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1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @include config.texi
4
5 @ifinfo
6 @format
7 START-INFO-DIR-ENTRY
8 * Binutils: (binutils). The GNU binary utilities "ar", "objcopy",
9 "objdump", "nm", "nlmconv", "size",
10 "strings", "strip", and "ranlib".
11 END-INFO-DIR-ENTRY
12 @end format
13 @end ifinfo
14
15 @ifinfo
16 Copyright @copyright{} 1991, 92, 93, 94, 95, 1996 Free Software Foundation, Inc.
17
18 Permission is granted to make and distribute verbatim copies of
19 this manual provided the copyright notice and this permission notice
20 are preserved on all copies.
21
22 @ignore
23 Permission is granted to process this file through TeX and print the
24 results, provided the printed document carries a copying permission
25 notice identical to this one except for the removal of this paragraph
26 (this paragraph not being relevant to the printed manual).
27
28 @end ignore
29
30 Permission is granted to copy and distribute modified versions of this
31 manual under the conditions for verbatim copying, provided also that
32 the entire resulting derived work is distributed under the terms of a
33 permission notice identical to this one.
34
35 Permission is granted to copy and distribute translations of this manual
36 into another language, under the above conditions for modified versions.
37 @end ifinfo
38
39 @synindex ky cp
40 @c
41 @c This file documents the GNU binary utilities "ar", "ld", "objcopy",
42 @c "objdump", "nm", "size", "strings", "strip", and "ranlib".
43 @c
44 @c Copyright (C) 1991, 92, 93, 94, 95, 1996 Free Software Foundation, Inc.
45 @c
46 @c This text may be freely distributed under the terms of the GNU
47 @c General Public License.
48 @c
49
50 @setchapternewpage odd
51 @settitle @sc{gnu} Binary Utilities
52 @titlepage
53 @finalout
54 @title The @sc{gnu} Binary Utilities
55 @subtitle Version @value{VERSION}
56 @sp 1
57 @subtitle May 1993
58 @author Roland H. Pesch
59 @author Jeffrey M. Osier
60 @author Cygnus Support
61 @page
62
63 @tex
64 {\parskip=0pt \hfill Cygnus Support\par \hfill
65 \TeX{}info \texinfoversion\par }
66 @end tex
67
68 @vskip 0pt plus 1filll
69 Copyright @copyright{} 1991, 92, 93, 94, 95, 1996 Free Software Foundation, Inc.
70
71 Permission is granted to make and distribute verbatim copies of
72 this manual provided the copyright notice and this permission notice
73 are preserved on all copies.
74
75 Permission is granted to copy and distribute modified versions of this
76 manual under the conditions for verbatim copying, provided also that
77 the entire resulting derived work is distributed under the terms of a
78 permission notice identical to this one.
79
80 Permission is granted to copy and distribute translations of this manual
81 into another language, under the above conditions for modified versions.
82 @end titlepage
83
84 @node Top
85 @top Introduction
86
87 @cindex version
88 This brief manual contains preliminary documentation for the @sc{gnu} binary
89 utilities (collectively version @value{VERSION}):
90
91 @iftex
92 @table @code
93 @item ar
94 Create, modify, and extract from archives
95
96 @item nm
97 List symbols from object files
98
99 @item objcopy
100 Copy and translate object files
101
102 @item objdump
103 Display information from object files
104
105 @item ranlib
106 Generate index to archive contents
107
108 @item size
109 List file section sizes and total size
110
111 @item strings
112 List printable strings from files
113
114 @item strip
115 Discard symbols
116
117 @item c++filt
118 Demangle encoded C++ symbols
119
120 @item nlmconv
121 Convert object code into a Netware Loadable Module
122 @end table
123 @end iftex
124
125 @menu
126 * ar:: Create, modify, and extract from archives
127 * nm:: List symbols from object files
128 * objcopy:: Copy and translate object files
129 * objdump:: Display information from object files
130 * ranlib:: Generate index to archive contents
131 * size:: List section sizes and total size
132 * strings:: List printable strings from files
133 * strip:: Discard symbols
134 * c++filt:: Filter to demangle encoded C++ symbols
135 * nlmconv:: Converts object code into an NLM
136 * Selecting The Target System:: How these utilities determine the target.
137 * Index::
138 @end menu
139
140 @node ar
141 @chapter ar
142
143 @kindex ar
144 @cindex archives
145 @cindex collections of files
146 @smallexample
147 ar [-]@var{p}[@var{mod} [@var{relpos}]] @var{archive} [@var{member}@dots{}]
148 ar -M [ <mri-script ]
149 @end smallexample
150
151 The @sc{gnu} @code{ar} program creates, modifies, and extracts from
152 archives. An @dfn{archive} is a single file holding a collection of
153 other files in a structure that makes it possible to retrieve
154 the original individual files (called @dfn{members} of the archive).
155
156 The original files' contents, mode (permissions), timestamp, owner, and
157 group are preserved in the archive, and can be restored on
158 extraction.
159
160 @cindex name length
161 @sc{gnu} @code{ar} can maintain archives whose members have names of any
162 length; however, depending on how @code{ar} is configured on your
163 system, a limit on member-name length may be imposed for compatibility
164 with archive formats maintained with other tools. If it exists, the
165 limit is often 15 characters (typical of formats related to a.out) or 16
166 characters (typical of formats related to coff).
167
168 @cindex libraries
169 @code{ar} is considered a binary utility because archives of this sort
170 are most often used as @dfn{libraries} holding commonly needed
171 subroutines.
172
173 @cindex symbol index
174 @code{ar} creates an index to the symbols defined in relocatable
175 object modules in the archive when you specify the modifier @samp{s}.
176 Once created, this index is updated in the archive whenever @code{ar}
177 makes a change to its contents (save for the @samp{q} update operation).
178 An archive with such an index speeds up linking to the library, and
179 allows routines in the library to call each other without regard to
180 their placement in the archive.
181
182 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
183 table. If an archive lacks the table, another form of @code{ar} called
184 @code{ranlib} can be used to add just the table.
185
186 @cindex compatibility, @code{ar}
187 @cindex @code{ar} compatibility
188 @sc{gnu} @code{ar} is designed to be compatible with two different
189 facilities. You can control its activity using command-line options,
190 like the different varieties of @code{ar} on Unix systems; or, if you
191 specify the single command-line option @samp{-M}, you can control it
192 with a script supplied via standard input, like the MRI ``librarian''
193 program.
194
195 @menu
196 * ar cmdline:: Controlling @code{ar} on the command line
197 * ar scripts:: Controlling @code{ar} with a script
198 @end menu
199
200 @page
201 @node ar cmdline
202 @section Controlling @code{ar} on the command line
203
204 @smallexample
205 ar [-]@var{p}[@var{mod} [@var{relpos}]] @var{archive} [@var{member}@dots{}]
206 @end smallexample
207
208 @cindex Unix compatibility, @code{ar}
209 When you use @code{ar} in the Unix style, @code{ar} insists on at least two
210 arguments to execute: one keyletter specifying the @emph{operation}
211 (optionally accompanied by other keyletters specifying
212 @emph{modifiers}), and the archive name to act on.
213
214 Most operations can also accept further @var{member} arguments,
215 specifying particular files to operate on.
216
217 @sc{gnu} @code{ar} allows you to mix the operation code @var{p} and modifier
218 flags @var{mod} in any order, within the first command-line argument.
219
220 If you wish, you may begin the first command-line argument with a
221 dash.
222
223 @cindex operations on archive
224 The @var{p} keyletter specifies what operation to execute; it may be
225 any of the following, but you must specify only one of them:
226
227 @table @code
228 @item d
229 @cindex deleting from archive
230 @emph{Delete} modules from the archive. Specify the names of modules to
231 be deleted as @var{member}@dots{}; the archive is untouched if you
232 specify no files to delete.
233
234 If you specify the @samp{v} modifier, @code{ar} lists each module
235 as it is deleted.
236
237 @item m
238 @cindex moving in archive
239 Use this operation to @emph{move} members in an archive.
240
241 The ordering of members in an archive can make a difference in how
242 programs are linked using the library, if a symbol is defined in more
243 than one member.
244
245 If no modifiers are used with @code{m}, any members you name in the
246 @var{member} arguments are moved to the @emph{end} of the archive;
247 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
248 specified place instead.
249
250 @item p
251 @cindex printing from archive
252 @emph{Print} the specified members of the archive, to the standard
253 output file. If the @samp{v} modifier is specified, show the member
254 name before copying its contents to standard output.
