Java languages provide function overloading, which means
3152 that you can write many functions with the same name, providing that
3153 each function takes parameters of different types. In order to be
3154 able to distinguish these similarly named functions C++ and Java
3155 encode them into a low-level assembler name which uniquely identifies
3156 each different version. This process is known as @dfn{mangling}. The
3157 @command{c++filt}
3158 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
3159 MS-DOS this program is named @command{CXXFILT}.}
3160 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
3161 names into user-level names so that they can be read.
3162
3163 Every alphanumeric word (consisting of letters, digits, underscores,
3164 dollars, or periods) seen in the input is a potential mangled name.
3165 If the name decodes into a C++ name, the C++ name replaces the
3166 low-level name in the output, otherwise the original word is output.
3167 In this way you can pass an entire assembler source file, containing
3168 mangled names, through @command{c++filt} and see the same source file
3169 containing demangled names.
3170
3171 You can also use @command{c++filt} to decipher individual symbols by
3172 passing them on the command line:
3173
3174 @example
3175 c++filt @var{symbol}
3176 @end example
3177
3178 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
3179 names from the standard input instead. All the results are printed on
3180 the standard output. The difference between reading names from the
3181 command line versus reading names from the standard input is that
3182 command line arguments are expected to be just mangled names and no
3183 checking is performed to separate them from surrounding text. Thus
3184 for example:
3185
3186 @smallexample
3187 c++filt -n _Z1fv
3188 @end smallexample
3189
3190 will work and demangle the name to ``f()'' whereas:
3191
3192 @smallexample
3193 c++filt -n _Z1fv,
3194 @end smallexample
3195
3196 will not work. (Note the extra comma at the end of the mangled
3197 name which makes it invalid). This command however will work:
3198
3199 @smallexample
3200 echo _Z1fv, | c++filt -n
3201 @end smallexample
3202
3203 and will display ``f(),'', i.e., the demangled name followed by a
3204 trailing comma. This behaviour is because when the names are read
3205 from the standard input it is expected that they might be part of an
3206 assembler source file where there might be extra, extraneous
3207 characters trailing after a mangled name. For example:
3208
3209 @smallexample
3210 .type _Z1fv, @@function
3211 @end smallexample
3212
3213 @c man end
3214
3215 @c man begin OPTIONS cxxfilt
3216
3217 @table @env
3218 @item -_
3219 @itemx --strip-underscore
3220 On some systems, both the C and C++ compilers put an underscore in front
3221 of every name. For example, the C name @code{foo} gets the low-level
3222 name @code{_foo}. This option removes the initial underscore. Whether
3223 @command{c++filt} removes the underscore by default is target dependent.
3224
3225 @item -n
3226 @itemx --no-strip-underscore
3227 Do not remove the initial underscore.
3228
3229 @item -p
3230 @itemx --no-params
3231 When demangling the name of a function, do not display the types of
3232 the function's parameters.
3233
3234 @item -t
3235 @itemx --types
3236 Attempt to demangle types as well as function names. This is disabled
3237 by default since mangled types are normally only used internally in
3238 the compiler, and they can be confused with non-mangled names. For example,
3239 a function called ``a'' treated as a mangled type name would be
3240 demangled to ``signed char''.
3241
3242 @item -i
3243 @itemx --no-verbose
3244 Do not include implementation details (if any) in the demangled
3245 output.
3246
3247 @item -s @var{format}
3248 @itemx --format=@var{format}
3249 @command{c++filt} can decode various methods of mangling, used by
3250 different compilers. The argument to this option selects which
3251 method it uses:
3252
3253 @table @code
3254 @item auto
3255 Automatic selection based on executable (the default method)
3256 @item gnu
3257 the one used by the @sc{gnu} C++ compiler (g++)
3258 @item lucid
3259 the one used by the Lucid compiler (lcc)
3260 @item arm
3261 the one specified by the C++ Annotated Reference Manual
3262 @item hp
3263 the one used by the HP compiler (aCC)
3264 @item edg
3265 the one used by the EDG compiler
3266 @item gnu-v3
3267 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
3268 @item java
3269 the one used by the @sc{gnu} Java compiler (gcj)
3270 @item gnat
3271 the one used by the @sc{gnu} Ada compiler (GNAT).
3272 @end table
3273
3274 @item --help
3275 Print a summary of the options to @command{c++filt} and exit.
3276
3277 @item --version
3278 Print the version number of @command{c++filt} and exit.
3279 @end table
3280
3281 @c man end
3282
3283 @ignore
3284 @c man begin SEEALSO cxxfilt
3285 the Info entries for @file{binutils}.
3286 @c man end
3287 @end ignore
3288
3289 @quotation
3290 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
3291 user interface are subject to change in future releases. In particular,
3292 a command-line option may be required in the future to decode a name
3293 passed as an argument on the command line; in other words,
3294
3295 @example
3296 c++filt @var{symbol}
3297 @end example
3298
3299 @noindent
3300 may in a future release become
3301
3302 @example
3303 c++filt @var{option} @var{symbol}
3304 @end example
3305 @end quotation
3306
3307 @node addr2line
3308 @chapter addr2line
3309
3310 @kindex addr2line
3311 @cindex address to file name and line number
3312
3313 @c man title addr2line convert addresses into file names and line numbers.
3314
3315 @smallexample
3316 @c man begin SYNOPSIS addr2line
3317 addr2line [@option{-a}|@option{--addresses}]
3318 [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
3319 [@option{-C}|@option{--demangle}[=@var{style}]]
3320 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
3321 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
3322 [@option{-i}|@option{--inlines}]
3323 [@option{-p}|@option{--pretty-print}]
3324 [@option{-j}|@option{--section=}@var{name}]
3325 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
3326 [addr addr @dots{}]
3327 @c man end
3328 @end smallexample
3329
3330 @c man begin DESCRIPTION addr2line
3331
3332 @command{addr2line} translates addresses into file names and line numbers.
3333 Given an address in an executable or an offset in a section of a relocatable
3334 object, it uses the debugging information to figure out which file name and
3335 line number are associated with it.
3336
3337 The executable or relocatable object to use is specified with the @option{-e}
3338 option. The default is the file @file{a.out}. The section in the relocatable
3339 object to use is specified with the @option{-j} option.
3340
3341 @command{addr2line} has two modes of operation.
3342
3343 In the first, hexadecimal addresses are specified on the command line,
3344 and @command{addr2line} displays the file name and line number for each
3345 address.
3346
3347 In the second, @command{addr2line} reads hexadecimal addresses from
3348 standard input, and prints the file name and line number for each
3349 address on standard output. In this mode, @command{addr2line} may be used
3350 in a pipe to convert dynamically chosen addresses.
3351
3352 The format of the output is @samp{FILENAME:LINENO}. By default
3353 each input address generates one line of output.
3354
3355 Two options can generate additional lines before each
3356 @samp{FILENAME:LINENO} line (in that order).
3357
3358 If the @option{-a} option is used then a line with the input address
3359 is displayed.
3360
3361 If the @option{-f} option is used, then a line with the
3362 @samp{FUNCTIONNAME} is displayed. This is the name of the function
3363 containing the address.
3364
3365 One option can generate additional lines after the
3366 @samp{FILENAME:LINENO} line.
3367
3368 If the @option{-i} option is used and the code at the given address is
3369 present there because of inlining by the compiler then additional
3370 lines are displayed afterwards. One or two extra lines (if the
3371 @option{-f} option is used) are displayed for each inlined function.
3372
3373 Alternatively if the @option{-p} option is used then each input
3374 address generates a single, long, output line containing the address,
3375 the function name, the file name and the line number. If the
3376 @option{-i} option has also been used then any inlined functions will
3377 be displayed in the same manner, but on separate lines, and prefixed
3378 by the text @samp{(inlined by)}.
3379
3380 If the file name or function name can not be determined,
3381 @command{addr2line} will print two question marks in their place. If the
3382 line number can not be determined, @command{addr2line} will print 0.
3383
3384 @c man end
3385
3386 @c man begin OPTIONS addr2line
3387
3388 The long and short forms of options, shown here as alternatives, are
3389 equivalent.
3390
3391 @table @env
3392 @item -a
3393 @itemx --addresses
3394 Display the address before the function name, file and line number
3395 information. The address is printed with a @samp{0x} prefix to easily
3396 identify it.
3397
3398 @item -b @var{bfdname}
3399 @itemx --target=@var{bfdname}
3400 @cindex object code format
3401 Specify that the object-code format for the object files is
3402 @var{bfdname}.
