1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
8 * Binutils: (binutils). The GNU binary utilities.
9 * ar: (binutils)ar. Create, modify, and extract from archives
10 * nm: (binutils)nm. List symbols from object files
11 * objcopy: (binutils)objcopy. Copy and translate object files
12 * objdump: (binutils)objdump. Display information from object files
13 * ranlib: (binutils)ranlib. Generate index to archive contents
14 * readelf: (binutils)readelf. Display the contents of ELF format files.
15 * size: (binutils)size. List section sizes and total size
16 * strings: (binutils)strings. List printable strings from files
17 * strip: (binutils)strip. Discard symbols
18 * c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols
19 * cxxfilt: (binutils)c++filt. MS-DOS name for c++filt
20 * addr2line: (binutils)addr2line. Convert addresses to file and line
21 * nlmconv: (binutils)nlmconv. Converts object code into an NLM
22 * windres: (binutils)windres. Manipulate Windows resources
23 * dlltool: (binutils)dlltool. Create files needed to build and use DLLs
29 Copyright @copyright{} 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000 Free Software Foundation, Inc.
31 Permission is granted to make and distribute verbatim copies of
32 this manual provided the copyright notice and this permission notice
33 are preserved on all copies.
36 Permission is granted to process this file through TeX and print the
37 results, provided the printed document carries a copying permission
38 notice identical to this one except for the removal of this paragraph
39 (this paragraph not being relevant to the printed manual).
43 Permission is granted to copy and distribute modified versions of this
44 manual under the conditions for verbatim copying, provided also that
45 the entire resulting derived work is distributed under the terms of a
46 permission notice identical to this one.
48 Permission is granted to copy and distribute translations of this manual
49 into another language, under the above conditions for modified versions.
54 @c This file documents the GNU binary utilities "ar", "ld", "objcopy",
55 @c "objdump", "nm", "size", "strings", "strip", "readelf" and "ranlib".
57 @c Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000 Free Software Foundation, Inc.
59 @c This text may be freely distributed under the terms of the GNU
60 @c General Public License.
63 @setchapternewpage odd
64 @settitle @sc{gnu} Binary Utilities
67 @title The @sc{gnu} Binary Utilities
68 @subtitle Version @value{VERSION}
71 @author Roland H. Pesch
72 @author Jeffrey M. Osier
73 @author Cygnus Support
77 {\parskip=0pt \hfill Cygnus Support\par \hfill
78 \TeX{}info \texinfoversion\par }
81 @vskip 0pt plus 1filll
82 Copyright @copyright{} 1991, 92, 93, 94, 95, 96, 97, 1998 Free Software Foundation, Inc.
84 Permission is granted to make and distribute verbatim copies of
85 this manual provided the copyright notice and this permission notice
86 are preserved on all copies.
88 Permission is granted to copy and distribute modified versions of this
89 manual under the conditions for verbatim copying, provided also that
90 the entire resulting derived work is distributed under the terms of a
91 permission notice identical to this one.
93 Permission is granted to copy and distribute translations of this manual
94 into another language, under the above conditions for modified versions.
101 This brief manual contains preliminary documentation for the @sc{gnu} binary
102 utilities (collectively version @value{VERSION}):
107 Create, modify, and extract from archives
110 List symbols from object files
113 Copy and translate object files
116 Display information from object files
119 Generate index to archive contents
122 Display the contents of ELF format files.
125 List file section sizes and total size
128 List printable strings from files
134 Demangle encoded C++ symbols (on MS-DOS, this program is named
138 Convert addresses into file names and line numbers
141 Convert object code into a Netware Loadable Module
144 Manipulate Windows resources
147 Create the files needed to build and use Dynamic Link Libraries
152 * ar:: Create, modify, and extract from archives
153 * nm:: List symbols from object files
154 * objcopy:: Copy and translate object files
155 * objdump:: Display information from object files
156 * ranlib:: Generate index to archive contents
157 * readelf:: Display the contents of ELF format files.
158 * size:: List section sizes and total size
159 * strings:: List printable strings from files
160 * strip:: Discard symbols
161 * c++filt:: Filter to demangle encoded C++ symbols
162 * cxxfilt: c++filt. MS-DOS name for c++filt
163 * addr2line:: Convert addresses to file and line
164 * nlmconv:: Converts object code into an NLM
165 * windres:: Manipulate Windows resources
166 * dlltool:: Create files needed to build and use DLLs
167 * Selecting The Target System:: How these utilities determine the target.
168 * Reporting Bugs:: Reporting Bugs
177 @cindex collections of files
179 ar [-]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
180 ar -M [ <mri-script ]
183 The @sc{gnu} @code{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).
188 The original files' contents, mode (permissions), timestamp, owner, and
189 group are preserved in the archive, and can be restored on
193 @sc{gnu} @code{ar} can maintain archives whose members have names of any
194 length; however, depending on how @code{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).
201 @code{ar} is considered a binary utility because archives of this sort
202 are most often used as @dfn{libraries} holding commonly needed
206 @code{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 @code{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.
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 @code{ar} called
216 @code{ranlib} can be used to add just the table.
218 @cindex compatibility, @code{ar}
219 @cindex @code{ar} compatibility
220 @sc{gnu} @code{ar} is designed to be compatible with two different
221 facilities. You can control its activity using command-line options,
222 like the different varieties of @code{ar} on Unix systems; or, if you
223 specify the single command-line option @samp{-M}, you can control it
224 with a script supplied via standard input, like the MRI ``librarian''
228 * ar cmdline:: Controlling @code{ar} on the command line
229 * ar scripts:: Controlling @code{ar} with a script
234 @section Controlling @code{ar} on the command line
237 ar [-]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
240 @cindex Unix compatibility, @code{ar}
241 When you use @code{ar} in the Unix style, @code{ar} insists on at least two
242 arguments to execute: one keyletter specifying the @emph{operation}
243 (optionally accompanied by other keyletters specifying
244 @emph{modifiers}), and the archive name to act on.
246 Most operations can also accept further @var{member} arguments,
247 specifying particular files to operate on.
249 @sc{gnu} @code{ar} allows you to mix the operation code @var{p} and modifier
250 flags @var{mod} in any order, within the first command-line argument.
252 If you wish, you may begin the first command-line argument with a
255 @cindex operations on archive
256 The @var{p} keyletter specifies what operation to execute; it may be
257 any of the following, but you must specify only one of them:
261 @cindex deleting from archive
262 @emph{Delete} modules from the archive. Specify the names of modules to
263 be deleted as @var{member}@dots{}; the archive is untouched if you
264 specify no files to delete.
266 If you specify the @samp{v} modifier, @code{ar} lists each module
270 @cindex moving in archive
271 Use this operation to @emph{move} members in an archive.
273 The ordering of members in an archive can make a difference in how
274 programs are linked using the library, if a symbol is defined in more
277 If no modifiers are used with @code{m}, any members you name in the
278 @var{member} arguments are moved to the @emph{end} of the archive;
279 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
280 specified place instead.
283 @cindex printing from archive
284 @emph{Print} the specified members of the archive, to the standard
285 output file. If the @samp{v} modifier is specified, show the member
286 name before copying its contents to standard output.
288 If you specify no @var{member} arguments, all the files in the archive are
292 @cindex quick append to archive
293 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
294 @var{archive}, without checking for replacement.
296 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
297 operation; new members are always placed at the end of the archive.
299 The modifier @samp{v} makes @code{ar} list each file as it is appended.
301 Since the point of this operation is speed, the archive's symbol table
302 index is not updated, even if it already existed; you can use @samp{ar s} or
303 @code{ranlib} explicitly to update the symbol table index.
305 However, too many different systems assume quick append rebuilds the
306 index, so GNU ar implements @code{q} as a synonym for @code{r}.
309 @cindex replacement in archive
310 Insert the files @var{member}@dots{} into @var{archive} (with
311 @emph{replacement}). This operation differs from @samp{q} in that any
312 previously existing members are deleted if their names match those being
315 If one of the files named in @var{member}@dots{} does not exist, @code{ar}
316 displays an error message, and leaves undisturbed any existing members
317 of the archive matching that name.
319 By default, new members are added at the end of the file; but you may
320 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
321 placement relative to some existing member.
323 The modifier @samp{v} used with this operation elicits a line of
324 output for each file inserted, along with one of the letters @samp{a} or
325 @samp{r} to indicate whether the file was appended (no old member
326 deleted) or replaced.
329 @cindex contents of archive
330 Display a @emph{table} listing the contents of @var{archive}, or those
331 of the files listed in @var{member}@dots{} that are present in the
332 archive. Normally only the member name is shown; if you also want to
333 see the modes (permissions), timestamp, owner, group, and size, you can
334 request that by also specifying the @samp{v} modifier.
336 If you do not specify a @var{member}, all files in the archive
339 @cindex repeated names in archive
340 @cindex name duplication in archive
341 If there is more than one file with the same name (say, @samp{fie}) in
342 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
343 first instance; to see them all, you must ask for a complete
344 listing---in our example, @samp{ar t b.a}.
345 @c WRS only; per Gumby, this is implementation-dependent, and in a more
346 @c recent case in fact works the other way.
349 @cindex extract from archive
350 @emph{Extract} members (named @var{member}) from the archive. You can
351 use the @samp{v} modifier with this operation, to request that
352 @code{ar} list each name as it extracts it.
354 If you do not specify a @var{member}, all files in the archive
359 A number of modifiers (@var{mod}) may immediately follow the @var{p}
360 keyletter, to specify variations on an operation's behavior:
364 @cindex relative placement in archive
365 Add new files @emph{after} an existing member of the
366 archive. If you use the modifier @samp{a}, the name of an existing archive
367 member must be present as the @var{relpos} argument, before the
368 @var{archive} specification.
371 Add new files @emph{before} an existing member of the
372 archive. If you use the modifier @samp{b}, the name of an existing archive
373 member must be present as the @var{relpos} argument, before the
374 @var{archive} specification. (same as @samp{i}).
377 @cindex creating archives
378 @emph{Create} the archive. The specified @var{archive} is always
379 created if it did not exist, when you request an update. But a warning is
380 issued unless you specify in advance that you expect to create it, by
384 Truncate names in the archive. @sc{gnu} @code{ar} will normally permit file
385 names of any length. This will cause it to create archives which are
386 not compatible with the native @code{ar} program on some systems. If
387 this is a concern, the @samp{f} modifier may be used to truncate file
388 names when putting them in the archive.
391 Insert new files @emph{before} an existing member of the
392 archive. If you use the modifier @samp{i}, the name of an existing archive
393 member must be present as the @var{relpos} argument, before the
394 @var{archive} specification. (same as @samp{b}).
397 This modifier is accepted but not used.
398 @c whaffor ar l modifier??? presumably compat; with
399 @c what???---doc@@cygnus.com, 25jan91
402 Uses the @var{count} parameter. This is used if there are multiple
403 entries in the archive with the same name. Extract or delete instance
404 @var{count} of the given name from the archive.
407 @cindex dates in archive
408 Preserve the @emph{original} dates of members when extracting them. If
409 you do not specify this modifier, files extracted from the archive
410 are stamped with the time of extraction.