255
256 If you specify no @var{member} arguments, all the files in the archive are
257 printed.
258
259 @item q
260 @cindex quick append to archive
261 @emph{Quick append}; add the files @var{member}@dots{} to the end of
262 @var{archive}, without checking for replacement.
263
264 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
265 operation; new members are always placed at the end of the archive.
266
267 The modifier @samp{v} makes @code{ar} list each file as it is appended.
268
269 Since the point of this operation is speed, the archive's symbol table
270 index is not updated, even if it already existed; you can use @samp{ar s} or
271 @code{ranlib} explicitly to update the symbol table index.
272
273 @item r
274 @cindex replacement in archive
275 Insert the files @var{member}@dots{} into @var{archive} (with
276 @emph{replacement}). This operation differs from @samp{q} in that any
277 previously existing members are deleted if their names match those being
278 added.
279
280 If one of the files named in @var{member}@dots{} does not exist, @code{ar}
281 displays an error message, and leaves undisturbed any existing members
282 of the archive matching that name.
283
284 By default, new members are added at the end of the file; but you may
285 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
286 placement relative to some existing member.
287
288 The modifier @samp{v} used with this operation elicits a line of
289 output for each file inserted, along with one of the letters @samp{a} or
290 @samp{r} to indicate whether the file was appended (no old member
291 deleted) or replaced.
292
293 @item t
294 @cindex contents of archive
295 Display a @emph{table} listing the contents of @var{archive}, or those
296 of the files listed in @var{member}@dots{} that are present in the
297 archive. Normally only the member name is shown; if you also want to
298 see the modes (permissions), timestamp, owner, group, and size, you can
299 request that by also specifying the @samp{v} modifier.
300
301 If you do not specify a @var{member}, all files in the archive
302 are listed.
303
304 @cindex repeated names in archive
305 @cindex name duplication in archive
306 If there is more than one file with the same name (say, @samp{fie}) in
307 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
308 first instance; to see them all, you must ask for a complete
309 listing---in our example, @samp{ar t b.a}.
310 @c WRS only; per Gumby, this is implementation-dependent, and in a more
311 @c recent case in fact works the other way.
312
313 @item x
314 @cindex extract from archive
315 @emph{Extract} members (named @var{member}) from the archive. You can
316 use the @samp{v} modifier with this operation, to request that
317 @code{ar} list each name as it extracts it.
318
319 If you do not specify a @var{member}, all files in the archive
320 are extracted.
321
322 @end table
323
324 A number of modifiers (@var{mod}) may immediately follow the @var{p}
325 keyletter, to specify variations on an operation's behavior:
326
327 @table @code
328 @item a
329 @cindex relative placement in archive
330 Add new files @emph{after} an existing member of the
331 archive. If you use the modifier @samp{a}, the name of an existing archive
332 member must be present as the @var{relpos} argument, before the
333 @var{archive} specification.
334
335 @item b
336 Add new files @emph{before} an existing member of the
337 archive. If you use the modifier @samp{b}, the name of an existing archive
338 member must be present as the @var{relpos} argument, before the
339 @var{archive} specification. (same as @samp{i}).
340
341 @item c
342 @cindex creating archives
343 @emph{Create} the archive. The specified @var{archive} is always
344 created if it did not exist, when you request an update. But a warning is
345 issued unless you specify in advance that you expect to create it, by
346 using this modifier.
347
348 @item f
349 Truncate names in the archive. @sc{gnu} @code{ar} will normally permit file
350 names of any length. This will cause it to create archives which are
351 not compatible with the native @code{ar} program on some systems. If
352 this is a concern, the @samp{f} modifier may be used to truncate file
353 names when putting them in the archive.
354
355 @item i
356 Insert new files @emph{before} an existing member of the
357 archive. If you use the modifier @samp{i}, the name of an existing archive
358 member must be present as the @var{relpos} argument, before the
359 @var{archive} specification. (same as @samp{b}).
360
361 @item l
362 This modifier is accepted but not used.
363 @c whaffor ar l modifier??? presumably compat; with
364 @c what???---doc@@cygnus.com, 25jan91
365
366 @item o
367 @cindex dates in archive
368 Preserve the @emph{original} dates of members when extracting them. If
369 you do not specify this modifier, files extracted from the archive
370 are stamped with the time of extraction.
371
372 @item s
373 @cindex writing archive index
374 Write an object-file index into the archive, or update an existing one,
375 even if no other change is made to the archive. You may use this modifier
376 flag either with any operation, or alone. Running @samp{ar s} on an
377 archive is equivalent to running @samp{ranlib} on it.
378
379 @item u
380 @cindex updating an archive
381 Normally, @samp{ar r}@dots{} inserts all files
382 listed into the archive. If you would like to insert @emph{only} those
383 of the files you list that are newer than existing members of the same
384 names, use this modifier. The @samp{u} modifier is allowed only for the
385 operation @samp{r} (replace). In particular, the combination @samp{qu} is
386 not allowed, since checking the timestamps would lose any speed
387 advantage from the operation @samp{q}.
388
389 @item v
390 This modifier requests the @emph{verbose} version of an operation. Many
391 operations display additional information, such as filenames processed,
392 when the modifier @samp{v} is appended.
393
394 @item V
395 This modifier shows the version number of @code{ar}.
396 @end table
397
398 @node ar scripts
399 @section Controlling @code{ar} with a script
400
401 @smallexample
402 ar -M [ <@var{script} ]
403 @end smallexample
404
405 @cindex MRI compatibility, @code{ar}
406 @cindex scripts, @code{ar}
407 If you use the single command-line option @samp{-M} with @code{ar}, you
408 can control its operation with a rudimentary command language. This
409 form of @code{ar} operates interactively if standard input is coming
410 directly from a terminal. During interactive use, @code{ar} prompts for
411 input (the prompt is @samp{AR >}), and continues executing even after
412 errors. If you redirect standard input to a script file, no prompts are
413 issued, and @code{ar} abandons execution (with a nonzero exit code)
414 on any error.
415
416 The @code{ar} command language is @emph{not} designed to be equivalent
417 to the command-line options; in fact, it provides somewhat less control
418 over archives. The only purpose of the command language is to ease the
419 transition to @sc{gnu} @code{ar} for developers who already have scripts
420 written for the MRI ``librarian'' program.
421
422 The syntax for the @code{ar} command language is straightforward:
423 @itemize @bullet
424 @item
425 commands are recognized in upper or lower case; for example, @code{LIST}
426 is the same as @code{list}. In the following descriptions, commands are
427 shown in upper case for clarity.
428
429 @item
430 a single command may appear on each line; it is the first word on the
431 line.
432
433 @item
434 empty lines are allowed, and have no effect.
435
436 @item
437 comments are allowed; text after either of the characters @samp{*}
438 or @samp{;} is ignored.
439
440 @item
441 Whenever you use a list of names as part of the argument to an @code{ar}
442 command, you can separate the individual names with either commas or
443 blanks. Commas are shown in the explanations below, for clarity.
444
445 @item
446 @samp{+} is used as a line continuation character; if @samp{+} appears
447 at the end of a line, the text on the following line is considered part
448 of the current command.
449 @end itemize
450
451 Here are the commands you can use in @code{ar} scripts, or when using
452 @code{ar} interactively. Three of them have special significance:
453
454 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
455 a temporary file required for most of the other commands.
456
457 @code{SAVE} commits the changes so far specified by the script. Prior
458 to @code{SAVE}, commands affect only the temporary copy of the current
459 archive.
460
461 @table @code
462 @item ADDLIB @var{archive}
463 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
464 Add all the contents of @var{archive} (or, if specified, each named
465 @var{module} from @var{archive}) to the current archive.
466
467 Requires prior use of @code{OPEN} or @code{CREATE}.
468
469 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
470 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
471 @c else like "ar q..."
472 Add each named @var{member} as a module in the current archive.
473
474 Requires prior use of @code{OPEN} or @code{CREATE}.
475
476 @item CLEAR
477 Discard the contents of the current archive, cancelling the effect of
478 any operations since the last @code{SAVE}. May be executed (with no
479 effect) even if no current archive is specified.
480
481 @item CREATE @var{archive}
482 Creates an archive, and makes it the current archive (required for many
483 other commands). The new archive is created with a temporary name; it
484 is not actually saved as @var{archive} until you use @code{SAVE}.