3403
3404 @item -C
3405 @itemx --demangle[=@var{style}]
3406 @cindex demangling in objdump
3407 Decode (@dfn{demangle}) low-level symbol names into user-level names.
3408 Besides removing any initial underscore prepended by the system, this
3409 makes C++ function names readable. Different compilers have different
3410 mangling styles. The optional demangling style argument can be used to
3411 choose an appropriate demangling style for your compiler. @xref{c++filt},
3412 for more information on demangling.
3413
3414 @item -e @var{filename}
3415 @itemx --exe=@var{filename}
3416 Specify the name of the executable for which addresses should be
3417 translated. The default file is @file{a.out}.
3418
3419 @item -f
3420 @itemx --functions
3421 Display function names as well as file and line number information.
3422
3423 @item -s
3424 @itemx --basenames
3425 Display only the base of each file name.
3426
3427 @item -i
3428 @itemx --inlines
3429 If the address belongs to a function that was inlined, the source
3430 information for all enclosing scopes back to the first non-inlined
3431 function will also be printed. For example, if @code{main} inlines
3432 @code{callee1} which inlines @code{callee2}, and address is from
3433 @code{callee2}, the source information for @code{callee1} and @code{main}
3434 will also be printed.
3435
3436 @item -j
3437 @itemx --section
3438 Read offsets relative to the specified section instead of absolute addresses.
3439
3440 @item -p
3441 @itemx --pretty-print
3442 Make the output more human friendly: each location are printed on one line.
3443 If option @option{-i} is specified, lines for all enclosing scopes are
3444 prefixed with @samp{(inlined by)}.
3445 @end table
3446
3447 @c man end
3448
3449 @ignore
3450 @c man begin SEEALSO addr2line
3451 Info entries for @file{binutils}.
3452 @c man end
3453 @end ignore
3454
3455 @node nlmconv
3456 @chapter nlmconv
3457
3458 @command{nlmconv} converts a relocatable object file into a NetWare
3459 Loadable Module.
3460
3461 @ignore
3462 @command{nlmconv} currently works with @samp{i386} object
3463 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
3464 object files in @sc{elf}, or @code{a.out} format@footnote{
3465 @command{nlmconv} should work with any @samp{i386} or @sc{sparc} object
3466 format in the Binary File Descriptor library. It has only been tested
3467 with the above formats.}.
3468 @end ignore
3469
3470 @quotation
3471 @emph{Warning:} @command{nlmconv} is not always built as part of the binary
3472 utilities, since it is only useful for NLM targets.
3473 @end quotation
3474
3475 @c man title nlmconv converts object code into an NLM.
3476
3477 @smallexample
3478 @c man begin SYNOPSIS nlmconv
3479 nlmconv [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
3480 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
3481 [@option{-T} @var{headerfile}|@option{--header-file=}@var{headerfile}]
3482 [@option{-d}|@option{--debug}] [@option{-l} @var{linker}|@option{--linker=}@var{linker}]
3483 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
3484 @var{infile} @var{outfile}
3485 @c man end
3486 @end smallexample
3487
3488 @c man begin DESCRIPTION nlmconv
3489
3490 @command{nlmconv} converts the relocatable @samp{i386} object file
3491 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
3492 reading @var{headerfile} for NLM header information. For instructions
3493 on writing the NLM command file language used in header files, see the
3494 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
3495 Development and Tools Overview}, which is part of the NLM Software
3496 Developer's Kit (``NLM SDK''), available from Novell, Inc.
3497 @command{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
3498 @var{infile};
3499 @ifclear man
3500 see @ref{BFD,,BFD,ld.info,Using LD}, for more information.
3501 @end ifclear
3502
3503 @command{nlmconv} can perform a link step. In other words, you can list
3504 more than one object file for input if you list them in the definitions
3505 file (rather than simply specifying one input file on the command line).
3506 In this case, @command{nlmconv} calls the linker for you.
3507
3508 @c man end
3509
3510 @c man begin OPTIONS nlmconv
3511
3512 @table @env
3513 @item -I @var{bfdname}
3514 @itemx --input-target=@var{bfdname}
3515 Object format of the input file. @command{nlmconv} can usually determine
3516 the format of a given file (so no default is necessary).
3517 @xref{Target Selection}, for more information.
3518
3519 @item -O @var{bfdname}
3520 @itemx --output-target=@var{bfdname}
3521 Object format of the output file. @command{nlmconv} infers the output
3522 format based on the input format, e.g. for a @samp{i386} input file the
3523 output format is @samp{nlm32-i386}.
3524 @xref{Target Selection}, for more information.
3525
3526 @item -T @var{headerfile}
3527 @itemx --header-file=@var{headerfile}
3528 Reads @var{headerfile} for NLM header information. For instructions on
3529 writing the NLM command file language used in header files, see@ see the
3530 @samp{linkers} section, of the @cite{NLM Development and Tools
3531 Overview}, which is part of the NLM Software Developer's Kit, available
3532 from Novell, Inc.
3533
3534 @item -d
3535 @itemx --debug
3536 Displays (on standard error) the linker command line used by @command{nlmconv}.
3537
3538 @item -l @var{linker}
3539 @itemx --linker=@var{linker}
3540 Use @var{linker} for any linking. @var{linker} can be an absolute or a
3541 relative pathname.
3542
3543 @item -h
3544 @itemx --help
3545 Prints a usage summary.
3546
3547 @item -V
3548 @itemx --version
3549 Prints the version number for @command{nlmconv}.
3550 @end table
3551
3552 @c man end
3553
3554 @ignore
3555 @c man begin SEEALSO nlmconv
3556 the Info entries for @file{binutils}.
3557 @c man end
3558 @end ignore
3559
3560 @node windmc
3561 @chapter windmc
3562
3563 @command{windmc} may be used to generator Windows message resources.
3564
3565 @quotation
3566 @emph{Warning:} @command{windmc} is not always built as part of the binary
3567 utilities, since it is only useful for Windows targets.
3568 @end quotation
3569
3570 @c man title windmc generates Windows message resources.
3571
3572 @smallexample
3573 @c man begin SYNOPSIS windmc
3574 windmc [options] input-file
3575 @c man end
3576 @end smallexample
3577
3578 @c man begin DESCRIPTION windmc
3579
3580 @command{windmc} reads message definitions from an input file (.mc) and
3581 translate them into a set of output files. The output files may be of
3582 four kinds:
3583
3584 @table @code
3585 @item h
3586 A C header file containing the message definitions.
3587
3588 @item rc
3589 A resource file compilable by the @command{windres} tool.
3590
3591 @item bin
3592 One or more binary files containing the resource data for a specific
3593 message language.
3594
3595 @item dbg
3596 A C include file that maps message id's to their symbolic name.
3597 @end table
3598
3599 The exact description of these different formats is available in
3600 documentation from Microsoft.
3601
3602 When @command{windmc} converts from the @code{mc} format to the @code{bin}
3603 format, @code{rc}, @code{h}, and optional @code{dbg} it is acting like the
3604 Windows Message Compiler.
3605
3606 @c man end
3607
3608 @c man begin OPTIONS windmc
3609
3610 @table @env
3611 @item -a
3612 @itemx --ascii_in
3613 Specifies that the input file specified is ASCII. This is the default
3614 behaviour.
3615
3616 @item -A
3617 @itemx --ascii_out
3618 Specifies that messages in the output @code{bin} files should be in ASCII
3619 format.
3620
3621 @item -b
3622 @itemx --binprefix
3623 Specifies that @code{bin} filenames should have to be prefixed by the
3624 basename of the source file.
3625
3626 @item -c
3627 @itemx --customflag
3628 Sets the customer bit in all message id's.
3629
3630 @item -C @var{codepage}
3631 @itemx --codepage_in @var{codepage}
3632 Sets the default codepage to be used to convert input file to UTF16. The
3633 default is ocdepage 1252.
3634
3635 @item -d
3636 @itemx --decimal_values
3637 Outputs the constants in the header file in decimal. Default is using
3638 hexadecimal output.
3639
3640 @item -e @var{ext}
3641 @itemx --extension @var{ext}
3642 The extension for the header file. The default is .h extension.
3643
3644 @item -F @var{target}
3645 @itemx --target @var{target}
3646 Specify the BFD format to use for a bin file as output. This
3647 is a BFD target name; you can use the @option{--help} option to see a list
3648 of supported targets. Normally @command{windmc} will use the default
3649 format, which is the first one listed by the @option{--help} option.
3650 @ifclear man
3651 @ref{Target Selection}.