413 Use the full path name when matching names in the archive. @sc{gnu}
414 @code{ar} can not create an archive with a full path name (such archives
415 are not POSIX complaint), but other archive creators can. This option
416 will cause @sc{gnu} @code{ar} to match file names using a complete path
417 name, which can be convenient when extracting a single file from an
418 archive created by another tool.
421 @cindex writing archive index
422 Write an object-file index into the archive, or update an existing one,
423 even if no other change is made to the archive. You may use this modifier
424 flag either with any operation, or alone. Running @samp{ar s} on an
425 archive is equivalent to running @samp{ranlib} on it.
428 @cindex not writing archive index
429 Do not generate an archive symbol table. This can speed up building a
430 large library in several steps. The resulting archive can not be used
431 with the linker. In order to build a symbol table, you must omit the
432 @samp{S} modifier on the last execution of @samp{ar}, or you must run
433 @samp{ranlib} on the archive.
436 @cindex updating an archive
437 Normally, @samp{ar r}@dots{} inserts all files
438 listed into the archive. If you would like to insert @emph{only} those
439 of the files you list that are newer than existing members of the same
440 names, use this modifier. The @samp{u} modifier is allowed only for the
441 operation @samp{r} (replace). In particular, the combination @samp{qu} is
442 not allowed, since checking the timestamps would lose any speed
443 advantage from the operation @samp{q}.
446 This modifier requests the @emph{verbose} version of an operation. Many
447 operations display additional information, such as filenames processed,
448 when the modifier @samp{v} is appended.
451 This modifier shows the version number of @code{ar}.
455 @section Controlling @code{ar} with a script
458 ar -M [ <@var{script} ]
461 @cindex MRI compatibility, @code{ar}
462 @cindex scripts, @code{ar}
463 If you use the single command-line option @samp{-M} with @code{ar}, you
464 can control its operation with a rudimentary command language. This
465 form of @code{ar} operates interactively if standard input is coming
466 directly from a terminal. During interactive use, @code{ar} prompts for
467 input (the prompt is @samp{AR >}), and continues executing even after
468 errors. If you redirect standard input to a script file, no prompts are
469 issued, and @code{ar} abandons execution (with a nonzero exit code)
472 The @code{ar} command language is @emph{not} designed to be equivalent
473 to the command-line options; in fact, it provides somewhat less control
474 over archives. The only purpose of the command language is to ease the
475 transition to @sc{gnu} @code{ar} for developers who already have scripts
476 written for the MRI ``librarian'' program.
478 The syntax for the @code{ar} command language is straightforward:
481 commands are recognized in upper or lower case; for example, @code{LIST}
482 is the same as @code{list}. In the following descriptions, commands are
483 shown in upper case for clarity.
486 a single command may appear on each line; it is the first word on the
490 empty lines are allowed, and have no effect.
493 comments are allowed; text after either of the characters @samp{*}
494 or @samp{;} is ignored.
497 Whenever you use a list of names as part of the argument to an @code{ar}
498 command, you can separate the individual names with either commas or
499 blanks. Commas are shown in the explanations below, for clarity.
502 @samp{+} is used as a line continuation character; if @samp{+} appears
503 at the end of a line, the text on the following line is considered part
504 of the current command.
507 Here are the commands you can use in @code{ar} scripts, or when using
508 @code{ar} interactively. Three of them have special significance:
510 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
511 a temporary file required for most of the other commands.
513 @code{SAVE} commits the changes so far specified by the script. Prior
514 to @code{SAVE}, commands affect only the temporary copy of the current
518 @item ADDLIB @var{archive}
519 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
520 Add all the contents of @var{archive} (or, if specified, each named
521 @var{module} from @var{archive}) to the current archive.
523 Requires prior use of @code{OPEN} or @code{CREATE}.
525 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
526 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
527 @c else like "ar q..."
528 Add each named @var{member} as a module in the current archive.
530 Requires prior use of @code{OPEN} or @code{CREATE}.
533 Discard the contents of the current archive, canceling the effect of
534 any operations since the last @code{SAVE}. May be executed (with no
535 effect) even if no current archive is specified.
537 @item CREATE @var{archive}
538 Creates an archive, and makes it the current archive (required for many
539 other commands). The new archive is created with a temporary name; it
540 is not actually saved as @var{archive} until you use @code{SAVE}.
541 You can overwrite existing archives; similarly, the contents of any
542 existing file named @var{archive} will not be destroyed until @code{SAVE}.
544 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
545 Delete each listed @var{module} from the current archive; equivalent to
546 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
548 Requires prior use of @code{OPEN} or @code{CREATE}.
550 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
551 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
552 List each named @var{module} present in @var{archive}. The separate
553 command @code{VERBOSE} specifies the form of the output: when verbose
554 output is off, output is like that of @samp{ar -t @var{archive}
555 @var{module}@dots{}}. When verbose output is on, the listing is like
556 @samp{ar -tv @var{archive} @var{module}@dots{}}.
558 Output normally goes to the standard output stream; however, if you
559 specify @var{outputfile} as a final argument, @code{ar} directs the
563 Exit from @code{ar}, with a @code{0} exit code to indicate successful
564 completion. This command does not save the output file; if you have
565 changed the current archive since the last @code{SAVE} command, those
568 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
569 Extract each named @var{module} from the current archive, writing them
570 into the current directory as separate files. Equivalent to @samp{ar -x
571 @var{archive} @var{module}@dots{}}.
573 Requires prior use of @code{OPEN} or @code{CREATE}.
576 @c FIXME Tokens but no commands???
583 Display full contents of the current archive, in ``verbose'' style
584 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
585 tv @var{archive}}. (This single command is a @sc{gnu} @code{ar}
586 enhancement, rather than present for MRI compatibility.)
588 Requires prior use of @code{OPEN} or @code{CREATE}.
590 @item OPEN @var{archive}
591 Opens an existing archive for use as the current archive (required for
592 many other commands). Any changes as the result of subsequent commands
593 will not actually affect @var{archive} until you next use @code{SAVE}.
595 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
596 In the current archive, replace each existing @var{module} (named in
597 the @code{REPLACE} arguments) from files in the current working directory.
598 To execute this command without errors, both the file, and the module in
599 the current archive, must exist.
601 Requires prior use of @code{OPEN} or @code{CREATE}.
604 Toggle an internal flag governing the output from @code{DIRECTORY}.
605 When the flag is on, @code{DIRECTORY} output matches output from
606 @samp{ar -tv }@dots{}.
609 Commit your changes to the current archive, and actually save it as a
610 file with the name specified in the last @code{CREATE} or @code{OPEN}
613 Requires prior use of @code{OPEN} or @code{CREATE}.
622 The @sc{gnu} linker @code{ld} is now described in a separate manual.
623 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
632 nm [ -a | --debug-syms ] [ -g | --extern-only ]
633 [ -B ] [ -C | --demangle ] [ -D | --dynamic ]
634 [ -s | --print-armap ] [ -A | -o | --print-file-name ]
635 [ -n | -v | --numeric-sort ] [ -p | --no-sort ]
636 [ -r | --reverse-sort ] [ --size-sort ] [ -u | --undefined-only ]
637 [ -t @var{radix} | --radix=@var{radix} ] [ -P | --portability ]
638 [ --target=@var{bfdname} ] [ -f @var{format} | --format=@var{format} ]
639 [ --defined-only ] [-l | --line-numbers ]
640 [ --no-demangle ] [ -V | --version ] [ --help ] [ @var{objfile}@dots{} ]
643 @sc{gnu} @code{nm} lists the symbols from object files @var{objfile}@dots{}.
644 If no object files are listed as arguments, @code{nm} assumes the file
647 For each symbol, @code{nm} shows:
651 The symbol value, in the radix selected by options (see below), or
652 hexadecimal by default.
655 The symbol type. At least the following types are used; others are, as
656 well, depending on the object file format. If lowercase, the symbol is
657 local; if uppercase, the symbol is global (external).
659 @c Some more detail on exactly what these symbol types are used for
663 The symbol's value is absolute, and will not be changed by further
667 The symbol is in the uninitialized data section (known as BSS).
670 The symbol is common. Common symbols are uninitialized data. When
671 linking, multiple common symbols may appear with the same name. If the
672 symbol is defined anywhere, the common symbols are treated as undefined
673 references. For more details on common symbols, see the discussion of
674 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
677 The symbol is in the initialized data section.
680 The symbol is in an initialized data section for small objects. Some
681 object file formats permit more efficient access to small data objects,
682 such as a global int variable as opposed to a large global array.
685 The symbol is an indirect reference to another symbol. This is a GNU
686 extension to the a.out object file format which is rarely used.
689 The symbol is a debugging symbol.
692 The symbol is in a read only data section.
695 The symbol is in an uninitialized data section for small objects.
698 The symbol is in the text (code) section.
701 The symbol is undefined.
704 The symbol is weak. When a weak defined symbol is linked with a normal
705 defined symbol, the normal defined symbol is used with no error. When a
706 weak undefined symbol is linked and the symbol is not defined, the value
707 of the weak symbol becomes zero with no error.
710 The symbol is a stabs symbol in an a.out object file. In this case, the
711 next values printed are the stabs other field, the stabs desc field, and
712 the stab type. Stabs symbols are used to hold debugging information;
713 for more information, see @ref{Top,Stabs,Stabs Overview,stabs.info, The
714 ``stabs'' debug format}.
717 The symbol type is unknown, or object file format specific.
724 The long and short forms of options, shown here as alternatives, are
730 @itemx --print-file-name
731 @cindex input file name
733 @cindex source file name
734 Precede each symbol by the name of the input file (or archive member)
735 in which it was found, rather than identifying the input file once only,
736 before all of its symbols.
740 @cindex debugging symbols
741 Display all symbols, even debugger-only symbols; normally these are not
745 @cindex @code{nm} format
746 @cindex @code{nm} compatibility
747 The same as @samp{--format=bsd} (for compatibility with the MIPS @code{nm}).
751 @cindex demangling in nm
752 Decode (@dfn{demangle}) low-level symbol names into user-level names.
753 Besides removing any initial underscore prepended by the system, this
754 makes C++ function names readable. @xref{c++filt}, for more information
758 Do not demangle low-level symbol names. This is the default.
762 @cindex dynamic symbols
763 Display the dynamic symbols rather than the normal symbols. This is
764 only meaningful for dynamic objects, such as certain types of shared
767 @item -f @var{format}
768 @itemx --format=@var{format}
769 @cindex @code{nm} format
770 @cindex @code{nm} compatibility
771 Use the output format @var{format}, which can be @code{bsd},
772 @code{sysv}, or @code{posix}. The default is @code{bsd}.
773 Only the first character of @var{format} is significant; it can be
774 either upper or lower case.
778 @cindex external symbols
779 Display only external symbols.
782 @itemx --line-numbers
783 @cindex symbol line numbers
784 For each symbol, use debugging information to try to find a filename and
785 line number. For a defined symbol, look for the line number of the
786 address of the symbol. For an undefined symbol, look for the line
787 number of a relocation entry which refers to the symbol. If line number
788 information can be found, print it after the other symbol information.