485 You can overwrite existing archives; similarly, the contents of any
486 existing file named @var{archive} will not be destroyed until @code{SAVE}.
487
488 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
489 Delete each listed @var{module} from the current archive; equivalent to
490 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
491
492 Requires prior use of @code{OPEN} or @code{CREATE}.
493
494 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
495 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
496 List each named @var{module} present in @var{archive}. The separate
497 command @code{VERBOSE} specifies the form of the output: when verbose
498 output is off, output is like that of @samp{ar -t @var{archive}
499 @var{module}@dots{}}. When verbose output is on, the listing is like
500 @samp{ar -tv @var{archive} @var{module}@dots{}}.
501
502 Output normally goes to the standard output stream; however, if you
503 specify @var{outputfile} as a final argument, @code{ar} directs the
504 output to that file.
505
506 @item END
507 Exit from @code{ar}, with a @code{0} exit code to indicate successful
508 completion. This command does not save the output file; if you have
509 changed the current archive since the last @code{SAVE} command, those
510 changes are lost.
511
512 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
513 Extract each named @var{module} from the current archive, writing them
514 into the current directory as separate files. Equivalent to @samp{ar -x
515 @var{archive} @var{module}@dots{}}.
516
517 Requires prior use of @code{OPEN} or @code{CREATE}.
518
519 @ignore
520 @c FIXME Tokens but no commands???
521 @item FULLDIR
522
523 @item HELP
524 @end ignore
525
526 @item LIST
527 Display full contents of the current archive, in ``verbose'' style
528 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
529 tv @var{archive}}). (This single command is a @sc{gnu} @code{ld}
530 enhancement, rather than present for MRI compatibility.)
531
532 Requires prior use of @code{OPEN} or @code{CREATE}.
533
534 @item OPEN @var{archive}
535 Opens an existing archive for use as the current archive (required for
536 many other commands). Any changes as the result of subsequent commands
537 will not actually affect @var{archive} until you next use @code{SAVE}.
538
539 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
540 In the current archive, replace each existing @var{module} (named in
541 the @code{REPLACE} arguments) from files in the current working directory.
542 To execute this command without errors, both the file, and the module in
543 the current archive, must exist.
544
545 Requires prior use of @code{OPEN} or @code{CREATE}.
546
547 @item VERBOSE
548 Toggle an internal flag governing the output from @code{DIRECTORY}.
549 When the flag is on, @code{DIRECTORY} output matches output from
550 @samp{ar -tv }@dots{}.
551
552 @item SAVE
553 Commit your changes to the current archive, and actually save it as a
554 file with the name specified in the last @code{CREATE} or @code{OPEN}
555 command.
556
557 Requires prior use of @code{OPEN} or @code{CREATE}.
558
559 @end table
560
561 @iftex
562 @node ld
563 @chapter ld
564 @cindex linker
565 @kindex ld
566 The @sc{gnu} linker @code{ld} is now described in a separate manual.
567 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
568 @end iftex
569
570 @node nm
571 @chapter nm
572 @cindex symbols
573 @kindex nm
574
575 @smallexample
576 nm [ -a | --debug-syms ] [ -g | --extern-only ]
577 [ -B ] [ -C | --demangle ] [ -D | --dynamic ]
578 [ -s | --print-armap ] [ -A | -o | --print-file-name ]
579 [ -n | -v | --numeric-sort ] [ -p | --no-sort ]
580 [ -r | --reverse-sort ] [ --size-sort ] [ -u | --undefined-only ]
581 [ -t @var{radix} | --radix=@var{radix} ] [ -P | --portability ]
582 [ --target=@var{bfdname} ] [ -f @var{format} | --format=@var{format} ]
583 [ --defined-only ]
584 [ --no-demangle ] [ -V | --version ] [ --help ] [ @var{objfile}@dots{} ]
585 @end smallexample
586
587 @sc{gnu} @code{nm} lists the symbols from object files @var{objfile}@dots{}.
588 If no object files are listed as arguments, @code{nm} assumes
589 @file{a.out}.
590
591 For each symbol, @code{nm} shows:
592
593 @itemize @bullet
594 @item
595 The symbol value, in the radix selected by options (see below), or
596 hexadecimal by default.
597
598 @item
599 The symbol type. At least the following types are used; others are, as
600 well, depending on the object file format. If lowercase, the symbol is
601 local; if uppercase, the symbol is global (external).
602
603 @c Some more detail on exactly what these symbol types are used for
604 @c would be nice.
605 @table @code
606 @item A
607 The symbol's value is absolute, and will not be changed by further
608 linking.
609
610 @item B
611 The symbol is in the uninitialized data section (known as BSS).
612
613 @item C
614 The symbol is common. Common symbols are uninitialized data. When
615 linking, multiple common symbols may appear with the same name. If the
616 symbol is defined anywhere, the common symbols are treated as undefined
617 references. For more details on common symbols, see the discussion of
618 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
619
620 @item D
621 The symbol is in the initialized data section.
622
623 @item G
624 The symbol is in an initialized data section for small objects. Some
625 object file formats permit more efficient access to small data objects,
626 such as a global int variable as opposed to a large global array.
627
628 @item I
629 The symbol is an indirect reference to another symbol. This is a GNU
630 extension to the a.out object file format which is rarely used.
631
632 @item N
633 The symbol is a debugging symbol.
634
635 @item R
636 The symbol is in a read only data section.
637
638 @item S
639 The symbol is in an uninitialized data section for small objects.
640
641 @item T
642 The symbol is in the text (code) section.
643
644 @item U
645 The symbol is undefined.
646
647 @item W
648 The symbol is weak. When a weak defined symbol is linked with a normal
649 defined symbol, the normal defined symbol is used with no error. When a
650 weak undefined symbol is linked and the symbol is not defined, the value
651 of the weak symbol becomes zero with no error.
652
653 @item -
654 The symbol is a stabs symbol in an a.out object file. In this case, the
655 next values printed are the stabs other field, the stabs desc field, and
656 the stab type. Stabs symbols are used to hold debugging information;
657 for more information, see @ref{Top,Stabs,Stabs Overview,stabs.info, The
658 ``stabs'' debug format}.
659
660 @item ?
661 The symbol type is unknown, or object file format specific.
662 @end table
663
664 @item
665 The symbol name.
666 @end itemize
667
668 The long and short forms of options, shown here as alternatives, are
669 equivalent.
670
671 @table @code
672 @item -A
673 @itemx -o
674 @itemx --print-file-name
675 @cindex input file name
676 @cindex file name
677 @cindex source file name
678 Precede each symbol by the name of the input file (or archive element)
679 in which it was found, rather than identifying the input file once only,
680 before all of its symbols.
681
682 @item -a
683 @itemx --debug-syms
684 @cindex debugging symbols
685 Display all symbols, even debugger-only symbols; normally these are not
686 listed.
687
688 @item -B
689 @cindex @code{nm} format
690 @cindex @code{nm} compatibility
691 The same as @samp{--format=bsd} (for compatibility with the MIPS @code{nm}).
692
693 @item -C
694 @itemx --demangle
695 @cindex demangling C++ symbols
696 Decode (@dfn{demangle}) low-level symbol names into user-level names.
697 Besides removing any initial underscore prepended by the system, this
698 makes C++ function names readable. @xref{c++filt}, for more information
699 on demangling.
700
701 @item --no-demangle
702 Do not demangle low-level symbol names. This is the default.
703
704 @item -D
705 @itemx --dynamic
706 @cindex dynamic symbols
707 Display the dynamic symbols rather than the normal symbols. This is
708 only meaningful for dynamic objects, such as certain types of shared
709 libraries.
710
711 @item -f @var{format}
712 @itemx --format=@var{format}
713 @cindex @code{nm} format
714 @cindex @code{nm} compatibility
715 Use the output format @var{format}, which can be @code{bsd},
716 @code{sysv}, or @code{posix}. The default is @code{bsd}.
717 Only the first character of @var{format} is significant; it can be
718 either upper or lower case.
719
720 @item -g
721 @itemx --extern-only
722 @cindex external symbols
723 Display only external symbols.
724
725 @item -n
726 @itemx -v
727 @itemx --numeric-sort
728 Sort symbols numerically by their addresses, rather than alphabetically
729 by their names.
730
731 @item -p
732 @itemx --no-sort
733 @cindex sorting symbols
734 Do not bother to sort the symbols in any order; print them in the order
735 encountered.