3652 @end ifclear
3653
3654 @item -h @var{path}
3655 @itemx --headerdir @var{path}
3656 The target directory of the generated header file. The default is the
3657 current directory.
3658
3659 @item -H
3660 @itemx --help
3661 Displays a list of command line options and then exits.
3662
3663 @item -m @var{characters}
3664 @itemx --maxlength @var{characters}
3665 Instructs @command{windmc} to generate a warning if the length
3666 of any message exceeds the number specified.
3667
3668 @item -n
3669 @itemx --nullterminate
3670 Terminate message text in @code{bin} files by zero. By default they are
3671 terminated by CR/LF.
3672
3673 @item -o
3674 @itemx --hresult_use
3675 Not yet implemented. Instructs @code{windmc} to generate an OLE2 header
3676 file, using HRESULT definitions. Status codes are used if the flag is not
3677 specified.
3678
3679 @item -O @var{codepage}
3680 @itemx --codepage_out @var{codepage}
3681 Sets the default codepage to be used to output text files. The default
3682 is ocdepage 1252.
3683
3684 @item -r @var{path}
3685 @itemx --rcdir @var{path}
3686 The target directory for the generated @code{rc} script and the generated
3687 @code{bin} files that the resource compiler script includes. The default
3688 is the current directory.
3689
3690 @item -u
3691 @itemx --unicode_in
3692 Specifies that the input file is UTF16.
3693
3694 @item -U
3695 @itemx --unicode_out
3696 Specifies that messages in the output @code{bin} file should be in UTF16
3697 format. This is the default behaviour.
3698
3699 @item -v
3700 @item --verbose
3701 Enable verbose mode.
3702
3703 @item -V
3704 @item --version
3705 Prints the version number for @command{windmc}.
3706
3707 @item -x @var{path}
3708 @itemx --xdgb @var{path}
3709 The path of the @code{dbg} C include file that maps message id's to the
3710 symbolic name. No such file is generated without specifying the switch.
3711 @end table
3712
3713 @c man end
3714
3715 @ignore
3716 @c man begin SEEALSO windmc
3717 the Info entries for @file{binutils}.
3718 @c man end
3719 @end ignore
3720
3721 @node windres
3722 @chapter windres
3723
3724 @command{windres} may be used to manipulate Windows resources.
3725
3726 @quotation
3727 @emph{Warning:} @command{windres} is not always built as part of the binary
3728 utilities, since it is only useful for Windows targets.
3729 @end quotation
3730
3731 @c man title windres manipulate Windows resources.
3732
3733 @smallexample
3734 @c man begin SYNOPSIS windres
3735 windres [options] [input-file] [output-file]
3736 @c man end
3737 @end smallexample
3738
3739 @c man begin DESCRIPTION windres
3740
3741 @command{windres} reads resources from an input file and copies them into
3742 an output file. Either file may be in one of three formats:
3743
3744 @table @code
3745 @item rc
3746 A text format read by the Resource Compiler.
3747
3748 @item res
3749 A binary format generated by the Resource Compiler.
3750
3751 @item coff
3752 A COFF object or executable.
3753 @end table
3754
3755 The exact description of these different formats is available in
3756 documentation from Microsoft.
3757
3758 When @command{windres} converts from the @code{rc} format to the @code{res}
3759 format, it is acting like the Windows Resource Compiler. When
3760 @command{windres} converts from the @code{res} format to the @code{coff}
3761 format, it is acting like the Windows @code{CVTRES} program.
3762
3763 When @command{windres} generates an @code{rc} file, the output is similar
3764 but not identical to the format expected for the input. When an input
3765 @code{rc} file refers to an external filename, an output @code{rc} file
3766 will instead include the file contents.
3767
3768 If the input or output format is not specified, @command{windres} will
3769 guess based on the file name, or, for the input file, the file contents.
3770 A file with an extension of @file{.rc} will be treated as an @code{rc}
3771 file, a file with an extension of @file{.res} will be treated as a
3772 @code{res} file, and a file with an extension of @file{.o} or
3773 @file{.exe} will be treated as a @code{coff} file.
3774
3775 If no output file is specified, @command{windres} will print the resources
3776 in @code{rc} format to standard output.
3777
3778 The normal use is for you to write an @code{rc} file, use @command{windres}
3779 to convert it to a COFF object file, and then link the COFF file into
3780 your application. This will make the resources described in the
3781 @code{rc} file available to Windows.
3782
3783 @c man end
3784
3785 @c man begin OPTIONS windres
3786
3787 @table @env
3788 @item -i @var{filename}
3789 @itemx --input @var{filename}
3790 The name of the input file. If this option is not used, then
3791 @command{windres} will use the first non-option argument as the input file
3792 name. If there are no non-option arguments, then @command{windres} will
3793 read from standard input. @command{windres} can not read a COFF file from
3794 standard input.
3795
3796 @item -o @var{filename}
3797 @itemx --output @var{filename}
3798 The name of the output file. If this option is not used, then
3799 @command{windres} will use the first non-option argument, after any used
3800 for the input file name, as the output file name. If there is no
3801 non-option argument, then @command{windres} will write to standard output.
3802 @command{windres} can not write a COFF file to standard output. Note,
3803 for compatibility with @command{rc} the option @option{-fo} is also
3804 accepted, but its use is not recommended.
3805
3806 @item -J @var{format}
3807 @itemx --input-format @var{format}
3808 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
3809 @samp{coff}. If no input format is specified, @command{windres} will
3810 guess, as described above.
3811
3812 @item -O @var{format}
3813 @itemx --output-format @var{format}
3814 The output format to generate. @var{format} may be @samp{res},
3815 @samp{rc}, or @samp{coff}. If no output format is specified,
3816 @command{windres} will guess, as described above.
3817
3818 @item -F @var{target}
3819 @itemx --target @var{target}
3820 Specify the BFD format to use for a COFF file as input or output. This
3821 is a BFD target name; you can use the @option{--help} option to see a list
3822 of supported targets. Normally @command{windres} will use the default
3823 format, which is the first one listed by the @option{--help} option.
3824 @ifclear man
3825 @ref{Target Selection}.
3826 @end ifclear
3827
3828 @item --preprocessor @var{program}
3829 When @command{windres} reads an @code{rc} file, it runs it through the C
3830 preprocessor first. This option may be used to specify the preprocessor
3831 to use, including any leading arguments. The default preprocessor
3832 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
3833
3834 @item --preprocessor-arg @var{option}
3835 When @command{windres} reads an @code{rc} file, it runs it through
3836 the C preprocessor first. This option may be used to specify additional
3837 text to be passed to preprocessor on its command line.
3838 This option can be used multiple times to add multiple options to the
3839 preprocessor command line.
3840
3841 @item -I @var{directory}
3842 @itemx --include-dir @var{directory}
3843 Specify an include directory to use when reading an @code{rc} file.
3844 @command{windres} will pass this to the preprocessor as an @option{-I}
3845 option. @command{windres} will also search this directory when looking for
3846 files named in the @code{rc} file. If the argument passed to this command
3847 matches any of the supported @var{formats} (as described in the @option{-J}
3848 option), it will issue a deprecation warning, and behave just like the
3849 @option{-J} option. New programs should not use this behaviour. If a
3850 directory happens to match a @var{format}, simple prefix it with @samp{./}
3851 to disable the backward compatibility.
3852
3853 @item -D @var{target}
3854 @itemx --define @var{sym}[=@var{val}]
3855 Specify a @option{-D} option to pass to the preprocessor when reading an
3856 @code{rc} file.
3857
3858 @item -U @var{target}
3859 @itemx --undefine @var{sym}
3860 Specify a @option{-U} option to pass to the preprocessor when reading an
3861 @code{rc} file.
3862
3863 @item -r
3864 Ignored for compatibility with rc.
3865
3866 @item -v
3867 Enable verbose mode. This tells you what the preprocessor is if you
3868 didn't specify one.
3869
3870 @item -c @var{val}
3871 @item --codepage @var{val}
3872 Specify the default codepage to use when reading an @code{rc} file.
3873 @var{val} should be a hexadecimal prefixed by @samp{0x} or decimal
3874 codepage code. The valid range is from zero up to 0xffff, but the
3875 validity of the codepage is host and configuration dependent.
3876
3877 @item -l @var{val}
3878 @item --language @var{val}
3879 Specify the default language to use when reading an @code{rc} file.
3880 @var{val} should be a hexadecimal language code. The low eight bits are
3881 the language, and the high eight bits are the sublanguage.