792 @itemx --numeric-sort
793 Sort symbols numerically by their addresses, rather than alphabetically
798 @cindex sorting symbols
799 Do not bother to sort the symbols in any order; print them in the order
804 Use the POSIX.2 standard output format instead of the default format.
805 Equivalent to @samp{-f posix}.
809 @cindex symbol index, listing
810 When listing symbols from archive members, include the index: a mapping
811 (stored in the archive by @code{ar} or @code{ranlib}) of which modules
812 contain definitions for which names.
815 @itemx --reverse-sort
816 Reverse the order of the sort (whether numeric or alphabetic); let the
820 Sort symbols by size. The size is computed as the difference between
821 the value of the symbol and the value of the symbol with the next higher
822 value. The size of the symbol is printed, rather than the value.
825 @itemx --radix=@var{radix}
826 Use @var{radix} as the radix for printing the symbol values. It must be
827 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
829 @item --target=@var{bfdname}
830 @cindex object code format
831 Specify an object code format other than your system's default format.
832 @xref{Target Selection}, for more information.
835 @itemx --undefined-only
836 @cindex external symbols
837 @cindex undefined symbols
838 Display only undefined symbols (those external to each object file).
841 @cindex external symbols
842 @cindex undefined symbols
843 Display only defined symbols for each object file.
847 Show the version number of @code{nm} and exit.
850 Show a summary of the options to @code{nm} and exit.
857 objcopy [ -F @var{bfdname} | --target=@var{bfdname} ]
858 [ -I @var{bfdname} | --input-target=@var{bfdname} ]
859 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
860 [ -S | --strip-all ] [ -g | --strip-debug ]
861 [ -K @var{symbolname} | --keep-symbol=@var{symbolname} ]
862 [ -N @var{symbolname} | --strip-symbol=@var{symbolname} ]
863 [ -L @var{symbolname} | --localize-symbol=@var{symbolname} ]
864 [ -W @var{symbolname} | --weaken-symbol=@var{symbolname} ]
865 [ -x | --discard-all ] [ -X | --discard-locals ]
866 [ -b @var{byte} | --byte=@var{byte} ]
867 [ -i @var{interleave} | --interleave=@var{interleave} ]
868 [ -j @var{sectionname} | --only-section=@var{sectionname} ]
869 [ -R @var{sectionname} | --remove-section=@var{sectionname} ]
870 [ -p | --preserve-dates ] [ --debugging ]
871 [ --gap-fill=@var{val} ] [ --pad-to=@var{address} ]
872 [ --set-start=@var{val} ] [ --adjust-start=@var{incr} ]
873 [ --change-addresses=@var{incr} ]
874 [ --change-section-address=@var{section}@{=,+,-@}@var{val} ]
875 [ --change-section-lma=@var{section}@{=,+,-@}@var{val} ]
876 [ --change-section-vma=@var{section}@{=,+,-@}@var{val} ]
877 [ --change-warnings ] [ --no-change-warnings ]
878 [ --set-section-flags=@var{section}=@var{flags} ]
879 [ --add-section=@var{sectionname}=@var{filename} ]
880 [ --change-leading-char ] [ --remove-leading-char ]
882 [ -v | --verbose ] [ -V | --version ] [ --help ]
883 @var{infile} [@var{outfile}]
886 The @sc{gnu} @code{objcopy} utility copies the contents of an object
887 file to another. @code{objcopy} uses the @sc{gnu} @sc{bfd} Library to
888 read and write the object files. It can write the destination object
889 file in a format different from that of the source object file. The
890 exact behavior of @code{objcopy} is controlled by command-line options.
892 @code{objcopy} creates temporary files to do its translations and
893 deletes them afterward. @code{objcopy} uses @sc{bfd} to do all its
894 translation work; it has access to all the formats described in @sc{bfd}
895 and thus is able to recognize most formats without being told
896 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
898 @code{objcopy} can be used to generate S-records by using an output
899 target of @samp{srec} (e.g., use @samp{-O srec}).
901 @code{objcopy} can be used to generate a raw binary file by using an
902 output target of @samp{binary} (e.g., use @samp{-O binary}). When
903 @code{objcopy} generates a raw binary file, it will essentially produce
904 a memory dump of the contents of the input object file. All symbols and
905 relocation information will be discarded. The memory dump will start at
906 the load address of the lowest section copied into the output file.
908 When generating an S-record or a raw binary file, it may be helpful to
909 use @samp{-S} to remove sections containing debugging information. In
910 some cases @samp{-R} will be useful to remove sections which contain
911 information that is not needed by the binary file.
916 The input and output files, respectively.
917 If you do not specify @var{outfile}, @code{objcopy} creates a
918 temporary file and destructively renames the result with
919 the name of @var{infile}.
921 @item -I @var{bfdname}
922 @itemx --input-target=@var{bfdname}
923 Consider the source file's object format to be @var{bfdname}, rather than
924 attempting to deduce it. @xref{Target Selection}, for more information.
926 @item -O @var{bfdname}
927 @itemx --output-target=@var{bfdname}
928 Write the output file using the object format @var{bfdname}.
929 @xref{Target Selection}, for more information.
931 @item -F @var{bfdname}
932 @itemx --target=@var{bfdname}
933 Use @var{bfdname} as the object format for both the input and the output
934 file; i.e., simply transfer data from source to destination with no
935 translation. @xref{Target Selection}, for more information.
937 @item -j @var{sectionname}
938 @itemx --only-section=@var{sectionname}
939 Copy only the named section from the input file to the output file.
940 This option may be given more than once. Note that using this option
941 inappropriately may make the output file unusable.
943 @item -R @var{sectionname}
944 @itemx --remove-section=@var{sectionname}
945 Remove any section named @var{sectionname} from the output file. This
946 option may be given more than once. Note that using this option
947 inappropriately may make the output file unusable.
951 Do not copy relocation and symbol information from the source file.
955 Do not copy debugging symbols from the source file.
957 @item --strip-unneeded
958 Strip all symbols that are not needed for relocation processing.
960 @item -K @var{symbolname}
961 @itemx --keep-symbol=@var{symbolname}
962 Copy only symbol @var{symbolname} from the source file. This option may
963 be given more than once.
965 @item -N @var{symbolname}
966 @itemx --strip-symbol=@var{symbolname}
967 Do not copy symbol @var{symbolname} from the source file. This option
968 may be given more than once.
970 @item -L @var{symbolname}
971 @itemx --localize-symbol=@var{symbolname}
972 Make symbol @var{symbolname} local to the file, so that it is not
973 visible externally. This option may be given more than once.
975 @item -W @var{symbolname}
976 @itemx --weaken-symbol=@var{symbolname}
977 Make symbol @var{symbolname} weak. This option may be given more than once.
981 Do not copy non-global symbols from the source file.
982 @c FIXME any reason to prefer "non-global" to "local" here?
985 @itemx --discard-locals
986 Do not copy compiler-generated local symbols.
987 (These usually start with @samp{L} or @samp{.}.)
990 @itemx --byte=@var{byte}
991 Keep only every @var{byte}th byte of the input file (header data is not
992 affected). @var{byte} can be in the range from 0 to @var{interleave}-1,
993 where @var{interleave} is given by the @samp{-i} or @samp{--interleave}
994 option, or the default of 4. This option is useful for creating files
995 to program @sc{rom}. It is typically used with an @code{srec} output
998 @item -i @var{interleave}
999 @itemx --interleave=@var{interleave}
1000 Only copy one out of every @var{interleave} bytes. Select which byte to
1001 copy with the @var{-b} or @samp{--byte} option. The default is 4.
1002 @code{objcopy} ignores this option if you do not specify either @samp{-b} or
1006 @itemx --preserve-dates
1007 Set the access and modification dates of the output file to be the same
1008 as those of the input file.
1011 Convert debugging information, if possible. This is not the default
1012 because only certain debugging formats are supported, and the
1013 conversion process can be time consuming.
1015 @item --gap-fill @var{val}
1016 Fill gaps between sections with @var{val}. This operation applies to
1017 the @emph{load address} (LMA) of the sections. It is done by increasing
1018 the size of the section with the lower address, and filling in the extra
1019 space created with @var{val}.
1021 @item --pad-to @var{address}
1022 Pad the output file up to the load address @var{address}. This is
1023 done by increasing the size of the last section. The extra space is
1024 filled in with the value specified by @samp{--gap-fill} (default zero).
1026 @item --set-start @var{val}
1027 Set the start address of the new file to @var{val}. Not all object file
1028 formats support setting the start address.
1030 @item --change-start @var{incr}
1031 @itemx --adjust-start @var{incr}
1032 @cindex changing start address
1033 Change the start address by adding @var{incr}. Not all object file
1034 formats support setting the start address.
1036 @item --change-addresses @var{incr}
1037 @itemx --adjust-vma @var{incr}
1038 @cindex changing object addresses
1039 Change the VMA and LMA addresses of all sections, as well as the start
1040 address, by adding @var{incr}. Some object file formats do not permit
1041 section addresses to be changed arbitrarily. Note that this does not
1042 relocate the sections; if the program expects sections to be loaded at a
1043 certain address, and this option is used to change the sections such
1044 that they are loaded at a different address, the program may fail.
1046 @item --change-section-address @var{section}@{=,+,-@}@var{val}
1047 @itemx --adjust-section-vma @var{section}@{=,+,-@}@var{val}
1048 @cindex changing section address
1049 Set or change both the VMA address and the LMA address of the named
1050 @var{section}. If @samp{=} is used, the section address is set to
1051 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1052 section address. See the comments under @samp{--change-addresses},
1053 above. If @var{section} does not exist in the input file, a warning will
1054 be issued, unless @samp{--no-change-warnings} is used.
1056 @item --change-section-lma @var{section}@{=,+,-@}@var{val}
1057 @cindex changing section LMA
1058 Set or change the LMA address of the named @var{section}. The LMA
1059 address is the address where the section will be loaded into memory at
1060 program load time. Normally this is the same as the VMA address, which
1061 is the address of the section at program run time, but on some systems,
1062 especially those where a program is held in ROM, the two can be
1063 different. If @samp{=} is used, the section address is set to
1064 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1065 section address. See the comments under @samp{--change-addresses},
1066 above. If @var{section} does not exist in the input file, a warning
1067 will be issued, unless @samp{--no-change-warnings} is used.
1069 @item --change-section-vma @var{section}@{=,+,-@}@var{val}
1070 @cindex changing section VMA
1071 Set or change the VMA address of the named @var{section}. The VMA
1072 address is the address where the section will be located once the
1073 program has started executing. Normally this is the same as the LMA
1074 address, which is the address where the section will be loaded into
1075 memory, but on some systems, especially those where a program is held in
1076 ROM, the two can be different. If @samp{=} is used, the section address
1077 is set to @var{val}. Otherwise, @var{val} is added to or subtracted
1078 from the section address. See the comments under
1079 @samp{--change-addresses}, above. If @var{section} does not exist in
1080 the input file, a warning will be issued, unless
1081 @samp{--no-change-warnings} is used.