736
737 @item -P
738 @itemx --portability
739 Use the POSIX.2 standard output format instead of the default format.
740 Equivalent to @samp{-f posix}.
741
742 @item -s
743 @itemx --print-armap
744 @cindex symbol index, listing
745 When listing symbols from archive members, include the index: a mapping
746 (stored in the archive by @code{ar} or @code{ranlib}) of which modules
747 contain definitions for which names.
748
749 @item -r
750 @itemx --reverse-sort
751 Reverse the order of the sort (whether numeric or alphabetic); let the
752 last come first.
753
754 @item --size-sort
755 Sort symbols by size. The size is computed as the difference between
756 the value of the symbol and the value of the symbol with the next higher
757 value. The size of the symbol is printed, rather than the value.
758
759 @item -t @var{radix}
760 @itemx --radix=@var{radix}
761 Use @var{radix} as the radix for printing the symbol values. It must be
762 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
763
764 @item --target=@var{bfdname}
765 @cindex object code format
766 Specify an object code format other than your system's default format.
767 @xref{Target Selection}, for more information.
768
769 @item -u
770 @itemx --undefined-only
771 @cindex external symbols
772 @cindex undefined symbols
773 Display only undefined symbols (those external to each object file).
774
775 @item --defined-only
776 @cindex external symbols
777 @cindex undefined symbols
778 Display only defined symbols for each object file.
779
780 @item -V
781 @itemx --version
782 Show the version number of @code{nm} and exit.
783
784 @item --help
785 Show a summary of the options to @code{nm} and exit.
786 @end table
787
788 @node objcopy
789 @chapter objcopy
790
791 @smallexample
792 objcopy [ -F @var{bfdname} | --target=@var{bfdname} ]
793 [ -I @var{bfdname} | --input-target=@var{bfdname} ]
794 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
795 [ -S | --strip-all ] [ -g | --strip-debug ]
796 [ -K @var{symbolname} | --keep-symbol=@var{symbolname} ]
797 [ -N @var{symbolname} | --strip-symbol=@var{symbolname} ]
798 [ -x | --discard-all ] [ -X | --discard-locals ]
799 [ -b @var{byte} | --byte=@var{byte} ]
800 [ -i @var{interleave} | --interleave=@var{interleave} ]
801 [ -R @var{sectionname} | --remove-section=@var{sectionname} ]
802 [ --debugging ]
803 [ --gap-fill=@var{val} ] [ --pad-to=@var{address} ]
804 [ --set-start=@var{val} ] [ --adjust-start=@var{incr} ]
805 [ --adjust-vma=@var{incr} ]
806 [ --adjust-section-vma=@var{section}@{=,+,-@}@var{val} ]
807 [ --adjust-warnings ] [ --no-adjust-warnings ]
808 [ --set-section-flags=@var{section}=@var{flags} ]
809 [ --add-section=@var{sectionname}=@var{filename} ]
810 [ --remove-leading-char ]
811 [ -v | --verbose ] [ -V | --version ] [ --help ]
812 @var{infile} [@var{outfile}]
813 @end smallexample
814
815 The @sc{gnu} @code{objcopy} utility copies the contents of an object
816 file to another. @code{objcopy} uses the @sc{gnu} @sc{bfd} Library to
817 read and write the object files. It can write the destination object
818 file in a format different from that of the source object file. The
819 exact behavior of @code{objcopy} is controlled by command-line options.
820
821 @code{objcopy} creates temporary files to do its translations and
822 deletes them afterward. @code{objcopy} uses @sc{bfd} to do all its
823 translation work; it has access to all the formats described in @sc{bfd}
824 and thus is able to recognize most formats without being told
825 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
826
827 @code{objcopy} can be used to generate S-records by using an output
828 target of @samp{srec} (e.g., use @samp{-O srec}).
829
830 @code{objcopy} can be used to generate a raw binary file by using an
831 output target of @samp{binary} (e.g., use @samp{-O binary}). When
832 @code{objcopy} generates a raw binary file, it will essentially produce
833 a memory dump of the contents of the input object file. All symbols and
834 relocation information will be discarded. The memory dump will start at
835 the virtual address of the lowest section copied into the output file.
836
837 When generating an S-record or a raw binary file, it may be helpful to
838 use @samp{-S} to remove sections containing debugging information. In
839 some cases @samp{-R} will be useful to remove sections which contain
840 information which is not needed by the binary file.
841
842 @table @code
843 @item @var{infile}
844 @itemx @var{outfile}
845 The source and output files, respectively.
846 If you do not specify @var{outfile}, @code{objcopy} creates a
847 temporary file and destructively renames the result with
848 the name of @var{infile}.
849
850 @item -I @var{bfdname}
851 @itemx --input-target=@var{bfdname}
852 Consider the source file's object format to be @var{bfdname}, rather than
853 attempting to deduce it. @xref{Target Selection}, for more information.
854
855 @item -O @var{bfdname}
856 @itemx --output-target=@var{bfdname}
857 Write the output file using the object format @var{bfdname}.
858 @xref{Target Selection}, for more information.
859
860 @item -F @var{bfdname}
861 @itemx --target=@var{bfdname}
862 Use @var{bfdname} as the object format for both the input and the output
863 file; i.e., simply transfer data from source to destination with no
864 translation. @xref{Target Selection}, for more information.
865
866 @item -R @var{sectionname}
867 @itemx --remove-section=@var{sectionname}
868 Remove any section named @var{sectionname} from the output file. This
869 option may be given more than once. Note that using this option
870 inappropriately may make the output file unusable.
871
872 @item -S
873 @itemx --strip-all
874 Do not copy relocation and symbol information from the source file.
875
876 @item -g
877 @itemx --strip-debug
878 Do not copy debugging symbols from the source file.
879
880 @item --strip-unneeded
881 Strip all symbols that are not needed for relocation processing.
882
883 @item -K @var{symbolname}
884 @itemx --keep-symbol=@var{symbolname}
885 Copy only symbol @var{symbolname} from the source file. This option may
886 be given more than once.
887
888 @item -N @var{symbolname}
889 @itemx --strip-symbol=@var{symbolname}
890 Do not copy symbol @var{symbolname} from the source file. This option
891 may be given more than once, and may be combined with strip options
892 other than @code{-K}.
893
894 @item -x
895 @itemx --discard-all
896 Do not copy non-global symbols from the source file.
897 @c FIXME any reason to prefer "non-global" to "local" here?
898
899 @item -X
900 @itemx --discard-locals
901 Do not copy compiler-generated local symbols.
902 (These usually start with @samp{L} or @samp{.}.)
903
904 @item -b @var{byte}
905 @itemx --byte=@var{byte}
906 Keep only every @var{byte}th byte of the input file (header data is not
907 affected). @var{byte} can be in the range from 0 to @var{interleave}-1,
908 where @var{interleave} is given by the @samp{-i} or @samp{--interleave}
909 option, or the default of 4. This option is useful for creating files
910 to program @sc{rom}. It is typically used with an @code{srec} output
911 target.
912
913 @item -i @var{interleave}
914 @itemx --interleave=@var{interleave}
915 Only copy one out of every @var{interleave} bytes. Select which byte to
916 copy with the @var{-b} or @samp{--byte} option. The default is 4.
917 @code{objcopy} ignores this option if you do not specify either @samp{-b} or
918 @samp{--byte}.
919
920 @item --debugging
921 Convert debugging information, if possible. This is not the default
922 because only certain debugging formats are supported, and the
923 conversion process can be time consuming.
924
925 @item --gap-fill @var{val}
926 Fill gaps between sections with @var{val}. This is done by increasing
927 the size of the section with the lower address, and filling in the extra
928 space created with @var{val}.
929
930 @item --pad-to @var{address}
931 Pad the output file up to the virtual address @var{address}. This is
932 done by increasing the size of the last section. The extra space is
933 filled in with the value specified by @samp{--gap-fill} (default zero).
934
935 @item --set-start @var{val}
936 Set the address of the new file to @var{val}. Not all object file
937 formats support setting the start address.
938
939 @item --adjust-start @var{incr}
940 Adjust the start address by adding @var{incr}. Not all object file
941 formats support setting the start address.
942
943 @item --adjust-vma @var{incr}
944 Adjust the address of all sections, as well as the start address, by
945 adding @var{incr}. Some object file formats do not permit section
946 addresses to be changed arbitrarily. Note that this does not relocate
947 the sections; if the program expects sections to be loaded at a certain
948 address, and this option is used to change the sections such that they
949 are loaded at a different address, the program may fail.