3882
3883 @item --use-temp-file
3884 Use a temporary file to instead of using popen to read the output of
3885 the preprocessor. Use this option if the popen implementation is buggy
3886 on the host (eg., certain non-English language versions of Windows 95 and
3887 Windows 98 are known to have buggy popen where the output will instead
3888 go the console).
3889
3890 @item --no-use-temp-file
3891 Use popen, not a temporary file, to read the output of the preprocessor.
3892 This is the default behaviour.
3893
3894 @item -h
3895 @item --help
3896 Prints a usage summary.
3897
3898 @item -V
3899 @item --version
3900 Prints the version number for @command{windres}.
3901
3902 @item --yydebug
3903 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
3904 this will turn on parser debugging.
3905 @end table
3906
3907 @c man end
3908
3909 @ignore
3910 @c man begin SEEALSO windres
3911 the Info entries for @file{binutils}.
3912 @c man end
3913 @end ignore
3914
3915 @node dlltool
3916 @chapter dlltool
3917 @cindex DLL
3918 @kindex dlltool
3919
3920 @command{dlltool} is used to create the files needed to create dynamic
3921 link libraries (DLLs) on systems which understand PE format image
3922 files such as Windows. A DLL contains an export table which contains
3923 information that the runtime loader needs to resolve references from a
3924 referencing program.
3925
3926 The export table is generated by this program by reading in a
3927 @file{.def} file or scanning the @file{.a} and @file{.o} files which
3928 will be in the DLL. A @file{.o} file can contain information in
3929 special @samp{.drectve} sections with export information.
3930
3931 @quotation
3932 @emph{Note:} @command{dlltool} is not always built as part of the
3933 binary utilities, since it is only useful for those targets which
3934 support DLLs.
3935 @end quotation
3936
3937 @c man title dlltool Create files needed to build and use DLLs.
3938
3939 @smallexample
3940 @c man begin SYNOPSIS dlltool
3941 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
3942 [@option{-b}|@option{--base-file} @var{base-file-name}]
3943 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
3944 [@option{-z}|@option{--output-def} @var{def-file-name}]
3945 [@option{-l}|@option{--output-lib} @var{library-file-name}]
3946 [@option{-y}|@option{--output-delaylib} @var{library-file-name}]
3947 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
3948 [@option{--exclude-symbols} @var{list}]
3949 [@option{--no-default-excludes}]
3950 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
3951 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
3952 [@option{-a}|@option{--add-indirect}]
3953 [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}]
3954 [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}]
3955 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
3956 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}]
3957 [@option{--use-nul-prefixed-import-tables}]
3958 [@option{-I}|@option{--identify} @var{library-file-name}] [@option{--identify-strict}]
3959 [@option{-i}|@option{--interwork}]
3960 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
3961 [@option{-v}|@option{--verbose}]
3962 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
3963 [@option{--no-leading-underscore}] [@option{--leading-underscore}]
3964 [object-file @dots{}]
3965 @c man end
3966 @end smallexample
3967
3968 @c man begin DESCRIPTION dlltool
3969
3970 @command{dlltool} reads its inputs, which can come from the @option{-d} and
3971 @option{-b} options as well as object files specified on the command
3972 line. It then processes these inputs and if the @option{-e} option has
3973 been specified it creates a exports file. If the @option{-l} option
3974 has been specified it creates a library file and if the @option{-z} option
3975 has been specified it creates a def file. Any or all of the @option{-e},
3976 @option{-l} and @option{-z} options can be present in one invocation of
3977 dlltool.
3978
3979 When creating a DLL, along with the source for the DLL, it is necessary
3980 to have three other files. @command{dlltool} can help with the creation of
3981 these files.
3982
3983 The first file is a @file{.def} file which specifies which functions are
3984 exported from the DLL, which functions the DLL imports, and so on. This
3985 is a text file and can be created by hand, or @command{dlltool} can be used
3986 to create it using the @option{-z} option. In this case @command{dlltool}
3987 will scan the object files specified on its command line looking for
3988 those functions which have been specially marked as being exported and
3989 put entries for them in the @file{.def} file it creates.
3990
3991 In order to mark a function as being exported from a DLL, it needs to
3992 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
3993 section of the object file. This can be done in C by using the
3994 asm() operator:
3995
3996 @smallexample
3997 asm (".section .drectve");
3998 asm (".ascii \"-export:my_func\"");
3999
4000 int my_func (void) @{ @dots{} @}
4001 @end smallexample
4002
4003 The second file needed for DLL creation is an exports file. This file
4004 is linked with the object files that make up the body of the DLL and it
4005 handles the interface between the DLL and the outside world. This is a
4006 binary file and it can be created by giving the @option{-e} option to
4007 @command{dlltool} when it is creating or reading in a @file{.def} file.
4008
4009 The third file needed for DLL creation is the library file that programs
4010 will link with in order to access the functions in the DLL (an `import
4011 library'). This file can be created by giving the @option{-l} option to
4012 dlltool when it is creating or reading in a @file{.def} file.
4013
4014 If the @option{-y} option is specified, dlltool generates a delay-import
4015 library that can be used instead of the normal import library to allow
4016 a program to link to the dll only as soon as an imported function is
4017 called for the first time. The resulting executable will need to be
4018 linked to the static delayimp library containing __delayLoadHelper2(),
4019 which in turn will import LoadLibraryA and GetProcAddress from kernel32.
4020
4021 @command{dlltool} builds the library file by hand, but it builds the
4022 exports file by creating temporary files containing assembler statements
4023 and then assembling these. The @option{-S} command line option can be
4024 used to specify the path to the assembler that dlltool will use,
4025 and the @option{-f} option can be used to pass specific flags to that
4026 assembler. The @option{-n} can be used to prevent dlltool from deleting
4027 these temporary assembler files when it is done, and if @option{-n} is
4028 specified twice then this will prevent dlltool from deleting the
4029 temporary object files it used to build the library.
4030
4031 Here is an example of creating a DLL from a source file @samp{dll.c} and
4032 also creating a program (from an object file called @samp{program.o})
4033 that uses that DLL:
4034
4035 @smallexample
4036 gcc -c dll.c
4037 dlltool -e exports.o -l dll.lib dll.o
4038 gcc dll.o exports.o -o dll.dll
4039 gcc program.o dll.lib -o program
4040 @end smallexample
4041
4042
4043 @command{dlltool} may also be used to query an existing import library
4044 to determine the name of the DLL to which it is associated. See the
4045 description of the @option{-I} or @option{--identify} option.
4046
4047 @c man end
4048
4049 @c man begin OPTIONS dlltool
4050
4051 The command line options have the following meanings:
4052
4053 @table @env
4054
4055 @item -d @var{filename}
4056 @itemx --input-def @var{filename}
4057 @cindex input .def file
4058 Specifies the name of a @file{.def} file to be read in and processed.
4059
4060 @item -b @var{filename}
4061 @itemx --base-file @var{filename}
4062 @cindex base files
4063 Specifies the name of a base file to be read in and processed. The
4064 contents of this file will be added to the relocation section in the
4065 exports file generated by dlltool.
4066
4067 @item -e @var{filename}
4068 @itemx --output-exp @var{filename}
4069 Specifies the name of the export file to be created by dlltool.
4070
4071 @item -z @var{filename}
4072 @itemx --output-def @var{filename}
4073 Specifies the name of the @file{.def} file to be created by dlltool.
4074
4075 @item -l @var{filename}
4076 @itemx --output-lib @var{filename}
4077 Specifies the name of the library file to be created by dlltool.
4078
4079 @item -y @var{filename}
4080 @itemx --output-delaylib @var{filename}
4081 Specifies the name of the delay-import library file to be created by dlltool.
4082
4083 @item --export-all-symbols
4084 Treat all global and weak defined symbols found in the input object
4085 files as symbols to be exported. There is a small list of symbols which
4086 are not exported by default; see the @option{--no-default-excludes}
4087 option. You may add to the list of symbols to not export by using the
4088 @option{--exclude-symbols} option.
4089
4090 @item --no-export-all-symbols
4091 Only export symbols explicitly listed in an input @file{.def} file or in
4092 @samp{.drectve} sections in the input object files. This is the default
4093 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
4094 attributes in the source code.
4095
4096 @item --exclude-symbols @var{list}
4097 Do not export the symbols in @var{list}. This is a list of symbol names
4098 separated by comma or colon characters. The symbol names should not
4099 contain a leading underscore. This is only meaningful when
4100 @option{--export-all-symbols} is used.