1083 @item --change-warnings
1084 @itemx --adjust-warnings
1085 If @samp{--change-section-address} or @samp{--change-section-lma} or
1086 @samp{--change-section-vma} is used, and the named section does not
1087 exist, issue a warning. This is the default.
1089 @item --no-change-warnings
1090 @itemx --no-adjust-warnings
1091 Do not issue a warning if @samp{--change-section-address} or
1092 @samp{--adjust-section-lma} or @samp{--adjust-section-vma} is used, even
1093 if the named section does not exist.
1095 @item --set-section-flags @var{section}=@var{flags}
1096 Set the flags for the named section. The @var{flags} argument is a
1097 comma separated string of flag names. The recognized names are
1098 @samp{alloc}, @samp{contents}, @samp{load}, @samp{noload},
1099 @samp{readonly}, @samp{code}, @samp{data}, @samp{rom}, @samp{share}, and
1100 @samp{debug}. You can set the @samp{contents} flag for a section which
1101 does not have contents, but it is not meaningful to clear the
1102 @samp{contents} flag of a section which does have contents--just remove
1103 the section instead. Not all flags are meaningful for all object file
1106 @item --add-section @var{sectionname}=@var{filename}
1107 Add a new section named @var{sectionname} while copying the file. The
1108 contents of the new section are taken from the file @var{filename}. The
1109 size of the section will be the size of the file. This option only
1110 works on file formats which can support sections with arbitrary names.
1112 @item --change-leading-char
1113 Some object file formats use special characters at the start of
1114 symbols. The most common such character is underscore, which compilers
1115 often add before every symbol. This option tells @code{objcopy} to
1116 change the leading character of every symbol when it converts between
1117 object file formats. If the object file formats use the same leading
1118 character, this option has no effect. Otherwise, it will add a
1119 character, or remove a character, or change a character, as
1122 @item --remove-leading-char
1123 If the first character of a global symbol is a special symbol leading
1124 character used by the object file format, remove the character. The
1125 most common symbol leading character is underscore. This option will
1126 remove a leading underscore from all global symbols. This can be useful
1127 if you want to link together objects of different file formats with
1128 different conventions for symbol names. This is different from
1129 @code{--change-leading-char} because it always changes the symbol name
1130 when appropriate, regardless of the object file format of the output
1134 Change all global symbols in the file to be weak. This can be useful
1135 when building an object which will be linked against other objects using
1136 the @code{-R} option to the linker. This option is only effective when
1137 using an object file format which supports weak symbols.
1141 Show the version number of @code{objcopy}.
1145 Verbose output: list all object files modified. In the case of
1146 archives, @samp{objcopy -V} lists all members of the archive.
1149 Show a summary of the options to @code{objcopy}.
1155 @cindex object file information
1159 objdump [ -a | --archive-headers ]
1160 [ -b @var{bfdname} | --target=@var{bfdname} ]
1162 [ -d | --disassemble ]
1163 [ -D | --disassemble-all ]
1164 [ -z | --disassemble-zeroes ]
1165 [ -EB | -EL | --endian=@{big | little @} ]
1166 [ -f | --file-headers ]
1167 [ -g | --debugging ]
1168 [ -h | --section-headers | --headers ]
1170 [ -j @var{section} | --section=@var{section} ]
1171 [ -l | --line-numbers ]
1173 [ -m @var{machine} | --architecture=@var{machine} ]
1174 [ -M @var{options} | --disassembler-options=@var{options}]
1175 [ -p | --private-headers ]
1177 [ -R | --dynamic-reloc ]
1178 [ -s | --full-contents ]
1181 [ -T | --dynamic-syms ]
1182 [ -x | --all-headers ]
1184 [ --start-address=@var{address} ]
1185 [ --stop-address=@var{address} ]
1186 [ --prefix-addresses]
1187 [ --[no-]show-raw-insn ]
1188 [ --adjust-vma=@var{offset} ]
1191 @var{objfile}@dots{}
1194 @code{objdump} displays information about one or more object files.
1195 The options control what particular information to display. This
1196 information is mostly useful to programmers who are working on the
1197 compilation tools, as opposed to programmers who just want their
1198 program to compile and work.
1200 @var{objfile}@dots{} are the object files to be examined. When you
1201 specify archives, @code{objdump} shows information on each of the member
1204 The long and short forms of options, shown here as alternatives, are
1205 equivalent. At least one option from the list
1206 @samp{-a,-d,-D,-f,-g,-G,-h,-H,-p,-r,-R,-S,-t,-T,-V,-x} must be given.
1210 @itemx --archive-header
1211 @cindex archive headers
1212 If any of the @var{objfile} files are archives, display the archive
1213 header information (in a format similar to @samp{ls -l}). Besides the
1214 information you could list with @samp{ar tv}, @samp{objdump -a} shows
1215 the object file format of each archive member.
1217 @item --adjust-vma=@var{offset}
1218 @cindex section addresses in objdump
1219 @cindex VMA in objdump
1220 When dumping information, first add @var{offset} to all the section
1221 addresses. This is useful if the section addresses do not correspond to
1222 the symbol table, which can happen when putting sections at particular
1223 addresses when using a format which can not represent section addresses,
1226 @item -b @var{bfdname}
1227 @itemx --target=@var{bfdname}
1228 @cindex object code format
1229 Specify that the object-code format for the object files is
1230 @var{bfdname}. This option may not be necessary; @var{objdump} can
1231 automatically recognize many formats.
1235 objdump -b oasys -m vax -h fu.o
1238 displays summary information from the section headers (@samp{-h}) of
1239 @file{fu.o}, which is explicitly identified (@samp{-m}) as a VAX object
1240 file in the format produced by Oasys compilers. You can list the
1241 formats available with the @samp{-i} option.
1242 @xref{Target Selection}, for more information.
1246 @cindex demangling in objdump
1247 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1248 Besides removing any initial underscore prepended by the system, this
1249 makes C++ function names readable. @xref{c++filt}, for more information
1254 Display debugging information. This attempts to parse debugging
1255 information stored in the file and print it out using a C like syntax.
1256 Only certain types of debugging information have been implemented.
1259 @itemx --disassemble
1260 @cindex disassembling object code
1261 @cindex machine instructions
1262 Display the assembler mnemonics for the machine instructions from
1263 @var{objfile}. This option only disassembles those sections which are
1264 expected to contain instructions.
1267 @itemx --disassemble-all
1268 Like @samp{-d}, but disassemble the contents of all sections, not just
1269 those expected to contain instructions.
1271 @item --prefix-addresses
1272 When disassembling, print the complete address on each line. This is
1273 the older disassembly format.
1275 @item --disassemble-zeroes
1276 Normally the disassembly output will skip blocks of zeroes. This
1277 option directs the disassembler to disassemble those blocks, just like
1282 @itemx --endian=@{big|little@}
1284 @cindex disassembly endianness
1285 Specify the endianness of the object files. This only affects
1286 disassembly. This can be useful when disassembling a file format which
1287 does not describe endianness information, such as S-records.
1290 @itemx --file-header
1291 @cindex object file header
1292 Display summary information from the overall header of
1293 each of the @var{objfile} files.
1296 @itemx --section-header
1298 @cindex section headers
1299 Display summary information from the section headers of the
1302 File segments may be relocated to nonstandard addresses, for example by
1303 using the @samp{-Ttext}, @samp{-Tdata}, or @samp{-Tbss} options to
1304 @code{ld}. However, some object file formats, such as a.out, do not
1305 store the starting address of the file segments. In those situations,
1306 although @code{ld} relocates the sections correctly, using @samp{objdump
1307 -h} to list the file section headers cannot show the correct addresses.
1308 Instead, it shows the usual addresses, which are implicit for the
1312 Print a summary of the options to @code{objdump} and exit.
1316 @cindex architectures available
1317 @cindex object formats available
1318 Display a list showing all architectures and object formats available
1319 for specification with @samp{-b} or @samp{-m}.
1322 @itemx --section=@var{name}
1323 @cindex section information
1324 Display information only for section @var{name}.
1327 @itemx --line-numbers
1328 @cindex source filenames for object files
1329 Label the display (using debugging information) with the filename and
1330 source line numbers corresponding to the object code or relocs shown.
1331 Only useful with @samp{-d}, @samp{-D}, or @samp{-r}.
1333 @item -m @var{machine}
1334 @itemx --architecture=@var{machine}
1335 @cindex architecture
1336 @cindex disassembly architecture
1337 Specify the architecture to use when disassembling object files. This
1338 can be useful when disassembling object files which do not describe
1339 architecture information, such as S-records. You can list the available
1340 architectures with the @samp{-i} option.
1342 @item -M @var{options}
1343 @itemx --disassembler-options=@var{options}
1344 Pass target specific information to the disassembler. Only supported on
1347 If the target is an ARM architecture then this switch can be used to
1348 select which register name set is used during disassembler. Specifying
1349 @samp{-M reg-name-std} (the default) will select the register names as
1350 used in ARM's instruction set documentation, but with register 13 called
1351 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
1352 @samp{-M reg-names-apcs} will select the name set used by the ARM
1353 Procedure Call Standard, whilst specifying @samp{-M reg-names-raw} will
1354 just use @samp{r} followed by the register number.
1356 There are also two variants on the APCS register naming scheme enabled
1357 by @samp{-M reg-names-atpcs} and @samp{-M reg-names-atpcs-special} which
1358 use the ARM/Thumb Procedure Call Standard naming conventions. (Eiuther
1359 with the normal register name sor the special register names).
1361 This option can also be used for ARM architectures to force the
1362 disassembler to interpret all instructions as THUMB instructions by
1363 using the switch @samp{--disassembler-options=force-thumb}. This can be
1364 useful when attempting to disassemble thumb code produced by other
1368 @itemx --private-headers
1369 Print information that is specific to the object file format. The exact
1370 information printed depends upon the object file format. For some
1371 object file formats, no additional information is printed.
1375 @cindex relocation entries, in object file
1376 Print the relocation entries of the file. If used with @samp{-d} or
1377 @samp{-D}, the relocations are printed interspersed with the
1381 @itemx --dynamic-reloc
1382 @cindex dynamic relocation entries, in object file
1383 Print the dynamic relocation entries of the file. This is only
1384 meaningful for dynamic objects, such as certain types of shared
1388 @itemx --full-contents
1389 @cindex sections, full contents
1390 @cindex object file sections
1391 Display the full contents of any sections requested.
1395 @cindex source disassembly
1396 @cindex disassembly, with source
1397 Display source code intermixed with disassembly, if possible. Implies
1400 @item --show-raw-insn
1401 When disassembling instructions, print the instruction in hex as well as
1402 in symbolic form. This is the default except when
1403 @code{--prefix-addresses} is used.