950
951 @item --adjust-section-vma @var{section}@{=,+,-@}@var{val}
952 Set or adjust the address of the named @var{section}. If @samp{=} is
953 used, the section address is set to @var{val}. Otherwise, @var{val} is
954 added to or subtracted from the section address. See the comments under
955 @samp{--adjust-vma}, above. If @var{section} does not exist in the
956 input file, a warning will be issued, unless @samp{--no-adjust-warnings}
957 is used.
958
959 @item --adjust-warnings
960 If @samp{--adjust-section-vma} is used, and the named section does not
961 exist, issue a warning. This is the default.
962
963 @item --no-adjust-warnings
964 Do not issue a warning if @samp{--adjust-section-vma} is used, even if
965 the named section does not exist.
966
967 @item --set-section-flags @var{section}=@var{flags}
968 Set the flags for the named section. The @var{flags} argument is a
969 comma separated string of flag names. The recognized names are
970 @samp{alloc}, @samp{load}, @samp{readonly}, @samp{code}, @samp{data},
971 and @samp{rom}. Not all flags are meaningful for all object file
972 formats.
973
974 @item --add-section @var{sectionname}=@var{filename}
975 Add a new section named @var{sectionname} while copying the file. The
976 contents of the new section are taken from the file @var{filename}. The
977 size of the section will be the size of the file. This option only
978 works on file formats which can support sections with arbitrary names.
979
980 @item --remove-leading-char
981 If the first character of a global symbol is a special symbol leading
982 character used by the object file format, remove the character. The
983 most common symbol leading character is underscore. This option will
984 remove a leading underscore from all global symbols. This can be useful
985 if you want to link together objects of different file formats with
986 different conventions for symbol names.
987
988 @item -V
989 @itemx --version
990 Show the version number of @code{objcopy}.
991
992 @item -v
993 @itemx --verbose
994 Verbose output: list all object files modified. In the case of
995 archives, @samp{objcopy -V} lists all members of the archive.
996
997 @item --help
998 Show a summary of the options to @code{objcopy}.
999 @end table
1000
1001 @node objdump
1002 @chapter objdump
1003
1004 @cindex object file information
1005 @kindex objdump
1006
1007 @smallexample
1008 objdump [ -a | --archive-headers ]
1009 [ -b @var{bfdname} | --target=@var{bfdname} ] [ --debugging ]
1010 [ -d | --disassemble ] [ -D | --disassemble-all ]
1011 [ -f | --file-headers ]
1012 [ -h | --section-headers | --headers ] [ -i | --info ]
1013 [ -j @var{section} | --section=@var{section} ]
1014 [ -l | --line-numbers ] [ -S | --source ]
1015 [ -m @var{machine} | --architecture=@var{machine} ]
1016 [ -r | --reloc ] [ -R | --dynamic-reloc ]
1017 [ -s | --full-contents ] [ --stabs ]
1018 [ -t | --syms ] [ -T | --dynamic-syms ] [ -x | --all-headers ]
1019 [ -w | --wide ] [ --start-address=@var{address} ]
1020 [ --stop-address=@var{address} ] [ --show-raw-insn ]
1021 [ --version ] [ --help ]
1022 @var{objfile}@dots{}
1023 @end smallexample
1024
1025 @code{objdump} displays information about one or more object files.
1026 The options control what particular information to display. This
1027 information is mostly useful to programmers who are working on the
1028 compilation tools, as opposed to programmers who just want their
1029 program to compile and work.
1030
1031 @var{objfile}@dots{} are the object files to be examined. When you
1032 specify archives, @code{objdump} shows information on each of the member
1033 object files.
1034
1035 The long and short forms of options, shown here as alternatives, are
1036 equivalent. At least one option besides @samp{-l} must be given.
1037
1038 @table @code
1039 @item -a
1040 @itemx --archive-header
1041 @cindex archive headers
1042 If any of the @var{objfile} files are archives, display the archive
1043 header information (in a format similar to @samp{ls -l}). Besides the
1044 information you could list with @samp{ar tv}, @samp{objdump -a} shows
1045 the object file format of each archive member.
1046
1047 @item -b @var{bfdname}
1048 @itemx --target=@var{bfdname}
1049 @cindex object code format
1050 Specify that the object-code format for the object files is
1051 @var{bfdname}. This option may not be necessary; @var{objdump} can
1052 automatically recognize many formats.
1053
1054 For example,
1055 @example
1056 objdump -b oasys -m vax -h fu.o
1057 @end example
1058 @noindent
1059 displays summary information from the section headers (@samp{-h}) of
1060 @file{fu.o}, which is explicitly identified (@samp{-m}) as a VAX object
1061 file in the format produced by Oasys compilers. You can list the
1062 formats available with the @samp{-i} option.
1063 @xref{Target Selection}, for more information.
1064
1065 @item --debugging
1066 Display debugging information. This attempts to parse debugging
1067 information stored in the file and print it out using a C like syntax.
1068 Only certain types of debugging information have been implemented.
1069
1070 @item -d
1071 @itemx --disassemble
1072 @cindex disassembling object code
1073 @cindex machine instructions
1074 Display the assembler mnemonics for the machine instructions from
1075 @var{objfile}. This option only disassembles those sections which are
1076 expected to contain instructions.
1077
1078 @item -D
1079 @itemx --disassemble-all
1080 Like @samp{-d}, but disassemble the contents of all sections, not just
1081 those expected to contain instructions.
1082
1083 @item -f
1084 @itemx --file-header
1085 @cindex object file header
1086 Display summary information from the overall header of
1087 each of the @var{objfile} files.
1088
1089 @item -h
1090 @itemx --section-header
1091 @itemx --header
1092 @cindex section headers
1093 Display summary information from the section headers of the
1094 object file.
1095
1096 File segments may be relocated to nonstandard addresses, for example by
1097 using the @samp{-Ttext}, @samp{-Tdata}, or @samp{-Tbss} options to
1098 @code{ld}. However, some object file formats, such as a.out, do not
1099 store the starting address of the file segments. In those situations,
1100 although @code{ld} relocates the sections correctly, using @samp{objdump
1101 -h} to list the file section headers cannot show the correct addresses.
1102 Instead, it shows the usual addresses, which are implicit for the
1103 target.
1104
1105 @item --help
1106 Print a summary of the options to @code{objdump} and exit.
1107
1108 @item -i
1109 @itemx --info
1110 @cindex architectures available
1111 @cindex object formats available
1112 Display a list showing all architectures and object formats available
1113 for specification with @samp{-b} or @samp{-m}.
1114
1115 @item -j @var{name}
1116 @itemx --section=@var{name}
1117 @cindex section information
1118 Display information only for section @var{name}.
1119
1120 @item -l
1121 @itemx --line-numbers
1122 @cindex source filenames for object files
1123 Label the display (using debugging information) with the filename
1124 and source line numbers corresponding to the object code shown.
1125 Only useful with @samp{-d} or @samp{-D}.
1126
1127 @item -m @var{machine}
1128 @itemx --architecture=@var{machine}
1129 @cindex architecture
1130 Specify that the object files @var{objfile} are for architecture
1131 @var{machine}. You can list available architectures using the @samp{-i}
1132 option.
1133
1134 @item -r
1135 @itemx --reloc
1136 @cindex relocation entries, in object file
1137 Print the relocation entries of the file. If used with @samp{-d} or
1138 @samp{-D}, the relocations are printed interspersed with the
1139 disassembly.
1140
1141 @item -R
1142 @itemx --dynamic-reloc
1143 @cindex dynamic relocation entries, in object file
1144 Print the dynamic relocation entries of the file. This is only
1145 meaningful for dynamic objects, such as certain types of shared
1146 libraries.
1147
1148 @item -s
1149 @itemx --full-contents
1150 @cindex sections, full contents
1151 @cindex object file sections
1152 Display the full contents of any sections requested.
1153
1154 @item -S
1155 @itemx --source
1156 @cindex source disassembly
1157 @cindex disassembly, with source
1158 Display source code intermixed with disassembly, if possible. Implies
1159 @samp{-d}.
1160
1161 @item --show-raw-insn
1162 When disassembling instructions, print the instruction in hex as well as
1163 in symbolic form. Not all targets handle this correctly yet.