4101
4102 @item --no-default-excludes
4103 When @option{--export-all-symbols} is used, it will by default avoid
4104 exporting certain special symbols. The current list of symbols to avoid
4105 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
4106 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
4107 to go ahead and export these special symbols. This is only meaningful
4108 when @option{--export-all-symbols} is used.
4109
4110 @item -S @var{path}
4111 @itemx --as @var{path}
4112 Specifies the path, including the filename, of the assembler to be used
4113 to create the exports file.
4114
4115 @item -f @var{options}
4116 @itemx --as-flags @var{options}
4117 Specifies any specific command line options to be passed to the
4118 assembler when building the exports file. This option will work even if
4119 the @option{-S} option is not used. This option only takes one argument,
4120 and if it occurs more than once on the command line, then later
4121 occurrences will override earlier occurrences. So if it is necessary to
4122 pass multiple options to the assembler they should be enclosed in
4123 double quotes.
4124
4125 @item -D @var{name}
4126 @itemx --dll-name @var{name}
4127 Specifies the name to be stored in the @file{.def} file as the name of
4128 the DLL when the @option{-e} option is used. If this option is not
4129 present, then the filename given to the @option{-e} option will be
4130 used as the name of the DLL.
4131
4132 @item -m @var{machine}
4133 @itemx -machine @var{machine}
4134 Specifies the type of machine for which the library file should be
4135 built. @command{dlltool} has a built in default type, depending upon how
4136 it was created, but this option can be used to override that. This is
4137 normally only useful when creating DLLs for an ARM processor, when the
4138 contents of the DLL are actually encode using Thumb instructions.
4139
4140 @item -a
4141 @itemx --add-indirect
4142 Specifies that when @command{dlltool} is creating the exports file it
4143 should add a section which allows the exported functions to be
4144 referenced without using the import library. Whatever the hell that
4145 means!
4146
4147 @item -U
4148 @itemx --add-underscore
4149 Specifies that when @command{dlltool} is creating the exports file it
4150 should prepend an underscore to the names of @emph{all} exported symbols.
4151
4152 @item --no-leading-underscore
4153 @item --leading-underscore
4154 Specifies whether standard symbol should be forced to be prefixed, or
4155 not.
4156
4157 @item --add-stdcall-underscore
4158 Specifies that when @command{dlltool} is creating the exports file it
4159 should prepend an underscore to the names of exported @emph{stdcall}
4160 functions. Variable names and non-stdcall function names are not modified.
4161 This option is useful when creating GNU-compatible import libs for third
4162 party DLLs that were built with MS-Windows tools.
4163
4164 @item -k
4165 @itemx --kill-at
4166 Specifies that @samp{@@<number>} suffixes should be omitted from the names
4167 of stdcall functions that will be imported from the DLL. This is
4168 useful when creating an import library for a DLL which exports stdcall
4169 functions but without the usual @samp{@@<number>} symbol name suffix.
4170
4171 This does not change the naming of symbols provided by the import library
4172 to programs linked against it, but only the entries in the import table
4173 (ie the .idata section).
4174
4175 @item -A
4176 @itemx --add-stdcall-alias
4177 Specifies that when @command{dlltool} is creating the exports file it
4178 should add aliases for stdcall symbols without @samp{@@ <number>}
4179 in addition to the symbols with @samp{@@ <number>}.
4180
4181 @item -p
4182 @itemx --ext-prefix-alias @var{prefix}
4183 Causes @command{dlltool} to create external aliases for all DLL
4184 imports with the specified prefix. The aliases are created for both
4185 external and import symbols with no leading underscore.
4186
4187 @item -x
4188 @itemx --no-idata4
4189 Specifies that when @command{dlltool} is creating the exports and library
4190 files it should omit the @code{.idata4} section. This is for compatibility
4191 with certain operating systems.
4192
4193 @item --use-nul-prefixed-import-tables
4194 Specifies that when @command{dlltool} is creating the exports and library
4195 files it should prefix the @code{.idata4} and @code{.idata5} by zero an
4196 element. This emulates old gnu import library generation of
4197 @code{dlltool}. By default this option is turned off.
4198
4199 @item -c
4200 @itemx --no-idata5
4201 Specifies that when @command{dlltool} is creating the exports and library
4202 files it should omit the @code{.idata5} section. This is for compatibility
4203 with certain operating systems.
4204
4205 @item -I @var{filename}
4206 @itemx --identify @var{filename}
4207 Specifies that @command{dlltool} should inspect the import library
4208 indicated by @var{filename} and report, on @code{stdout}, the name(s)
4209 of the associated DLL(s). This can be performed in addition to any
4210 other operations indicated by the other options and arguments.
4211 @command{dlltool} fails if the import library does not exist or is not
4212 actually an import library. See also @option{--identify-strict}.
4213
4214 @item --identify-strict
4215 Modifies the behavior of the @option{--identify} option, such
4216 that an error is reported if @var{filename} is associated with
4217 more than one DLL.
4218
4219 @item -i
4220 @itemx --interwork
4221 Specifies that @command{dlltool} should mark the objects in the library
4222 file and exports file that it produces as supporting interworking
4223 between ARM and Thumb code.
4224
4225 @item -n
4226 @itemx --nodelete
4227 Makes @command{dlltool} preserve the temporary assembler files it used to
4228 create the exports file. If this option is repeated then dlltool will
4229 also preserve the temporary object files it uses to create the library
4230 file.
4231
4232 @item -t @var{prefix}
4233 @itemx --temp-prefix @var{prefix}
4234 Makes @command{dlltool} use @var{prefix} when constructing the names of
4235 temporary assembler and object files. By default, the temp file prefix
4236 is generated from the pid.
4237
4238 @item -v
4239 @itemx --verbose
4240 Make dlltool describe what it is doing.
4241
4242 @item -h
4243 @itemx --help
4244 Displays a list of command line options and then exits.
4245
4246 @item -V
4247 @itemx --version
4248 Displays dlltool's version number and then exits.
4249
4250 @end table
4251
4252 @c man end
4253
4254 @menu
4255 * def file format:: The format of the dlltool @file{.def} file
4256 @end menu
4257
4258 @node def file format
4259 @section The format of the @command{dlltool} @file{.def} file
4260
4261 A @file{.def} file contains any number of the following commands:
4262
4263 @table @asis
4264
4265 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
4266 The result is going to be named @var{name}@code{.exe}.
4267
4268 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
4269 The result is going to be named @var{name}@code{.dll}.
4270 Note: If you want to use LIBRARY as name then you need to quote. Otherwise
4271 this will fail due a necessary hack for libtool (see PR binutils/13710 for more
4272 details).
4273
4274 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) ) [ == } @var{its_name} @code{]}
4275 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
4276 Declares @var{name1} as an exported symbol from the DLL, with optional
4277 ordinal number @var{integer}, or declares @var{name1} as an alias
4278 (forward) of the function @var{external-name} in the DLL.
4279 If @var{its_name} is specified, this name is used as string in export table.
4280 @var{module-name}.
4281 Note: The @code{EXPORTS} has to be the last command in .def file, as keywords
4282 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4283 If you want to use LIBRARY as name then you need to quote it.
4284
4285 @item @code{IMPORTS ( (} @var{internal-name} @code{=} @var{module-name} @code{.} @var{integer} @code{) | [} @var{internal-name} @code{= ]} @var{module-name} @code{.} @var{external-name} @code{) [ == ) @var{its_name} @code{]} *}
4286 Declares that @var{external-name} or the exported function whose
4287 ordinal number is @var{integer} is to be imported from the file
4288 @var{module-name}. If @var{internal-name} is specified then this is
4289 the name that the imported function will be referred to in the body of
4290 the DLL.
4291 If @var{its_name} is specified, this name is used as string in import table.
4292 Note: The @code{IMPORTS} has to be the last command in .def file, as keywords
4293 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4294 If you want to use LIBRARY as name then you need to quote it.
4295
4296 @item @code{DESCRIPTION} @var{string}
4297 Puts @var{string} into the output @file{.exp} file in the
4298 @code{.rdata} section.
4299
4300 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4301 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4302 Generates @code{--stack} or @code{--heap}
4303 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
4304 section. The linker will see this and act upon it.
4305
4306 @item @code{CODE} @var{attr} @code{+}
4307 @item @code{DATA} @var{attr} @code{+}
4308 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
4309 Generates @code{--attr} @var{section-name} @var{attr} in the output
4310 @code{.drectve} section, where @var{attr} is one of @code{READ},
4311 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
4312 this and act upon it.