1405 @item --no-show-raw-insn
1406 When disassembling instructions, do not print the instruction bytes.
1407 This is the default when @code{--prefix-addresses} is used.
1413 @cindex debug symbols
1414 @cindex ELF object file format
1415 Display the full contents of any sections requested. Display the
1416 contents of the .stab and .stab.index and .stab.excl sections from an
1417 ELF file. This is only useful on systems (such as Solaris 2.0) in which
1418 @code{.stab} debugging symbol-table entries are carried in an ELF
1419 section. In most other file formats, debugging symbol-table entries are
1420 interleaved with linkage symbols, and are visible in the @samp{--syms}
1421 output. For more information on stabs symbols, see @ref{Top,Stabs,Stabs
1422 Overview,stabs.info, The ``stabs'' debug format}.
1424 @item --start-address=@var{address}
1425 @cindex start-address
1426 Start displaying data at the specified address. This affects the output
1427 of the @code{-d}, @code{-r} and @code{-s} options.
1429 @item --stop-address=@var{address}
1430 @cindex stop-address
1431 Stop displaying data at the specified address. This affects the output
1432 of the @code{-d}, @code{-r} and @code{-s} options.
1436 @cindex symbol table entries, printing
1437 Print the symbol table entries of the file.
1438 This is similar to the information provided by the @samp{nm} program.
1441 @itemx --dynamic-syms
1442 @cindex dynamic symbol table entries, printing
1443 Print the dynamic symbol table entries of the file. This is only
1444 meaningful for dynamic objects, such as certain types of shared
1445 libraries. This is similar to the information provided by the @samp{nm}
1446 program when given the @samp{-D} (@samp{--dynamic}) option.
1449 Print the version number of @code{objdump} and exit.
1453 @cindex all header information, object file
1454 @cindex header information, all
1455 Display all available header information, including the symbol table and
1456 relocation entries. Using @samp{-x} is equivalent to specifying all of
1457 @samp{-a -f -h -r -t}.
1461 @cindex wide output, printing
1462 Format some lines for output devices that have more than 80 columns.
1469 @cindex archive contents
1470 @cindex symbol index
1473 ranlib [-vV] @var{archive}
1476 @code{ranlib} generates an index to the contents of an archive and
1477 stores it in the archive. The index lists each symbol defined by a
1478 member of an archive that is a relocatable object file.
1480 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
1482 An archive with such an index speeds up linking to the library and
1483 allows routines in the library to call each other without regard to
1484 their placement in the archive.
1486 The @sc{gnu} @code{ranlib} program is another form of @sc{gnu} @code{ar}; running
1487 @code{ranlib} is completely equivalent to executing @samp{ar -s}.
1494 Show the version number of @code{ranlib}.
1501 @cindex section sizes
1504 size [ -A | -B | --format=@var{compatibility} ]
1505 [ --help ] [ -d | -o | -x | --radix=@var{number} ]
1506 [ --target=@var{bfdname} ] [ -V | --version ]
1507 [ @var{objfile}@dots{} ]
1510 The @sc{gnu} @code{size} utility lists the section sizes---and the total
1511 size---for each of the object or archive files @var{objfile} in its
1512 argument list. By default, one line of output is generated for each
1513 object file or each module in an archive.
1515 @var{objfile}@dots{} are the object files to be examined.
1516 If none are specified, the file @code{a.out} will be used.
1518 The command line options have the following meanings:
1523 @itemx --format=@var{compatibility}
1524 @cindex @code{size} display format
1525 Using one of these options, you can choose whether the output from @sc{gnu}
1526 @code{size} resembles output from System V @code{size} (using @samp{-A},
1527 or @samp{--format=sysv}), or Berkeley @code{size} (using @samp{-B}, or
1528 @samp{--format=berkeley}). The default is the one-line format similar to
1530 @c Bonus for doc-source readers: you can also say --format=strange (or
1531 @c anything else that starts with 's') for sysv, and --format=boring (or
1532 @c anything else that starts with 'b') for Berkeley.
1534 Here is an example of the Berkeley (default) format of output from
1537 $ size --format=Berkeley ranlib size
1538 text data bss dec hex filename
1539 294880 81920 11592 388392 5ed28 ranlib
1540 294880 81920 11888 388688 5ee50 size
1544 This is the same data, but displayed closer to System V conventions:
1547 $ size --format=SysV ranlib size
1565 Show a summary of acceptable arguments and options.
1570 @itemx --radix=@var{number}
1571 @cindex @code{size} number format
1572 @cindex radix for section sizes
1573 Using one of these options, you can control whether the size of each
1574 section is given in decimal (@samp{-d}, or @samp{--radix=10}); octal
1575 (@samp{-o}, or @samp{--radix=8}); or hexadecimal (@samp{-x}, or
1576 @samp{--radix=16}). In @samp{--radix=@var{number}}, only the three
1577 values (8, 10, 16) are supported. The total size is always given in two
1578 radices; decimal and hexadecimal for @samp{-d} or @samp{-x} output, or
1579 octal and hexadecimal if you're using @samp{-o}.
1581 @item --target=@var{bfdname}
1582 @cindex object code format
1583 Specify that the object-code format for @var{objfile} is
1584 @var{bfdname}. This option may not be necessary; @code{size} can
1585 automatically recognize many formats.
1586 @xref{Target Selection}, for more information.
1590 Display the version number of @code{size}.
1596 @cindex listings strings
1597 @cindex printing strings
1598 @cindex strings, printing
1601 strings [-afov] [-@var{min-len}] [-n @var{min-len}] [-t @var{radix}] [-]
1602 [--all] [--print-file-name] [--bytes=@var{min-len}]
1603 [--radix=@var{radix}] [--target=@var{bfdname}]
1604 [--help] [--version] @var{file}@dots{}
1607 For each @var{file} given, @sc{gnu} @code{strings} prints the printable
1608 character sequences that are at least 4 characters long (or the number
1609 given with the options below) and are followed by an unprintable
1610 character. By default, it only prints the strings from the initialized
1611 and loaded sections of object files; for other types of files, it prints
1612 the strings from the whole file.
1614 @code{strings} is mainly useful for determining the contents of non-text
1621 Do not scan only the initialized and loaded sections of object files;
1622 scan the whole files.
1625 @itemx --print-file-name
1626 Print the name of the file before each string.
1629 Print a summary of the program usage on the standard output and exit.
1631 @item -@var{min-len}
1632 @itemx -n @var{min-len}
1633 @itemx --bytes=@var{min-len}
1634 Print sequences of characters that are at least @var{min-len} characters
1635 long, instead of the default 4.
1638 Like @samp{-t o}. Some other versions of @code{strings} have @samp{-o}
1639 act like @samp{-t d} instead. Since we can not be compatible with both
1640 ways, we simply chose one.
1642 @item -t @var{radix}
1643 @itemx --radix=@var{radix}
1644 Print the offset within the file before each string. The single
1645 character argument specifies the radix of the offset---@samp{o} for
1646 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
1648 @item --target=@var{bfdname}
1649 @cindex object code format
1650 Specify an object code format other than your system's default format.
1651 @xref{Target Selection}, for more information.
1655 Print the program version number on the standard output and exit.
1662 @cindex removing symbols
1663 @cindex discarding symbols
1664 @cindex symbols, discarding
1667 strip [ -F @var{bfdname} | --target=@var{bfdname} ]
1668 [ -I @var{bfdname} | --input-target=@var{bfdname} ]
1669 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
1670 [ -s | --strip-all ] [ -S | -g | --strip-debug ]
1671 [ -K @var{symbolname} | --keep-symbol=@var{symbolname} ]
1672 [ -N @var{symbolname} | --strip-symbol=@var{symbolname} ]
1673 [ -x | --discard-all ] [ -X | --discard-locals ]
1674 [ -R @var{sectionname} | --remove-section=@var{sectionname} ]
1675 [ -o @var{file} ] [ -p | --preserve-dates ]
1676 [ -v | --verbose ] [ -V | --version ] [ --help ]
1677 @var{objfile}@dots{}
1680 @sc{gnu} @code{strip} discards all symbols from object files
1681 @var{objfile}. The list of object files may include archives.
1682 At least one object file must be given.
1684 @code{strip} modifies the files named in its argument,
1685 rather than writing modified copies under different names.
1688 @item -F @var{bfdname}
1689 @itemx --target=@var{bfdname}
1690 Treat the original @var{objfile} as a file with the object
1691 code format @var{bfdname}, and rewrite it in the same format.
1692 @xref{Target Selection}, for more information.
1695 Show a summary of the options to @code{strip} and exit.
1697 @item -I @var{bfdname}
1698 @itemx --input-target=@var{bfdname}
1699 Treat the original @var{objfile} as a file with the object
1700 code format @var{bfdname}.
1701 @xref{Target Selection}, for more information.
1703 @item -O @var{bfdname}
1704 @itemx --output-target=@var{bfdname}
1705 Replace @var{objfile} with a file in the output format @var{bfdname}.
1706 @xref{Target Selection}, for more information.
1708 @item -R @var{sectionname}
1709 @itemx --remove-section=@var{sectionname}
1710 Remove any section named @var{sectionname} from the output file. This
1711 option may be given more than once. Note that using this option
1712 inappropriately may make the output file unusable.
1720 @itemx --strip-debug
1721 Remove debugging symbols only.
1723 @item --strip-unneeded
1724 Remove all symbols that are not needed for relocation processing.
1726 @item -K @var{symbolname}
1727 @itemx --keep-symbol=@var{symbolname}
1728 Keep only symbol @var{symbolname} from the source file. This option may
1729 be given more than once.
1731 @item -N @var{symbolname}
1732 @itemx --strip-symbol=@var{symbolname}
1733 Remove symbol @var{symbolname} from the source file. This option may be
1734 given more than once, and may be combined with strip options other than
1738 Put the stripped output in @var{file}, rather than replacing the
1739 existing file. When this argument is used, only one @var{objfile}
1740 argument may be specified.
1743 @itemx --preserve-dates
1744 Preserve the access and modification dates of the file.
1747 @itemx --discard-all
1748 Remove non-global symbols.
1751 @itemx --discard-locals
1752 Remove compiler-generated local symbols.
1753 (These usually start with @samp{L} or @samp{.}.)
1757 Show the version number for @code{strip}.
1761 Verbose output: list all object files modified. In the case of
1762 archives, @samp{strip -v} lists all members of the archive.
1765 @node c++filt, addr2line, strip, Top
1769 @cindex demangling C++ symbols
1772 c++filt [ -_ | --strip-underscores ]
1774 [ -n | --no-strip-underscores ]
1775 [ -s @var{format} | --format=@var{format} ]
1776 [ --help ] [ --version ] [ @var{symbol}@dots{} ]
1780 The C++ and Java languages provides function overloading, which means
1781 that you can write many functions with the same name (providing each
1782 takes parameters of different types). All C++ and Java function names
1783 are encoded into a low-level assembly label (this process is known as
1784 @dfn{mangling}). The @code{c++filt}
1785 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
1786 MS-DOS this program is named @code{cxxfilt}.}
1787 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
1788 names into user-level names so that the linker can keep these overloaded
1789 functions from clashing.