1164
1165 @item --stabs
1166 @cindex stab
1167 @cindex .stab
1168 @cindex debug symbols
1169 @cindex ELF object file format
1170 Display the full contents of any sections requested. Display the
1171 contents of the .stab and .stab.index and .stab.excl sections from an
1172 ELF file. This is only useful on systems (such as Solaris 2.0) in which
1173 @code{.stab} debugging symbol-table entries are carried in an ELF
1174 section. In most other file formats, debugging symbol-table entries are
1175 interleaved with linkage symbols, and are visible in the @samp{--syms}
1176 output. For more information on stabs symbols, see @ref{Top,Stabs,Stabs
1177 Overview,stabs.info, The ``stabs'' debug format}.
1178
1179 @item --start-address=@var{address}
1180 @cindex start-address
1181 Start displaying data at the specified address. This affects the output
1182 of the @code{-d}, @code{-r} and @code{-s} options.
1183
1184 @item --stop-address=@var{address}
1185 @cindex stop-address
1186 Stop displaying data at the specified address. This affects the output
1187 of the @code{-d}, @code{-r} and @code{-s} options.
1188
1189 @item -t
1190 @itemx --syms
1191 @cindex symbol table entries, printing
1192 Print the symbol table entries of the file.
1193 This is similar to the information provided by the @samp{nm} program.
1194
1195 @item -T
1196 @itemx --dynamic-syms
1197 @cindex dynamic symbol table entries, printing
1198 Print the dynamic symbol table entries of the file. This is only
1199 meaningful for dynamic objects, such as certain types of shared
1200 libraries. This is similar to the information provided by the @samp{nm}
1201 program when given the @samp{-D} (@samp{--dynamic}) option.
1202
1203 @item --version
1204 Print the version number of @code{objdump} and exit.
1205
1206 @item -x
1207 @itemx --all-header
1208 @cindex all header information, object file
1209 @cindex header information, all
1210 Display all available header information, including the symbol table and
1211 relocation entries. Using @samp{-x} is equivalent to specifying all of
1212 @samp{-a -f -h -r -t}.
1213
1214 @item -w
1215 @item --wide
1216 @cindex wide output, printing
1217 Format some lines for output devices that have more than 80 columns.
1218 @end table
1219
1220 @node ranlib
1221 @chapter ranlib
1222
1223 @kindex ranlib
1224 @cindex archive contents
1225 @cindex symbol index
1226
1227 @smallexample
1228 ranlib [-vV] @var{archive}
1229 @end smallexample
1230
1231 @code{ranlib} generates an index to the contents of an archive and
1232 stores it in the archive. The index lists each symbol defined by a
1233 member of an archive that is a relocatable object file.
1234
1235 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
1236
1237 An archive with such an index speeds up linking to the library and
1238 allows routines in the library to call each other without regard to
1239 their placement in the archive.
1240
1241 The @sc{gnu} @code{ranlib} program is another form of @sc{gnu} @code{ar}; running
1242 @code{ranlib} is completely equivalent to executing @samp{ar -s}.
1243 @xref{ar}.
1244
1245 @table @code
1246 @item -v
1247 @itemx -V
1248 Show the version number of @code{ranlib}.
1249 @end table
1250
1251 @node size
1252 @chapter size
1253
1254 @kindex size
1255 @cindex section sizes
1256
1257 @smallexample
1258 size [ -A | -B | --format=@var{compatibility} ]
1259 [ --help ] [ -d | -o | -x | --radix=@var{number} ]
1260 [ --target=@var{bfdname} ] [ -V | --version ]
1261 @var{objfile}@dots{}
1262 @end smallexample
1263
1264 The @sc{gnu} @code{size} utility lists the section sizes---and the total
1265 size---for each of the object or archive files @var{objfile} in its
1266 argument list. By default, one line of output is generated for each
1267 object file or each module in an archive.
1268
1269 @var{objfile}@dots{} are the object files to be examined.
1270
1271 The command line options have the following meanings:
1272
1273 @table @code
1274 @item -A
1275 @itemx -B
1276 @itemx --format=@var{compatibility}
1277 @cindex @code{size} display format
1278 Using one of these options, you can choose whether the output from @sc{gnu}
1279 @code{size} resembles output from System V @code{size} (using @samp{-A},
1280 or @samp{--format=sysv}), or Berkeley @code{size} (using @samp{-B}, or
1281 @samp{--format=berkeley}). The default is the one-line format similar to
1282 Berkeley's.
1283 @c Bonus for doc-source readers: you can also say --format=strange (or
1284 @c anything else that starts with 's') for sysv, and --format=boring (or
1285 @c anything else that starts with 'b') for Berkeley.
1286
1287 Here is an example of the Berkeley (default) format of output from
1288 @code{size}:
1289 @smallexample
1290 size --format=Berkeley ranlib size
1291 text data bss dec hex filename
1292 294880 81920 11592 388392 5ed28 ranlib
1293 294880 81920 11888 388688 5ee50 size
1294 @end smallexample
1295
1296 @noindent
1297 This is the same data, but displayed closer to System V conventions:
1298
1299 @smallexample
1300 size --format=SysV ranlib size
1301 ranlib :
1302 section size addr
1303 .text 294880 8192
1304 .data 81920 303104
1305 .bss 11592 385024
1306 Total 388392
1307
1308
1309 size :
1310 section size addr
1311 .text 294880 8192
1312 .data 81920 303104
1313 .bss 11888 385024
1314 Total 388688
1315 @end smallexample
1316
1317 @item --help
1318 Show a summary of acceptable arguments and options.
1319
1320 @item -d
1321 @itemx -o
1322 @itemx -x
1323 @itemx --radix=@var{number}
1324 @cindex @code{size} number format
1325 @cindex radix for section sizes
1326 Using one of these options, you can control whether the size of each
1327 section is given in decimal (@samp{-d}, or @samp{--radix=10}); octal
1328 (@samp{-o}, or @samp{--radix=8}); or hexadecimal (@samp{-x}, or
1329 @samp{--radix=16}). In @samp{--radix=@var{number}}, only the three
1330 values (8, 10, 16) are supported. The total size is always given in two
1331 radices; decimal and hexadecimal for @samp{-d} or @samp{-x} output, or
1332 octal and hexadecimal if you're using @samp{-o}.
1333
1334 @item --target=@var{bfdname}
1335 @cindex object code format
1336 Specify that the object-code format for @var{objfile} is
1337 @var{bfdname}. This option may not be necessary; @code{size} can
1338 automatically recognize many formats.
1339 @xref{Target Selection}, for more information.
1340
1341 @item -V
1342 @itemx --version
1343 Display the version number of @code{size}.
1344 @end table
1345
1346 @node strings
1347 @chapter strings
1348 @kindex strings
1349 @cindex listings strings
1350 @cindex printing strings
1351 @cindex strings, printing
1352
1353 @smallexample
1354 strings [-afov] [-@var{min-len}] [-n @var{min-len}] [-t @var{radix}] [-]
1355 [--all] [--print-file-name] [--bytes=@var{min-len}]
1356 [--radix=@var{radix}] [--target=@var{bfdname}]
1357 [--help] [--version] @var{file}@dots{}
1358 @end smallexample
1359
1360 For each @var{file} given, @sc{gnu} @code{strings} prints the printable
1361 character sequences that are at least 4 characters long (or the number
1362 given with the options below) and are followed by an unprintable
1363 character. By default, it only prints the strings from the initialized
1364 and loaded sections of object files; for other types of files, it prints
1365 the strings from the whole file.
1366
1367 @code{strings} is mainly useful for determining the contents of non-text
1368 files.
1369
1370 @table @code
1371 @item -a
1372 @itemx --all
1373 @itemx -
1374 Do not scan only the initialized and loaded sections of object files;
1375 scan the whole files.
1376
1377 @item -f
1378 @itemx --print-file-name
1379 Print the name of the file before each string.
1380
1381 @item --help
1382 Print a summary of the program usage on the standard output and exit.
1383
1384 @itemx -@var{min-len}
1385 @item -n @var{min-len}
1386 @itemx --bytes=@var{min-len}
1387 Print sequences of characters that are at least @var{min-len} characters
1388 long, instead of the default 4.
1389
1390 @item -o
1391 Like @samp{-t o}. Some other versions of @code{strings} have @samp{-o}
1392 act like @samp{-t d} instead. Since we can not be compatible with both
1393 ways, we simply chose one.
1394
1395 @item -t @var{radix}
1396 @itemx --radix=@var{radix}
1397 Print the offset within the file before each string. The single
1398 character argument specifies the radix of the offset---@samp{o} for
1399 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
1400
1401 @item --target=@var{bfdname}
1402 @cindex object code format
1403 Specify an object code format other than your system's default format.
1404 @xref{Target Selection}, for more information.