4313
4314 @end table
4315
4316 @ignore
4317 @c man begin SEEALSO dlltool
4318 The Info pages for @file{binutils}.
4319 @c man end
4320 @end ignore
4321
4322 @node readelf
4323 @chapter readelf
4324
4325 @cindex ELF file information
4326 @kindex readelf
4327
4328 @c man title readelf Displays information about ELF files.
4329
4330 @smallexample
4331 @c man begin SYNOPSIS readelf
4332 readelf [@option{-a}|@option{--all}]
4333 [@option{-h}|@option{--file-header}]
4334 [@option{-l}|@option{--program-headers}|@option{--segments}]
4335 [@option{-S}|@option{--section-headers}|@option{--sections}]
4336 [@option{-g}|@option{--section-groups}]
4337 [@option{-t}|@option{--section-details}]
4338 [@option{-e}|@option{--headers}]
4339 [@option{-s}|@option{--syms}|@option{--symbols}]
4340 [@option{--dyn-syms}]
4341 [@option{-n}|@option{--notes}]
4342 [@option{-r}|@option{--relocs}]
4343 [@option{-u}|@option{--unwind}]
4344 [@option{-d}|@option{--dynamic}]
4345 [@option{-V}|@option{--version-info}]
4346 [@option{-A}|@option{--arch-specific}]
4347 [@option{-D}|@option{--use-dynamic}]
4348 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
4349 [@option{-p} <number or name>|@option{--string-dump=}<number or name>]
4350 [@option{-R} <number or name>|@option{--relocated-dump=}<number or name>]
4351 [@option{-z}|@option{--decompress}]
4352 [@option{-c}|@option{--archive-index}]
4353 [@option{-w[lLiaprmfFsoRt]}|
4354 @option{--debug-dump}[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index]]
4355 [@option{--dwarf-depth=@var{n}}]
4356 [@option{--dwarf-start=@var{n}}]
4357 [@option{-I}|@option{--histogram}]
4358 [@option{-v}|@option{--version}]
4359 [@option{-W}|@option{--wide}]
4360 [@option{-H}|@option{--help}]
4361 @var{elffile}@dots{}
4362 @c man end
4363 @end smallexample
4364
4365 @c man begin DESCRIPTION readelf
4366
4367 @command{readelf} displays information about one or more ELF format object
4368 files. The options control what particular information to display.
4369
4370 @var{elffile}@dots{} are the object files to be examined. 32-bit and
4371 64-bit ELF files are supported, as are archives containing ELF files.
4372
4373 This program performs a similar function to @command{objdump} but it
4374 goes into more detail and it exists independently of the @sc{bfd}
4375 library, so if there is a bug in @sc{bfd} then readelf will not be
4376 affected.
4377
4378 @c man end
4379
4380 @c man begin OPTIONS readelf
4381
4382 The long and short forms of options, shown here as alternatives, are
4383 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
4384 given.
4385
4386 @table @env
4387 @item -a
4388 @itemx --all
4389 Equivalent to specifying @option{--file-header},
4390 @option{--program-headers}, @option{--sections}, @option{--symbols},
4391 @option{--relocs}, @option{--dynamic}, @option{--notes} and
4392 @option{--version-info}.
4393
4394 @item -h
4395 @itemx --file-header
4396 @cindex ELF file header information
4397 Displays the information contained in the ELF header at the start of the
4398 file.
4399
4400 @item -l
4401 @itemx --program-headers
4402 @itemx --segments
4403 @cindex ELF program header information
4404 @cindex ELF segment information
4405 Displays the information contained in the file's segment headers, if it
4406 has any.
4407
4408 @item -S
4409 @itemx --sections
4410 @itemx --section-headers
4411 @cindex ELF section information
4412 Displays the information contained in the file's section headers, if it
4413 has any.
4414
4415 @item -g
4416 @itemx --section-groups
4417 @cindex ELF section group information
4418 Displays the information contained in the file's section groups, if it
4419 has any.
4420
4421 @item -t
4422 @itemx --section-details
4423 @cindex ELF section information
4424 Displays the detailed section information. Implies @option{-S}.
4425
4426 @item -s
4427 @itemx --symbols
4428 @itemx --syms
4429 @cindex ELF symbol table information
4430 Displays the entries in symbol table section of the file, if it has one.
4431
4432 @item --dyn-syms
4433 @cindex ELF dynamic symbol table information
4434 Displays the entries in dynamic symbol table section of the file, if it
4435 has one.
4436
4437 @item -e
4438 @itemx --headers
4439 Display all the headers in the file. Equivalent to @option{-h -l -S}.
4440
4441 @item -n
4442 @itemx --notes
4443 @cindex ELF notes
4444 Displays the contents of the NOTE segments and/or sections, if any.
4445
4446 @item -r
4447 @itemx --relocs
4448 @cindex ELF reloc information
4449 Displays the contents of the file's relocation section, if it has one.
4450
4451 @item -u
4452 @itemx --unwind
4453 @cindex unwind information
4454 Displays the contents of the file's unwind section, if it has one. Only
4455 the unwind sections for IA64 ELF files, as well as ARM unwind tables
4456 (@code{.ARM.exidx} / @code{.ARM.extab}) are currently supported.
4457
4458 @item -d
4459 @itemx --dynamic
4460 @cindex ELF dynamic section information
4461 Displays the contents of the file's dynamic section, if it has one.
4462
4463 @item -V
4464 @itemx --version-info
4465 @cindex ELF version sections information
4466 Displays the contents of the version sections in the file, it they
4467 exist.
4468
4469 @item -A
4470 @itemx --arch-specific
4471 Displays architecture-specific information in the file, if there
4472 is any.
4473
4474 @item -D
4475 @itemx --use-dynamic
4476 When displaying symbols, this option makes @command{readelf} use the
4477 symbol hash tables in the file's dynamic section, rather than the
4478 symbol table sections.
4479
4480 @item -x <number or name>
4481 @itemx --hex-dump=<number or name>
4482 Displays the contents of the indicated section as a hexadecimal bytes.
4483 A number identifies a particular section by index in the section table;
4484 any other string identifies all sections with that name in the object file.
4485
4486 @item -R <number or name>
4487 @itemx --relocated-dump=<number or name>
4488 Displays the contents of the indicated section as a hexadecimal
4489 bytes. A number identifies a particular section by index in the
4490 section table; any other string identifies all sections with that name
4491 in the object file. The contents of the section will be relocated
4492 before they are displayed.
4493
4494 @item -p <number or name>
4495 @itemx --string-dump=<number or name>
4496 Displays the contents of the indicated section as printable strings.
4497 A number identifies a particular section by index in the section table;
4498 any other string identifies all sections with that name in the object file.
4499
4500 @item -z
4501 @itemx --decompress
4502 Requests that the section(s) being dumped by @option{x}, @option{R} or
4503 @option{p} options are decompressed before being displayed. If the
4504 section(s) are not compressed then they are displayed as is.
4505
4506 @item -c
4507 @itemx --archive-index
4508 @cindex Archive file symbol index information
4509 Displays the file symbol index information contained in the header part
4510 of binary archives. Performs the same function as the @option{t}
4511 command to @command{ar}, but without using the BFD library. @xref{ar}.
4512
4513 @item -w[lLiaprmfFsoRt]
4514 @itemx --debug-dump[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index]
4515 Displays the contents of the debug sections in the file, if any are
4516 present. If one of the optional letters or words follows the switch
4517 then only data found in those specific sections will be dumped.
4518
4519 Note that there is no single letter option to display the content of
4520 trace sections or .gdb_index.
4521
4522 Note: the @option{=decodedline} option will display the interpreted
4523 contents of a .debug_line section whereas the @option{=rawline} option
4524 dumps the contents in a raw format.
4525
4526 Note: the @option{=frames-interp} option will display the interpreted
4527 contents of a .debug_frame section whereas the @option{=frames} option
4528 dumps the contents in a raw format.
4529
4530 Note: the output from the @option{=info} option can also be affected
4531 by the options @option{--dwarf-depth} and @option{--dwarf-start}.
4532
4533 @item --dwarf-depth=@var{n}
4534 Limit the dump of the @code{.debug_info} section to @var{n} children.
4535 This is only useful with @option{--debug-dump=info}. The default is
4536 to print all DIEs; the special value 0 for @var{n} will also have this
4537 effect.
4538
4539 With a non-zero value for @var{n}, DIEs at or deeper than @var{n}
4540 levels will not be printed. The range for @var{n} is zero-based.
4541
4542 @item --dwarf-start=@var{n}
4543 Print only DIEs beginning with the DIE numbered @var{n}. This is only
4544 useful with @option{--debug-dump=info}.