1791 Every alphanumeric word (consisting of letters, digits, underscores,
1792 dollars, or periods) seen in the input is a potential label. If the
1793 label decodes into a C++ name, the C++ name replaces the low-level
1796 You can use @code{c++filt} to decipher individual symbols:
1799 c++filt @var{symbol}
1802 If no @var{symbol} arguments are given, @code{c++filt} reads symbol
1803 names from the standard input and writes the demangled names to the
1804 standard output. All results are printed on the standard output.
1808 @itemx --strip-underscores
1809 On some systems, both the C and C++ compilers put an underscore in front
1810 of every name. For example, the C name @code{foo} gets the low-level
1811 name @code{_foo}. This option removes the initial underscore. Whether
1812 @code{c++filt} removes the underscore by default is target dependent.
1816 Prints demangled names using Java syntax. The default is to use C++
1820 @itemx --no-strip-underscores
1821 Do not remove the initial underscore.
1823 @item -s @var{format}
1824 @itemx --format=@var{format}
1825 @sc{gnu} @code{nm} can decode three different methods of mangling, used by
1826 different C++ compilers. The argument to this option selects which
1831 the one used by the @sc{gnu} compiler (the default method)
1833 the one used by the Lucid compiler
1835 the one specified by the C++ Annotated Reference Manual
1837 the one used by the HP compiler
1839 the one used by the EDG compiler
1843 Print a summary of the options to @code{c++filt} and exit.
1846 Print the version number of @code{c++filt} and exit.
1850 @emph{Warning:} @code{c++filt} is a new utility, and the details of its
1851 user interface are subject to change in future releases. In particular,
1852 a command-line option may be required in the the future to decode a name
1853 passed as an argument on the command line; in other words,
1856 c++filt @var{symbol}
1860 may in a future release become
1863 c++filt @var{option} @var{symbol}
1871 @cindex address to file name and line number
1874 addr2line [ -b @var{bfdname} | --target=@var{bfdname} ]
1876 [ -e @var{filename} | --exe=@var{filename} ]
1877 [ -f | --functions ] [ -s | --basename ]
1878 [ -H | --help ] [ -V | --version ]
1882 @code{addr2line} translates program addresses into file names and line
1883 numbers. Given an address and an executable, it uses the debugging
1884 information in the executable to figure out which file name and line
1885 number are associated with a given address.
1887 The executable to use is specified with the @code{-e} option. The
1888 default is the file @file{a.out}.
1890 @code{addr2line} has two modes of operation.
1892 In the first, hexadecimal addresses are specified on the command line,
1893 and @code{addr2line} displays the file name and line number for each
1896 In the second, @code{addr2line} reads hexadecimal addresses from
1897 standard input, and prints the file name and line number for each
1898 address on standard output. In this mode, @code{addr2line} may be used
1899 in a pipe to convert dynamically chosen addresses.
1901 The format of the output is @samp{FILENAME:LINENO}. The file name and
1902 line number for each address is printed on a separate line. If the
1903 @code{-f} option is used, then each @samp{FILENAME:LINENO} line is
1904 preceded by a @samp{FUNCTIONNAME} line which is the name of the function
1905 containing the address.
1907 If the file name or function name can not be determined,
1908 @code{addr2line} will print two question marks in their place. If the
1909 line number can not be determined, @code{addr2line} will print 0.
1911 The long and short forms of options, shown here as alternatives, are
1915 @item -b @var{bfdname}
1916 @itemx --target=@var{bfdname}
1917 @cindex object code format
1918 Specify that the object-code format for the object files is
1923 @cindex demangling in objdump
1924 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1925 Besides removing any initial underscore prepended by the system, this
1926 makes C++ function names readable. @xref{c++filt}, for more information
1929 @item -e @var{filename}
1930 @itemx --exe=@var{filename}
1931 Specify the name of the executable for which addresses should be
1932 translated. The default file is @file{a.out}.
1936 Display function names as well as file and line number information.
1940 Display only the base of each file name.
1946 @code{nlmconv} converts a relocatable object file into a NetWare
1950 @code{nlmconv} currently works with @samp{i386} object
1951 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
1952 object files in @sc{elf}, or @code{a.out} format@footnote{
1953 @code{nlmconv} should work with any @samp{i386} or @sc{sparc} object
1954 format in the Binary File Descriptor library. It has only been tested
1955 with the above formats.}.
1959 @emph{Warning:} @code{nlmconv} is not always built as part of the binary
1960 utilities, since it is only useful for NLM targets.
1964 nlmconv [ -I @var{bfdname} | --input-target=@var{bfdname} ]
1965 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
1966 [ -T @var{headerfile} | --header-file=@var{headerfile} ]
1967 [ -d | --debug] [ -l @var{linker} | --linker=@var{linker} ]
1968 [ -h | --help ] [ -V | --version ]
1969 @var{infile} @var{outfile}
1972 @code{nlmconv} converts the relocatable @samp{i386} object file
1973 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
1974 reading @var{headerfile} for NLM header information. For instructions
1975 on writing the NLM command file language used in header files, see the
1976 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
1977 Development and Tools Overview}, which is part of the NLM Software
1978 Developer's Kit (``NLM SDK''), available from Novell, Inc.
1979 @code{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
1980 @var{infile}; see @ref{BFD,,BFD,ld.info,Using LD}, for
1983 @code{nlmconv} can perform a link step. In other words, you can list
1984 more than one object file for input if you list them in the definitions
1985 file (rather than simply specifying one input file on the command line).
1986 In this case, @code{nlmconv} calls the linker for you.
1989 @item -I @var{bfdname}
1990 @itemx --input-target=@var{bfdname}
1991 Object format of the input file. @code{nlmconv} can usually determine
1992 the format of a given file (so no default is necessary).
1993 @xref{Target Selection}, for more information.
1995 @item -O @var{bfdname}
1996 @itemx --output-target=@var{bfdname}
1997 Object format of the output file. @code{nlmconv} infers the output
1998 format based on the input format, e.g. for a @samp{i386} input file the
1999 output format is @samp{nlm32-i386}.
2000 @xref{Target Selection}, for more information.
2002 @item -T @var{headerfile}
2003 @itemx --header-file=@var{headerfile}
2004 Reads @var{headerfile} for NLM header information. For instructions on
2005 writing the NLM command file language used in header files, see@ see the
2006 @samp{linkers} section, of the @cite{NLM Development and Tools
2007 Overview}, which is part of the NLM Software Developer's Kit, available
2012 Displays (on standard error) the linker command line used by @code{nlmconv}.
2014 @item -l @var{linker}
2015 @itemx --linker=@var{linker}
2016 Use @var{linker} for any linking. @var{linker} can be an absolute or a
2021 Prints a usage summary.
2025 Prints the version number for @code{nlmconv}.
2031 @code{windres} may be used to manipulate Windows resources.
2034 @emph{Warning:} @code{windres} is not always built as part of the binary
2035 utilities, since it is only useful for Windows targets.
2039 windres [options] [input-file] [output-file]
2042 @code{windres} reads resources from an input file and copies them into
2043 an output file. Either file may be in one of three formats:
2047 A text format read by the Resource Compiler.
2050 A binary format generated by the Resource Compiler.
2053 A COFF object or executable.
2056 The exact description of these different formats is available in
2057 documentation from Microsoft.
2059 When @code{windres} converts from the @code{rc} format to the @code{res}
2060 format, it is acting like the Windows Resource Compiler. When
2061 @code{windres} converts from the @code{res} format to the @code{coff}
2062 format, it is acting like the Windows @code{CVTRES} program.
2064 When @code{windres} generates an @code{rc} file, the output is similar
2065 but not identical to the format expected for the input. When an input
2066 @code{rc} file refers to an external filename, an output @code{rc} file
2067 will instead include the file contents.
2069 If the input or output format is not specified, @code{windres} will
2070 guess based on the file name, or, for the input file, the file contents.
2071 A file with an extension of @file{.rc} will be treated as an @code{rc}
2072 file, a file with an extension of @file{.res} will be treated as a
2073 @code{res} file, and a file with an extension of @file{.o} or
2074 @file{.exe} will be treated as a @code{coff} file.
2076 If no output file is specified, @code{windres} will print the resources
2077 in @code{rc} format to standard output.
2079 The normal use is for you to write an @code{rc} file, use @code{windres}
2080 to convert it to a COFF object file, and then link the COFF file into
2081 your application. This will make the resources described in the
2082 @code{rc} file available to Windows.
2085 @item -i @var{filename}
2086 @itemx --input @var{filename}
2087 The name of the input file. If this option is not used, then
2088 @code{windres} will use the first non-option argument as the input file
2089 name. If there are no non-option arguments, then @code{windres} will
2090 read from standard input. @code{windres} can not read a COFF file from
2093 @item -o @var{filename}
2094 @itemx --output @var{filename}
2095 The name of the output file. If this option is not used, then
2096 @code{windres} will use the first non-option argument, after any used
2097 for the input file name, as the output file name. If there is no
2098 non-option argument, then @code{windres} will write to standard output.
2099 @code{windres} can not write a COFF file to standard output.
2101 @item -I @var{format}
2102 @itemx --input-format @var{format}
2103 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
2104 @samp{coff}. If no input format is specified, @code{windres} will
2105 guess, as described above.
2107 @item -O @var{format}
2108 @itemx --output-format @var{format}
2109 The output format to generate. @var{format} may be @samp{res},
2110 @samp{rc}, or @samp{coff}. If no output format is specified,
2111 @code{windres} will guess, as described above.
2113 @item -F @var{target}
2114 @itemx --target @var{target}
2115 Specify the BFD format to use for a COFF file as input or output. This
2116 is a BFD target name; you can use the @code{--help} option to see a list
2117 of supported targets. Normally @code{windres} will use the default
2118 format, which is the first one listed by the @code{--help} option.
2119 @ref{Target Selection}.
2121 @item --preprocessor @var{program}
2122 When @code{windres} reads an @code{rc} file, it runs it through the C
2123 preprocessor first. This option may be used to specify the preprocessor
2124 to use, including any leading arguments. The default preprocessor
2125 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
2127 @item --include-dir @var{directory}
2128 Specify an include directory to use when reading an @code{rc} file.
2129 @code{windres} will pass this to the preprocessor as an @code{-I}
2130 option. @code{windres} will also search this directory when looking for
2131 files named in the @code{rc} file.
2133 @item -D @var{target}
2134 @itemx --define @var{sym}[=@var{val}]
2135 Specify a @code{-D} option to pass to the preprocessor when reading an
2139 Enable verbose mode. This tells you what the preprocessor is if you
2142 @item --language @var{val}
2143 Specify the default language to use when reading an @code{rc} file.
2144 @var{val} should be a hexadecimal language code. The low eight bits are
2145 the language, and the high eight bits are the sublanguage.
2147 @item --use-temp-file
2148 Use a temporary file to instead of using popen to read the output of
2149 the preprocessor. Use this option if the popen implementation is buggy
2150 on the host (eg., certain non-English language versions of Windows 95 and
2151 Windows 98 are known to have buggy popen where the output will instead
2154 @item --no-use-temp-file
2155 Use popen, not a temporary file, to read the output of the preprocessor.
2156 This is the default behaviour.
2159 Prints a usage summary.
2162 Prints the version number for @code{windres}.
2165 If @code{windres} is compiled with @code{YYDEBUG} defined as @code{1},
2166 this will turn on parser debugging.