1405
1406 @item -v
1407 @itemx --version
1408 Print the program version number on the standard output and exit.
1409 @end table
1410
1411 @node strip
1412 @chapter strip
1413
1414 @kindex strip
1415 @cindex removing symbols
1416 @cindex discarding symbols
1417 @cindex symbols, discarding
1418
1419 @smallexample
1420 strip [ -F @var{bfdname} | --target=@var{bfdname} | --target=@var{bfdname} ]
1421 [ -I @var{bfdname} | --input-target=@var{bfdname} ]
1422 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
1423 [ -s | --strip-all ] [ -S | -g | --strip-debug ]
1424 [ -K @var{symbolname} | --keep-symbol=@var{symbolname} ]
1425 [ -N @var{symbolname} | --strip-symbol=@var{symbolname} ]
1426 [ -x | --discard-all ] [ -X | --discard-locals ]
1427 [ -R @var{sectionname} | --remove-section=@var{sectionname} ]
1428 [ -v | --verbose ] [ -V | --version ] [ --help ]
1429 @var{objfile}@dots{}
1430 @end smallexample
1431
1432 @sc{gnu} @code{strip} discards all symbols from object files
1433 @var{objfile}. The list of object files may include archives.
1434 At least one object file must be given.
1435
1436 @code{strip} modifies the files named in its argument,
1437 rather than writing modified copies under different names.
1438
1439 @table @code
1440 @item -F @var{bfdname}
1441 @itemx --target=@var{bfdname}
1442 Treat the original @var{objfile} as a file with the object
1443 code format @var{bfdname}, and rewrite it in the same format.
1444 @xref{Target Selection}, for more information.
1445
1446 @item --help
1447 Show a summary of the options to @code{strip} and exit.
1448
1449 @item -I @var{bfdname}
1450 @itemx --input-target=@var{bfdname}
1451 Treat the original @var{objfile} as a file with the object
1452 code format @var{bfdname}.
1453 @xref{Target Selection}, for more information.
1454
1455 @item -O @var{bfdname}
1456 @itemx --output-target=@var{bfdname}
1457 Replace @var{objfile} with a file in the output format @var{bfdname}.
1458 @xref{Target Selection}, for more information.
1459
1460 @item -R @var{sectionname}
1461 @itemx --remove-section=@var{sectionname}
1462 Remove any section named @var{sectionname} from the output file. This
1463 option may be given more than once. Note that using this option
1464 inappropriately may make the output file unusable.
1465
1466 @item -s
1467 @itemx --strip-all
1468 Remove all symbols.
1469
1470 @item -g
1471 @itemx -S
1472 @itemx --strip-debug
1473 Remove debugging symbols only.
1474
1475 @item --strip-unneeded
1476 Remove all symbols that are not needed for relocation processing.
1477
1478 @item -K @var{symbolname}
1479 @itemx --keep-symbol=@var{symbolname}
1480 Keep only symbol @var{symbolname} from the source file. This option may
1481 be given more than once.
1482
1483 @item -N @var{symbolname}
1484 @itemx --strip-symbol=@var{symbolname}
1485 Remove symbol @var{symbolname} from the source file. This option may be
1486 given more than once, and may be combined with strip options other than
1487 @code{-K}.
1488
1489 @item -x
1490 @itemx --discard-all
1491 Remove non-global symbols.
1492
1493 @item -X
1494 @itemx --discard-locals
1495 Remove compiler-generated local symbols.
1496 (These usually start with @samp{L} or @samp{.}.)
1497
1498 @item -V
1499 @itemx --version
1500 Show the version number for @code{strip}.
1501
1502 @item -v
1503 @itemx --verbose
1504 Verbose output: list all object files modified. In the case of
1505 archives, @samp{strip -v} lists all members of the archive.
1506 @end table
1507
1508 @node c++filt
1509 @chapter c++filt
1510
1511 @kindex c++filt
1512 @cindex demangling C++ symbols
1513
1514 @smallexample
1515 c++filt [ -_ | --strip-underscores ]
1516 [ -n | --no-strip-underscores ]
1517 [ -s @var{format} | --format=@var{format} ]
1518 [ --help ] [ --version ] [ @var{symbol}@dots{} ]
1519 @end smallexample
1520
1521 The C++ language provides function overloading, which means that you can
1522 write many functions with the same name (providing each takes parameters
1523 of different types). All C++ function names are encoded into a
1524 low-level assembly label (this process is known as
1525 @dfn{mangling}). The @code{c++filt} program does the inverse mapping: it
1526 decodes (@dfn{demangles}) low-level names into user-level names so that
1527 the linker can keep these overloaded functions from clashing.
1528
1529 Every alphanumeric word (consisting of letters, digits, underscores,
1530 dollars, or periods) seen in the input is a potential label. If the
1531 label decodes into a C++ name, the C++ name replaces the low-level
1532 name in the output.
1533
1534 You can use @code{c++filt} to decipher individual symbols:
1535
1536 @example
1537 c++filt @var{symbol}
1538 @end example
1539
1540 If no @var{symbol} arguments are given, @code{c++filt} reads symbol
1541 names from the standard input and writes the demangled names to the
1542 standard output. All results are printed on the standard output.
1543
1544 @table @code
1545 @item -_
1546 @itemx --strip-underscores
1547 On some systems, both the C and C++ compilers put an underscore in front
1548 of every name. For example, the C name @code{foo} gets the low-level
1549 name @code{_foo}. This option removes the initial underscore. Whether
1550 @code{c++filt} removes the underscore by default is target dependent.
1551
1552 @item -n
1553 @itemx --no-strip-underscores
1554 Do not remove the initial underscore.
1555
1556 @item -s @var{format}
1557 @itemx --format=@var{format}
1558 @sc{gnu} @code{nm} can decode three different methods of mangling, used by
1559 different C++ compilers. The argument to this option selects which
1560 method it uses:
1561
1562 @table @code
1563 @item gnu
1564 the one used by the @sc{gnu} compiler (the default method)
1565 @item lucid
1566 the one used by the Lucid compiler
1567 @item arm
1568 the one specified by the C++ Annotated Reference Manual
1569 @end table
1570
1571 @item --help
1572 Print a summary of the options to @code{c++filt} and exit.
1573
1574 @item --version
1575 Print the version number of @code{c++filt} and exit.
1576 @end table
1577
1578 @quotation
1579 @emph{Warning:} @code{c++filt} is a new utility, and the details of its
1580 user interface are subject to change in future releases. In particular,
1581 a command-line option may be required in the the future to decode a name
1582 passed as an argument on the command line; in other words,
1583
1584 @example
1585 c++filt @var{symbol}
1586 @end example
1587
1588 @noindent
1589 may in a future release become
1590
1591 @example
1592 c++filt @var{option} @var{symbol}
1593 @end example
1594 @end quotation
1595
1596 @node nlmconv
1597 @chapter nlmconv
1598
1599 @code{nlmconv} converts a relocatable object file into a NetWare
1600 Loadable Module.
1601
1602 @ignore
1603 @code{nlmconv} currently works with @samp{i386} object
1604 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
1605 object files in @sc{elf}, or @code{a.out} format@footnote{
1606 @code{nlmconv} should work with any @samp{i386} or @sc{sparc} object
1607 format in the Binary File Descriptor library. It has only been tested
1608 with the above formats.}.
1609 @end ignore
1610
1611 @quotation
1612 @emph{Warning:} @code{nlmconv} is not always built as part of the binary
1613 utilities, since it is only useful for NLM targets.
1614 @end quotation
1615
1616 @smallexample
1617 nlmconv [ -I @var{bfdname} | --input-target=@var{bfdname} ]
1618 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
1619 [ -T @var{headerfile} | --header-file=@var{headerfile} ]
1620 [ -d | --debug] [ -l @var{linker} | --linker=@var{linker} ]
1621 [ -h | --help ] [ -V | --version ]
1622 @var{infile} @var{outfile}
1623 @end smallexample
1624
1625 @code{nlmconv} converts the relocatable @samp{i386} object file
1626 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
1627 reading @var{headerfile} for NLM header information. For instructions
1628 on writing the NLM command file language used in header files, see the
1629 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
1630 Development and Tools Overview}, which is part of the NLM Software
1631 Developer's Kit (``NLM SDK''), available from Novell, Inc.
1632 @code{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
1633 @var{infile}; see @ref{BFD,,BFD,ld.info,Using LD}, for
1634 more information.