4545
4546 If specified, this option will suppress printing of any header
4547 information and all DIEs before the DIE numbered @var{n}. Only
4548 siblings and children of the specified DIE will be printed.
4549
4550 This can be used in conjunction with @option{--dwarf-depth}.
4551
4552 @item -I
4553 @itemx --histogram
4554 Display a histogram of bucket list lengths when displaying the contents
4555 of the symbol tables.
4556
4557 @item -v
4558 @itemx --version
4559 Display the version number of readelf.
4560
4561 @item -W
4562 @itemx --wide
4563 Don't break output lines to fit into 80 columns. By default
4564 @command{readelf} breaks section header and segment listing lines for
4565 64-bit ELF files, so that they fit into 80 columns. This option causes
4566 @command{readelf} to print each section header resp. each segment one a
4567 single line, which is far more readable on terminals wider than 80 columns.
4568
4569 @item -H
4570 @itemx --help
4571 Display the command line options understood by @command{readelf}.
4572
4573 @end table
4574
4575 @c man end
4576
4577 @ignore
4578 @c man begin SEEALSO readelf
4579 objdump(1), and the Info entries for @file{binutils}.
4580 @c man end
4581 @end ignore
4582
4583 @node elfedit
4584 @chapter elfedit
4585
4586 @cindex Update ELF header
4587 @kindex elfedit
4588
4589 @c man title elfedit Update the ELF header of ELF files.
4590
4591 @smallexample
4592 @c man begin SYNOPSIS elfedit
4593 elfedit [@option{--input-mach=}@var{machine}]
4594 [@option{--input-type=}@var{type}]
4595 [@option{--input-osabi=}@var{osabi}]
4596 @option{--output-mach=}@var{machine}
4597 @option{--output-type=}@var{type}
4598 @option{--output-osabi=}@var{osabi}
4599 [@option{-v}|@option{--version}]
4600 [@option{-h}|@option{--help}]
4601 @var{elffile}@dots{}
4602 @c man end
4603 @end smallexample
4604
4605 @c man begin DESCRIPTION elfedit
4606
4607 @command{elfedit} updates the ELF header of ELF files which have
4608 the matching ELF machine and file types. The options control how and
4609 which fields in the ELF header should be updated.
4610
4611 @var{elffile}@dots{} are the ELF files to be updated. 32-bit and
4612 64-bit ELF files are supported, as are archives containing ELF files.
4613 @c man end
4614
4615 @c man begin OPTIONS elfedit
4616
4617 The long and short forms of options, shown here as alternatives, are
4618 equivalent. At least one of the @option{--output-mach},
4619 @option{--output-type} and @option{--output-osabi} options must be given.
4620
4621 @table @env
4622
4623 @item --input-mach=@var{machine}
4624 Set the matching input ELF machine type to @var{machine}. If
4625 @option{--input-mach} isn't specified, it will match any ELF
4626 machine types.
4627
4628 The supported ELF machine types are, @var{i386}, @var{IAMCU}, @var{L1OM},
4629 @var{K1OM} and @var{x86-64}.
4630
4631 @item --output-mach=@var{machine}
4632 Change the ELF machine type in the ELF header to @var{machine}. The
4633 supported ELF machine types are the same as @option{--input-mach}.
4634
4635 @item --input-type=@var{type}
4636 Set the matching input ELF file type to @var{type}. If
4637 @option{--input-type} isn't specified, it will match any ELF file types.
4638
4639 The supported ELF file types are, @var{rel}, @var{exec} and @var{dyn}.
4640
4641 @item --output-type=@var{type}
4642 Change the ELF file type in the ELF header to @var{type}. The
4643 supported ELF types are the same as @option{--input-type}.
4644
4645 @item --input-osabi=@var{osabi}
4646 Set the matching input ELF file OSABI to @var{osabi}. If
4647 @option{--input-osabi} isn't specified, it will match any ELF OSABIs.
4648
4649 The supported ELF OSABIs are, @var{none}, @var{HPUX}, @var{NetBSD},
4650 @var{GNU}, @var{Linux} (alias for @var{GNU}),
4651 @var{Solaris}, @var{AIX}, @var{Irix},
4652 @var{FreeBSD}, @var{TRU64}, @var{Modesto}, @var{OpenBSD}, @var{OpenVMS},
4653 @var{NSK}, @var{AROS} and @var{FenixOS}.
4654
4655 @item --output-osabi=@var{osabi}
4656 Change the ELF OSABI in the ELF header to @var{osabi}. The
4657 supported ELF OSABI are the same as @option{--input-osabi}.
4658
4659 @item -v
4660 @itemx --version
4661 Display the version number of @command{elfedit}.
4662
4663 @item -h
4664 @itemx --help
4665 Display the command line options understood by @command{elfedit}.
4666
4667 @end table
4668
4669 @c man end
4670
4671 @ignore
4672 @c man begin SEEALSO elfedit
4673 readelf(1), and the Info entries for @file{binutils}.
4674 @c man end
4675 @end ignore
4676
4677 @node Common Options
4678 @chapter Common Options
4679
4680 The following command-line options are supported by all of the
4681 programs described in this manual.
4682
4683 @c man begin OPTIONS
4684 @table @env
4685 @include at-file.texi
4686 @c man end
4687
4688 @item --help
4689 Display the command-line options supported by the program.
4690
4691 @item --version
4692 Display the version number of the program.
4693
4694 @c man begin OPTIONS
4695 @end table
4696 @c man end
4697
4698 @node Selecting the Target System
4699 @chapter Selecting the Target System
4700
4701 You can specify two aspects of the target system to the @sc{gnu}
4702 binary file utilities, each in several ways:
4703
4704 @itemize @bullet
4705 @item
4706 the target
4707
4708 @item
4709 the architecture
4710 @end itemize
4711
4712 In the following summaries, the lists of ways to specify values are in
4713 order of decreasing precedence. The ways listed first override those
4714 listed later.
4715
4716 The commands to list valid values only list the values for which the
4717 programs you are running were configured. If they were configured with
4718 @option{--enable-targets=all}, the commands list most of the available
4719 values, but a few are left out; not all targets can be configured in at
4720 once because some of them can only be configured @dfn{native} (on hosts
4721 with the same type as the target system).
4722
4723 @menu
4724 * Target Selection::
4725 * Architecture Selection::
4726 @end menu
4727
4728 @node Target Selection
4729 @section Target Selection
4730
4731 A @dfn{target} is an object file format. A given target may be
4732 supported for multiple architectures (@pxref{Architecture Selection}).
4733 A target selection may also have variations for different operating
4734 systems or architectures.
4735
4736 The command to list valid target values is @samp{objdump -i}
4737 (the first column of output contains the relevant information).
4738
4739 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
4740 @samp{a.out-sunos-big}.
4741
4742 You can also specify a target using a configuration triplet. This is
4743 the same sort of name that is passed to @file{configure} to specify a
4744 target. When you use a configuration triplet as an argument, it must be
4745 fully canonicalized. You can see the canonical version of a triplet by
4746 running the shell script @file{config.sub} which is included with the
4747 sources.
4748
4749 Some sample configuration triplets are: @samp{m68k-hp-bsd},
4750 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
4751
4752 @subheading @command{objdump} Target
4753
4754 Ways to specify:
4755
4756 @enumerate
4757 @item
4758 command line option: @option{-b} or @option{--target}
4759
4760 @item
4761 environment variable @code{GNUTARGET}
4762
4763 @item
4764 deduced from the input file
4765 @end enumerate
4766
4767 @subheading @command{objcopy} and @command{strip} Input Target
4768
4769 Ways to specify:
4770
4771 @enumerate
4772 @item
4773 command line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
4774
4775 @item
4776 environment variable @code{GNUTARGET}
4777
4778 @item
4779 deduced from the input file
4780 @end enumerate
4781
4782 @subheading @command{objcopy} and @command{strip} Output Target
4783
4784 Ways to specify:
4785
4786 @enumerate
4787 @item
4788 command line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
4789
4790 @item
4791 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
4792
4793 @item
4794 environment variable @code{GNUTARGET}
4795
4796 @item
4797 deduced from the input file
4798 @end enumerate
4799
4800 @subheading @command{nm}, @command{size}, and @command{strings} Target
4801
4802 Ways to specify:
4803
4804 @enumerate
4805 @item
4806 command line option: @option{--target}
4807
4808 @item
4809 environment variable @code{GNUTARGET}
4810
4811 @item
4812 deduced from the input file
4813 @end enumerate
4814
4815 @node Architecture Selection
4816 @section Architecture Selection
4817
4818 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
4819 to run. Its name may contain a colon, separating the name of the
4820 processor family from the name of the particular @sc{cpu}.