2171 @chapter Create files needed to build and use DLLs
2175 @code{dlltool} may be used to create the files needed to build and use
2176 dynamic link libraries (DLLs).
2179 @emph{Warning:} @code{dlltool} is not always built as part of the binary
2180 utilities, since it is only useful for those targets which support DLLs.
2184 dlltool [-d|--input-def @var{def-file-name}]
2185 [-b|--base-file @var{base-file-name}]
2186 [-e|--output-exp @var{exports-file-name}]
2187 [-z|--output-def @var{def-file-name}]
2188 [-l|--output-lib @var{library-file-name}]
2189 [--export-all-symbols] [--no-export-all-symbols]
2190 [--exclude-symbols @var{list}]
2191 [--no-default-excludes]
2192 [-S|--as @var{path-to-assembler}] [-f|--as-flags @var{options}]
2193 [-D|--dllname @var{name}] [-m|--machine @var{machine}]
2194 [-a|--add-indirect] [-U|--add-underscore] [-k|--kill-at]
2195 [-A|--add-stdcall-alias]
2196 [-x|--no-idata4] [-c|--no-idata5] [-i|--interwork]
2197 [-n|--nodelete] [-v|--verbose] [-h|--help] [-V|--version]
2198 [object-file @dots{}]
2201 @code{dlltool} reads its inputs, which can come from the @samp{-d} and
2202 @samp{-b} options as well as object files specified on the command
2203 line. It then processes these inputs and if the @samp{-e} option has
2204 been specified it creates a exports file. If the @samp{-l} option
2205 has been specified it creates a library file and if the @samp{-z} option
2206 has been specified it creates a def file. Any or all of the -e, -l
2207 and -z options can be present in one invocation of dlltool.
2209 When creating a DLL, along with the source for the DLL, it is necessary
2210 to have three other files. @code{dlltool} can help with the creation of
2213 The first file is a @samp{.def} file which specifies which functions are
2214 exported from the DLL, which functions the DLL imports, and so on. This
2215 is a text file and can be created by hand, or @code{dlltool} can be used
2216 to create it using the @samp{-z} option. In this case @code{dlltool}
2217 will scan the object files specified on its command line looking for
2218 those functions which have been specially marked as being exported and
2219 put entries for them in the .def file it creates.
2221 In order to mark a function as being exported from a DLL, it needs to
2222 have an @samp{-export:<name_of_function>} entry in the @samp{.drectve}
2223 section of the object file. This can be done in C by using the
2227 asm (".section .drectve");
2228 asm (".ascii \"-export:my_func\"");
2230 int my_func (void) @{ @dots{} @}
2233 The second file needed for DLL creation is an exports file. This file
2234 is linked with the object files that make up the body of the DLL and it
2235 handles the interface between the DLL and the outside world. This is a
2236 binary file and it can be created by giving the @samp{-e} option to
2237 @code{dlltool} when it is creating or reading in a .def file.
2239 The third file needed for DLL creation is the library file that programs
2240 will link with in order to access the functions in the DLL. This file
2241 can be created by giving the @samp{-l} option to dlltool when it
2242 is creating or reading in a .def file.
2244 @code{dlltool} builds the library file by hand, but it builds the
2245 exports file by creating temporary files containing assembler statements
2246 and then assembling these. The @samp{-S} command line option can be
2247 used to specify the path to the assembler that dlltool will use,
2248 and the @samp{-f} option can be used to pass specific flags to that
2249 assembler. The @samp{-n} can be used to prevent dlltool from deleting
2250 these temporary assembler files when it is done, and if @samp{-n} is
2251 specified twice then this will prevent dlltool from deleting the
2252 temporary object files it used to build the library.
2254 Here is an example of creating a DLL from a source file @samp{dll.c} and
2255 also creating a program (from an object file called @samp{program.o})
2260 dlltool -e exports.o -l dll.lib dll.o
2261 gcc dll.o exports.o -o dll.dll
2262 gcc program.o dll.lib -o program
2265 The command line options have the following meanings:
2269 @item -d @var{filename}
2270 @itemx --input-def @var{filename}
2271 @cindex input .def file
2272 Specifies the name of a .def file to be read in and processed.
2274 @item -b @var{filename}
2275 @itemx --base-file @var{filename}
2277 Specifies the name of a base file to be read in and processed. The
2278 contents of this file will be added to the relocation section in the
2279 exports file generated by dlltool.
2281 @item -e @var{filename}
2282 @itemx --output-exp @var{filename}
2283 Specifies the name of the export file to be created by dlltool.
2285 @item -z @var{filename}
2286 @itemx --output-def @var{filename}
2287 Specifies the name of the .def file to be created by dlltool.
2289 @item -l @var{filename}
2290 @itemx --output-lib @var{filename}
2291 Specifies the name of the library file to be created by dlltool.
2293 @item --export-all-symbols
2294 Treat all global and weak defined symbols found in the input object
2295 files as symbols to be exported. There is a small list of symbols which
2296 are not exported by default; see the @code{--no-default-excludes}
2297 option. You may add to the list of symbols to not export by using the
2298 @code{--exclude-symbols} option.
2300 @item --no-export-all-symbols
2301 Only export symbols explicitly listed in an input .def file or in
2302 @samp{.drectve} sections in the input object files. This is the default
2303 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
2304 attributes in the source code.
2306 @item --exclude-symbols @var{list}
2307 Do not export the symbols in @var{list}. This is a list of symbol names
2308 separated by comma or colon characters. The symbol names should not
2309 contain a leading underscore. This is only meaningful when
2310 @code{--export-all-symbols} is used.
2312 @item --no-default-excludes
2313 When @code{--export-all-symbols} is used, it will by default avoid
2314 exporting certain special symbols. The current list of symbols to avoid
2315 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
2316 @samp{impure_ptr}. You may use the @code{--no-default-excludes} option
2317 to go ahead and export these special symbols. This is only meaningful
2318 when @code{--export-all-symbols} is used.
2321 @itemx --as @var{path}
2322 Specifies the path, including the filename, of the assembler to be used
2323 to create the exports file.
2325 @item -f @var{switches}
2326 @itemx --as-flags @var{switches}
2327 Specifies any specific command line switches to be passed to the
2328 assembler when building the exports file. This option will work even if
2329 the @samp{-S} option is not used. This option only takes one argument,
2330 and if it occurs more than once on the command line, then later
2331 occurrences will override earlier occurrences. So if it is necessary to
2332 pass multiple switches to the assembler they should be enclosed in
2336 @itemx --dll-name @var{name}
2337 Specifies the name to be stored in the .def file as the name of the DLL
2338 when the @samp{-e} option is used. If this option is not present, then
2339 the filename given to the @samp{-e} option will be used as the name of
2342 @item -m @var{machine}
2343 @itemx -machine @var{machine}
2344 Specifies the type of machine for which the library file should be
2345 built. @code{dlltool} has a built in default type, depending upon how
2346 it was created, but this option can be used to override that. This is
2347 normally only useful when creating DLLs for an ARM processor, when the
2348 contents of the DLL are actually encode using THUMB instructions.
2351 @itemx --add-indirect
2352 Specifies that when @code{dlltool} is creating the exports file it
2353 should add a section which allows the exported functions to be
2354 referenced without using the import library. Whatever the hell that
2358 @itemx --add-underscore
2359 Specifies that when @code{dlltool} is creating the exports file it
2360 should prepend an underscore to the names of the exported functions.
2364 Specifies that when @code{dlltool} is creating the exports file it
2365 should not append the string @samp{@@ <number>}. These numbers are
2366 called ordinal numbers and they represent another way of accessing the
2367 function in a DLL, other than by name.
2370 @itemx --add-stdcall-alias
2371 Specifies that when @code{dlltool} is creating the exports file it
2372 should add aliases for stdcall symbols without @samp{@@ <number>}
2373 in addition to the symbols with @samp{@@ <number>}.
2377 Specifies that when @code{dlltool} is creating the exports and library
2378 files it should omit the .idata4 section. This is for compatibility
2379 with certain operating systems.
2383 Specifies that when @code{dlltool} is creating the exports and library
2384 files it should omit the .idata5 section. This is for compatibility
2385 with certain operating systems.
2389 Specifies that @code{dlltool} should mark the objects in the library
2390 file and exports file that it produces as supporting interworking
2391 between ARM and THUMB code.
2395 Makes @code{dlltool} preserve the temporary assembler files it used to
2396 create the exports file. If this option is repeated then dlltool will
2397 also preserve the temporary object files it uses to create the library
2402 Make dlltool describe what it is doing.
2406 Displays a list of command line options and then exits.
2410 Displays dlltool's version number and then exits.
2417 @cindex ELF file information
2421 readelf [ -a | --all ]
2422 [ -h | --file-header]
2423 [ -l | --program-headers | --segments]
2424 [ -S | --section-headers | --sections]
2426 [ -s | --syms | --symbols]
2430 [ -V | --version-info]
2431 [ -D | --use-dynamic]
2432 [ -x <number> | --hex-dump=<number>]
2433 [ -w[liapr] | --debug-dump[=info,=line,=abbrev,=pubnames,=ranges]]
2437 @var{elffile}@dots{}
2440 @code{readelf} displays information about one or more ELF format object
2441 files. The options control what particular information to display.
2443 @var{elffile}@dots{} are the object files to be examined. At the
2444 moment, @code{readelf} does not support examining archives, nor does it
2445 support examing 64 bit ELF files.
2447 The long and short forms of options, shown here as alternatives, are
2448 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
2454 Equivalent to specifiying @samp{--file-header},
2455 @samp{--program-headers}, @samp{--sections}, @samp{--symbols},
2456 @samp{--relocs}, @samp{--dynamic}, @samp{--notes} and
2457 @samp{--version-info}.
2460 @itemx --file-header
2461 @cindex ELF file header information
2462 Displays the information contained in the ELF header at the start of the
2466 @itemx --program-headers
2468 @cindex ELF program header information
2469 @cindex ELF segment information
2470 Displays the information contained in the file's segment headers, if it
2475 @itemx --section-headers
2476 @cindex ELF section information
2477 Displays the information contained in the file's section headers, if it
2483 @cindex ELF symbol table information
2484 Displays the entries in symbol table section of the file, if it has one.
2488 Display all the headers in the file. Equivalent to @samp{-h -l -S}.
2492 @cindex ELF core notes
2493 Displays the contents of the NOTE segment, if it exists.
2497 @cindex ELF reloc information
2498 Displays the contents of the file's relocation section, if it ha one.
2502 @cindex ELF dynamic section information
2503 Displays the contents of the file's dynamic section, if it has one.
2506 @itemx --version-info
2507 @cindex ELF version sections informations
2508 Displays the contents of the version sections in the file, it they
2512 @itemx --use-dynamic
2513 When displaying symbols, this option makes @code{readelf} use the
2514 symblol table in the file's dynamic section, rather than the one in the
2518 @itemx --hex-dump=<number>
2519 Displays the contents of the indicated section as a hexadecimal dump.
2522 @itemx --debug-dump[=line,=info,=abbrev,=pubnames,=ranges]
2523 Displays the contents of the debug sections in the file, if any are
2524 present. If one of the optional letters or words follows the switch
2525 then only data found in those specific sections will be dumped.