1635
1636 @code{nlmconv} can perform a link step. In other words, you can list
1637 more than one object file for input if you list them in the definitions
1638 file (rather than simply specifying one input file on the command line).
1639 In this case, @code{nlmconv} calls the linker for you.
1640
1641 @table @code
1642 @item -I @var{bfdname}
1643 @itemx --input-target=@var{bfdname}
1644 Object format of the input file. @code{nlmconv} can usually determine
1645 the format of a given file (so no default is necessary).
1646 @xref{Target Selection}, for more information.
1647
1648 @item -O @var{bfdname}
1649 @itemx --output-target=@var{bfdname}
1650 Object format of the output file. @code{nlmconv} infers the output
1651 format based on the input format, e.g. for a @samp{i386} input file the
1652 output format is @samp{nlm32-i386}.
1653 @xref{Target Selection}, for more information.
1654
1655 @item -T @var{headerfile}
1656 @itemx --header-file=@var{headerfile}
1657 Reads @var{headerfile} for NLM header information. For instructions on
1658 writing the NLM command file language used in header files, see@ see the
1659 @samp{linkers} section, of the @cite{NLM Development and Tools
1660 Overview}, which is part of the NLM Software Developer's Kit, available
1661 from Novell, Inc.
1662
1663 @item -d
1664 @itemx --debug
1665 Displays (on standard error) the linker command line used by @code{nlmconv}.
1666
1667 @item -l @var{linker}
1668 @itemx --linker=@var{linker}
1669 Use @var{linker} for any linking. @var{linker} can be an abosolute or a
1670 relative pathname.
1671
1672 @item -h
1673 @itemx --help
1674 Prints a usage summary.
1675
1676 @item -V
1677 @itemx --version
1678 Prints the version number for @code{nlmconv}.
1679 @end table
1680
1681 @node Selecting The Target System
1682 @chapter Selecting the target system
1683
1684 You can specify three aspects of the target system to the @sc{gnu}
1685 binary file utilities, each in several ways:
1686
1687 @itemize @bullet
1688 @item
1689 the target
1690
1691 @item
1692 the architecture
1693
1694 @item
1695 the linker emulation (which applies to the linker only)
1696 @end itemize
1697
1698 In the following summaries, the lists of ways to specify values are in
1699 order of decreasing precedence. The ways listed first override those
1700 listed later.
1701
1702 The commands to list valid values only list the values for which the
1703 programs you are running were configured. If they were configured with
1704 @samp{--enable-targets=all}, the commands list most of the available
1705 values, but a few are left out; not all targets can be configured in at
1706 once because some of them can only be configured @dfn{native} (on hosts
1707 with the same type as the target system).
1708
1709 @menu
1710 * Target Selection::
1711 * Architecture Selection::
1712 * Linker Emulation Selection::
1713 @end menu
1714
1715 @node Target Selection
1716 @section Target Selection
1717
1718 A @dfn{target} is an object file format. A given target may be
1719 supported for multiple architectures (@pxref{Architecture Selection}).
1720 A target selection may also have variations for different operating
1721 systems or architectures.
1722
1723 The command to list valid target values is @samp{objdump -i}
1724 (the first column of output contains the relevant information).
1725
1726 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
1727 @samp{a.out-sunos-big}.
1728
1729 @subheading @code{objdump} Target
1730
1731 Ways to specify:
1732
1733 @enumerate
1734 @item
1735 command line option: @samp{-b} or @samp{--target}
1736
1737 @item
1738 environment variable @code{GNUTARGET}
1739
1740 @item
1741 deduced from the input file
1742 @end enumerate
1743
1744 @subheading @code{objcopy} and @code{strip} Input Target
1745
1746 Ways to specify:
1747
1748 @enumerate
1749 @item
1750 command line options: @samp{-I} or @samp{--input-target}, or @samp{-F} or @samp{--target}
1751
1752 @item
1753 environment variable @code{GNUTARGET}
1754
1755 @item
1756 deduced from the input file
1757 @end enumerate
1758
1759 @subheading @code{objcopy} and @code{strip} Output Target
1760
1761 Ways to specify:
1762
1763 @enumerate
1764 @item
1765 command line options: @samp{-O} or @samp{--output-target}, or @samp{-F} or @samp{--target}
1766
1767 @item
1768 the input target (see ``@code{objcopy} and @code{strip} Input Target'' above)
1769
1770 @item
1771 environment variable @code{GNUTARGET}
1772
1773 @item
1774 deduced from the input file
1775 @end enumerate
1776
1777 @subheading @code{nm}, @code{size}, and @code{strings} Target
1778
1779 Ways to specify:
1780
1781 @enumerate
1782 @item
1783 command line option: @samp{--target}
1784
1785 @item
1786 environment variable @code{GNUTARGET}
1787
1788 @item
1789 deduced from the input file
1790 @end enumerate
1791
1792 @subheading Linker Input Target
1793
1794 Ways to specify:
1795
1796 @enumerate
1797 @item
1798 command line option: @samp{-b} or @samp{--format}
1799 (@pxref{Options,,Options,ld.info,Using LD})
1800
1801 @item
1802 script command @code{TARGET}
1803 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
1804
1805 @item
1806 environment variable @code{GNUTARGET}
1807 (@pxref{Environment,,Environment,ld.info,Using LD})
1808
1809 @item
1810 the default target of the selected linker emulation
1811 (@pxref{Linker Emulation Selection})
1812 @end enumerate
1813
1814 @subheading Linker Output Target
1815
1816 Ways to specify:
1817
1818 @enumerate
1819 @item
1820 command line option: @samp{-oformat}
1821 (@pxref{Options,,Options,ld.info,Using LD})
1822
1823 @item
1824 script command @code{OUTPUT_FORMAT}
1825 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
1826
1827 @item
1828 the linker input target (see ``Linker Input Target'' above)
1829 @end enumerate
1830
1831 @node Architecture Selection
1832 @section Architecture selection
1833
1834 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
1835 to run. Its name may contain a colon, separating the name of the
1836 processor family from the name of the particular @sc{cpu}.
1837
1838 The command to list valid architecture values is @samp{objdump -i} (the
1839 second column contains the relevant information).
1840
1841 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
1842
1843 @subheading @code{objdump} Architecture
1844
1845 Ways to specify:
1846
1847 @enumerate
1848 @item
1849 command line option: @samp{-m} or @samp{--architecture}
1850
1851 @item
1852 deduced from the input file
1853 @end enumerate
1854
1855 @subheading @code{objcopy}, @code{nm}, @code{size}, @code{strings} Architecture
1856
1857 Ways to specify:
1858
1859 @enumerate
1860 @item
1861 deduced from the input file
1862 @end enumerate
1863
1864 @subheading Linker Input Architecture
1865
1866 Ways to specify:
1867
1868 @enumerate
1869 @item
1870 deduced from the input file
1871 @end enumerate
1872
1873 @subheading Linker Output Architecture
1874
1875 Ways to specify:
1876
1877 @enumerate
1878 @item
1879 script command @code{OUTPUT_ARCH}
1880 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
1881
1882 @item
1883 the default architecture from the linker output target
1884 (@pxref{Target Selection})
1885 @end enumerate
1886
1887 @node Linker Emulation Selection
1888 @section Linker emulation selection
1889
1890 A linker @dfn{emulation} is a ``personality'' of the linker, which gives
1891 the linker default values for the other aspects of the target system.
1892 In particular, it consists of
1893
1894 @itemize @bullet
1895 @item
1896 the linker script
1897
1898 @item
1899 the target
1900
1901 @item
1902 several ``hook'' functions that are run at certain stages of the linking
1903 process to do special things that some targets require
1904 @end itemize
1905
1906 The command to list valid linker emulation values is @samp{ld -V}.
1907
1908 Sample values: @samp{hp300bsd}, @samp{mipslit}, @samp{sun4}.
1909
1910 Ways to specify:
1911
1912 @enumerate
1913 @item
1914 command line option: @samp{-m}
1915 (@pxref{Options,,Options,ld.info,Using LD})
1916
1917 @item
1918 environment variable @code{LDEMULATION}
1919
1920 @item
1921 compiled-in @code{DEFAULT_EMULATION} from @file{Makefile},
1922 which comes from @code{EMUL} in @file{config/@var{target}.mt}
1923 @end enumerate
1924
1925 @node Index
1926 @unnumbered Index
1927
1928 @printindex cp
1929
1930 @contents
1931 @bye