4821
4822 The command to list valid architecture values is @samp{objdump -i} (the
4823 second column contains the relevant information).
4824
4825 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
4826
4827 @subheading @command{objdump} Architecture
4828
4829 Ways to specify:
4830
4831 @enumerate
4832 @item
4833 command line option: @option{-m} or @option{--architecture}
4834
4835 @item
4836 deduced from the input file
4837 @end enumerate
4838
4839 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
4840
4841 Ways to specify:
4842
4843 @enumerate
4844 @item
4845 deduced from the input file
4846 @end enumerate
4847
4848 @node Reporting Bugs
4849 @chapter Reporting Bugs
4850 @cindex bugs
4851 @cindex reporting bugs
4852
4853 Your bug reports play an essential role in making the binary utilities
4854 reliable.
4855
4856 Reporting a bug may help you by bringing a solution to your problem, or
4857 it may not. But in any case the principal function of a bug report is
4858 to help the entire community by making the next version of the binary
4859 utilities work better. Bug reports are your contribution to their
4860 maintenance.
4861
4862 In order for a bug report to serve its purpose, you must include the
4863 information that enables us to fix the bug.
4864
4865 @menu
4866 * Bug Criteria:: Have you found a bug?
4867 * Bug Reporting:: How to report bugs
4868 @end menu
4869
4870 @node Bug Criteria
4871 @section Have You Found a Bug?
4872 @cindex bug criteria
4873
4874 If you are not sure whether you have found a bug, here are some guidelines:
4875
4876 @itemize @bullet
4877 @cindex fatal signal
4878 @cindex crash
4879 @item
4880 If a binary utility gets a fatal signal, for any input whatever, that is
4881 a bug. Reliable utilities never crash.
4882
4883 @cindex error on valid input
4884 @item
4885 If a binary utility produces an error message for valid input, that is a
4886 bug.
4887
4888 @item
4889 If you are an experienced user of binary utilities, your suggestions for
4890 improvement are welcome in any case.
4891 @end itemize
4892
4893 @node Bug Reporting
4894 @section How to Report Bugs
4895 @cindex bug reports
4896 @cindex bugs, reporting
4897
4898 A number of companies and individuals offer support for @sc{gnu}
4899 products. If you obtained the binary utilities from a support
4900 organization, we recommend you contact that organization first.
4901
4902 You can find contact information for many support companies and
4903 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
4904 distribution.
4905
4906 @ifset BUGURL
4907 In any event, we also recommend that you send bug reports for the binary
4908 utilities to @value{BUGURL}.
4909 @end ifset
4910
4911 The fundamental principle of reporting bugs usefully is this:
4912 @strong{report all the facts}. If you are not sure whether to state a
4913 fact or leave it out, state it!
4914
4915 Often people omit facts because they think they know what causes the
4916 problem and assume that some details do not matter. Thus, you might
4917 assume that the name of a file you use in an example does not matter.
4918 Well, probably it does not, but one cannot be sure. Perhaps the bug is
4919 a stray memory reference which happens to fetch from the location where
4920 that pathname is stored in memory; perhaps, if the pathname were
4921 different, the contents of that location would fool the utility into
4922 doing the right thing despite the bug. Play it safe and give a
4923 specific, complete example. That is the easiest thing for you to do,
4924 and the most helpful.
4925
4926 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
4927 it is new to us. Therefore, always write your bug reports on the assumption
4928 that the bug has not been reported previously.
4929
4930 Sometimes people give a few sketchy facts and ask, ``Does this ring a
4931 bell?'' This cannot help us fix a bug, so it is basically useless. We
4932 respond by asking for enough details to enable us to investigate.
4933 You might as well expedite matters by sending them to begin with.
4934
4935 To enable us to fix the bug, you should include all these things:
4936
4937 @itemize @bullet
4938 @item
4939 The version of the utility. Each utility announces it if you start it
4940 with the @option{--version} argument.
4941
4942 Without this, we will not know whether there is any point in looking for
4943 the bug in the current version of the binary utilities.
4944
4945 @item
4946 Any patches you may have applied to the source, including any patches
4947 made to the @code{BFD} library.
4948
4949 @item
4950 The type of machine you are using, and the operating system name and
4951 version number.
4952
4953 @item
4954 What compiler (and its version) was used to compile the utilities---e.g.
4955 ``@code{gcc-2.7}''.
4956
4957 @item
4958 The command arguments you gave the utility to observe the bug. To
4959 guarantee you will not omit something important, list them all. A copy
4960 of the Makefile (or the output from make) is sufficient.
4961
4962 If we were to try to guess the arguments, we would probably guess wrong
4963 and then we might not encounter the bug.
4964
4965 @item
4966 A complete input file, or set of input files, that will reproduce the
4967 bug. If the utility is reading an object file or files, then it is
4968 generally most helpful to send the actual object files.
4969
4970 If the source files were produced exclusively using @sc{gnu} programs
4971 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
4972 may be OK to send the source files rather than the object files. In
4973 this case, be sure to say exactly what version of @command{gcc}, or
4974 whatever, was used to produce the object files. Also say how
4975 @command{gcc}, or whatever, was configured.
4976
4977 @item
4978 A description of what behavior you observe that you believe is
4979 incorrect. For example, ``It gets a fatal signal.''
4980
4981 Of course, if the bug is that the utility gets a fatal signal, then we
4982 will certainly notice it. But if the bug is incorrect output, we might
4983 not notice unless it is glaringly wrong. You might as well not give us
4984 a chance to make a mistake.
4985
4986 Even if the problem you experience is a fatal signal, you should still
4987 say so explicitly. Suppose something strange is going on, such as your
4988 copy of the utility is out of sync, or you have encountered a bug in
4989 the C library on your system. (This has happened!) Your copy might
4990 crash and ours would not. If you told us to expect a crash, then when
4991 ours fails to crash, we would know that the bug was not happening for
4992 us. If you had not told us to expect a crash, then we would not be able
4993 to draw any conclusion from our observations.
4994
4995 @item
4996 If you wish to suggest changes to the source, send us context diffs, as
4997 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
4998 option. Always send diffs from the old file to the new file. If you
4999 wish to discuss something in the @command{ld} source, refer to it by
5000 context, not by line number.
5001
5002 The line numbers in our development sources will not match those in your
5003 sources. Your line numbers would convey no useful information to us.
5004 @end itemize
5005
5006 Here are some things that are not necessary:
5007
5008 @itemize @bullet
5009 @item
5010 A description of the envelope of the bug.
5011
5012 Often people who encounter a bug spend a lot of time investigating
5013 which changes to the input file will make the bug go away and which
5014 changes will not affect it.
5015
5016 This is often time consuming and not very useful, because the way we
5017 will find the bug is by running a single example under the debugger
5018 with breakpoints, not by pure deduction from a series of examples.
5019 We recommend that you save your time for something else.
5020
5021 Of course, if you can find a simpler example to report @emph{instead}
5022 of the original one, that is a convenience for us. Errors in the
5023 output will be easier to spot, running under the debugger will take
5024 less time, and so on.
5025
5026 However, simplification is not vital; if you do not want to do this,
5027 report the bug anyway and send us the entire test case you used.
5028
5029 @item
5030 A patch for the bug.
5031
5032 A patch for the bug does help us if it is a good one. But do not omit
5033 the necessary information, such as the test case, on the assumption that
5034 a patch is all we need. We might see problems with your patch and decide
5035 to fix the problem another way, or we might not understand it at all.
5036
5037 Sometimes with programs as complicated as the binary utilities it is
5038 very hard to construct an example that will make the program follow a
5039 certain path through the code. If you do not send us the example, we
5040 will not be able to construct one, so we will not be able to verify that
5041 the bug is fixed.
5042
5043 And if we cannot understand what bug you are trying to fix, or why your
5044 patch should be an improvement, we will not install it. A test case will
5045 help us to understand.
5046
5047 @item
5048 A guess about what the bug is or what it depends on.
5049
5050 Such guesses are usually wrong. Even we cannot guess right about such
5051 things without first using the debugger to find the facts.
5052 @end itemize
5053
5054 @node GNU Free Documentation License
5055 @appendix GNU Free Documentation License
5056
5057 @include fdl.texi
5058
5059 @node Binutils Index
5060 @unnumbered Binutils Index
5061
5062 @printindex cp
5063
5064 @bye