2528 Display a histogram of bucket list lengths when displaying the contents
2529 of the symbol tables.
2533 Display the version number of readelf.
2537 Display the command line options understood by @code{readelf}.
2542 @node Selecting The Target System
2543 @chapter Selecting the target system
2545 You can specify three aspects of the target system to the @sc{gnu}
2546 binary file utilities, each in several ways:
2556 the linker emulation (which applies to the linker only)
2559 In the following summaries, the lists of ways to specify values are in
2560 order of decreasing precedence. The ways listed first override those
2563 The commands to list valid values only list the values for which the
2564 programs you are running were configured. If they were configured with
2565 @samp{--enable-targets=all}, the commands list most of the available
2566 values, but a few are left out; not all targets can be configured in at
2567 once because some of them can only be configured @dfn{native} (on hosts
2568 with the same type as the target system).
2571 * Target Selection::
2572 * Architecture Selection::
2573 * Linker Emulation Selection::
2576 @node Target Selection
2577 @section Target Selection
2579 A @dfn{target} is an object file format. A given target may be
2580 supported for multiple architectures (@pxref{Architecture Selection}).
2581 A target selection may also have variations for different operating
2582 systems or architectures.
2584 The command to list valid target values is @samp{objdump -i}
2585 (the first column of output contains the relevant information).
2587 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
2588 @samp{a.out-sunos-big}.
2590 You can also specify a target using a configuration triplet. This is
2591 the same sort of name that is passed to @file{configure} to specify a
2592 target. When you use a configuration triplet as an argument, it must be
2593 fully canonicalized. You can see the canonical version of a triplet by
2594 running the shell script @file{config.sub} which is included with the
2597 Some sample configuration triplets are: @samp{m68k-hp-bsd},
2598 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
2600 @subheading @code{objdump} Target
2606 command line option: @samp{-b} or @samp{--target}
2609 environment variable @code{GNUTARGET}
2612 deduced from the input file
2615 @subheading @code{objcopy} and @code{strip} Input Target
2621 command line options: @samp{-I} or @samp{--input-target}, or @samp{-F} or @samp{--target}
2624 environment variable @code{GNUTARGET}
2627 deduced from the input file
2630 @subheading @code{objcopy} and @code{strip} Output Target
2636 command line options: @samp{-O} or @samp{--output-target}, or @samp{-F} or @samp{--target}
2639 the input target (see ``@code{objcopy} and @code{strip} Input Target'' above)
2642 environment variable @code{GNUTARGET}
2645 deduced from the input file
2648 @subheading @code{nm}, @code{size}, and @code{strings} Target
2654 command line option: @samp{--target}
2657 environment variable @code{GNUTARGET}
2660 deduced from the input file
2663 @subheading Linker Input Target
2669 command line option: @samp{-b} or @samp{--format}
2670 (@pxref{Options,,Options,ld.info,Using LD})
2673 script command @code{TARGET}
2674 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
2677 environment variable @code{GNUTARGET}
2678 (@pxref{Environment,,Environment,ld.info,Using LD})
2681 the default target of the selected linker emulation
2682 (@pxref{Linker Emulation Selection})
2685 @subheading Linker Output Target
2691 command line option: @samp{-oformat}
2692 (@pxref{Options,,Options,ld.info,Using LD})
2695 script command @code{OUTPUT_FORMAT}
2696 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
2699 the linker input target (see ``Linker Input Target'' above)
2702 @node Architecture Selection
2703 @section Architecture selection
2705 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
2706 to run. Its name may contain a colon, separating the name of the
2707 processor family from the name of the particular @sc{cpu}.
2709 The command to list valid architecture values is @samp{objdump -i} (the
2710 second column contains the relevant information).
2712 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
2714 @subheading @code{objdump} Architecture
2720 command line option: @samp{-m} or @samp{--architecture}
2723 deduced from the input file
2726 @subheading @code{objcopy}, @code{nm}, @code{size}, @code{strings} Architecture
2732 deduced from the input file
2735 @subheading Linker Input Architecture
2741 deduced from the input file
2744 @subheading Linker Output Architecture
2750 script command @code{OUTPUT_ARCH}
2751 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
2754 the default architecture from the linker output target
2755 (@pxref{Target Selection})
2758 @node Linker Emulation Selection
2759 @section Linker emulation selection
2761 A linker @dfn{emulation} is a ``personality'' of the linker, which gives
2762 the linker default values for the other aspects of the target system.
2763 In particular, it consists of
2773 several ``hook'' functions that are run at certain stages of the linking
2774 process to do special things that some targets require
2777 The command to list valid linker emulation values is @samp{ld -V}.
2779 Sample values: @samp{hp300bsd}, @samp{mipslit}, @samp{sun4}.
2785 command line option: @samp{-m}
2786 (@pxref{Options,,Options,ld.info,Using LD})
2789 environment variable @code{LDEMULATION}
2792 compiled-in @code{DEFAULT_EMULATION} from @file{Makefile},
2793 which comes from @code{EMUL} in @file{config/@var{target}.mt}
2796 @node Reporting Bugs
2797 @chapter Reporting Bugs
2799 @cindex reporting bugs
2801 Your bug reports play an essential role in making the binary utilities
2804 Reporting a bug may help you by bringing a solution to your problem, or
2805 it may not. But in any case the principal function of a bug report is
2806 to help the entire community by making the next version of the binary
2807 utilities work better. Bug reports are your contribution to their
2810 In order for a bug report to serve its purpose, you must include the
2811 information that enables us to fix the bug.
2814 * Bug Criteria:: Have you found a bug?
2815 * Bug Reporting:: How to report bugs
2819 @section Have you found a bug?
2820 @cindex bug criteria
2822 If you are not sure whether you have found a bug, here are some guidelines:
2825 @cindex fatal signal
2828 If a binary utility gets a fatal signal, for any input whatever, that is
2829 a bug. Reliable utilities never crash.
2831 @cindex error on valid input
2833 If a binary utility produces an error message for valid input, that is a
2837 If you are an experienced user of binary utilities, your suggestions for
2838 improvement are welcome in any case.
2842 @section How to report bugs
2844 @cindex bugs, reporting
2846 A number of companies and individuals offer support for @sc{gnu}
2847 products. If you obtained the binary utilities from a support
2848 organization, we recommend you contact that organization first.
2850 You can find contact information for many support companies and
2851 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
2854 In any event, we also recommend that you send bug reports for the binary
2855 utilities to @samp{bug-gnu-utils@@gnu.org}.
2857 The fundamental principle of reporting bugs usefully is this:
2858 @strong{report all the facts}. If you are not sure whether to state a
2859 fact or leave it out, state it!
2861 Often people omit facts because they think they know what causes the
2862 problem and assume that some details do not matter. Thus, you might
2863 assume that the name of a file you use in an example does not matter.
2864 Well, probably it does not, but one cannot be sure. Perhaps the bug is
2865 a stray memory reference which happens to fetch from the location where
2866 that pathname is stored in memory; perhaps, if the pathname were
2867 different, the contents of that location would fool the utility into
2868 doing the right thing despite the bug. Play it safe and give a
2869 specific, complete example. That is the easiest thing for you to do,
2870 and the most helpful.
2872 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
2873 it is new to us. Therefore, always write your bug reports on the assumption
2874 that the bug has not been reported previously.
2876 Sometimes people give a few sketchy facts and ask, ``Does this ring a
2877 bell?'' Those bug reports are useless, and we urge everyone to
2878 @emph{refuse to respond to them} except to chide the sender to report
2881 To enable us to fix the bug, you should include all these things:
2885 The version of the utility. Each utility announces it if you start it
2886 with the @samp{--version} argument.
2888 Without this, we will not know whether there is any point in looking for
2889 the bug in the current version of the binary utilities.
2892 Any patches you may have applied to the source, including any patches
2893 made to the @code{BFD} library.
2896 The type of machine you are using, and the operating system name and
2900 What compiler (and its version) was used to compile the utilities---e.g.
2904 The command arguments you gave the utility to observe the bug. To
2905 guarantee you will not omit something important, list them all. A copy
2906 of the Makefile (or the output from make) is sufficient.
2908 If we were to try to guess the arguments, we would probably guess wrong
2909 and then we might not encounter the bug.
2912 A complete input file, or set of input files, that will reproduce the
2913 bug. If the utility is reading an object file or files, then it is
2914 generally most helpful to send the actual object files, uuencoded if
2915 necessary to get them through the mail system. Note that
2916 @samp{bug-gnu-utils@@gnu.org} is a mailing list, so you should avoid
2917 sending very large files to it. Making the files available for
2918 anonymous FTP is OK.
2920 If the source files were produced exclusively using @sc{gnu} programs
2921 (e.g., @code{gcc}, @code{gas}, and/or the @sc{gnu} @code{ld}), then it
2922 may be OK to send the source files rather than the object files. In
2923 this case, be sure to say exactly what version of @code{gcc}, or
2924 whatever, was used to produce the object files. Also say how
2925 @code{gcc}, or whatever, was configured.
2928 A description of what behavior you observe that you believe is
2929 incorrect. For example, ``It gets a fatal signal.''
2931 Of course, if the bug is that the utility gets a fatal signal, then we
2932 will certainly notice it. But if the bug is incorrect output, we might
2933 not notice unless it is glaringly wrong. You might as well not give us
2934 a chance to make a mistake.
2936 Even if the problem you experience is a fatal signal, you should still
2937 say so explicitly. Suppose something strange is going on, such as your
2938 copy of the utility is out of synch, or you have encountered a bug in
2939 the C library on your system. (This has happened!) Your copy might
2940 crash and ours would not. If you told us to expect a crash, then when
2941 ours fails to crash, we would know that the bug was not happening for
2942 us. If you had not told us to expect a crash, then we would not be able
2943 to draw any conclusion from our observations.
2946 If you wish to suggest changes to the source, send us context diffs, as
2947 generated by @code{diff} with the @samp{-u}, @samp{-c}, or @samp{-p}
2948 option. Always send diffs from the old file to the new file. If you
2949 wish to discuss something in the @code{ld} source, refer to it by
2950 context, not by line number.
2952 The line numbers in our development sources will not match those in your
2953 sources. Your line numbers would convey no useful information to us.
2956 Here are some things that are not necessary:
2960 A description of the envelope of the bug.
2962 Often people who encounter a bug spend a lot of time investigating
2963 which changes to the input file will make the bug go away and which
2964 changes will not affect it.
2966 This is often time consuming and not very useful, because the way we
2967 will find the bug is by running a single example under the debugger
2968 with breakpoints, not by pure deduction from a series of examples.
2969 We recommend that you save your time for something else.
2971 Of course, if you can find a simpler example to report @emph{instead}
2972 of the original one, that is a convenience for us. Errors in the
2973 output will be easier to spot, running under the debugger will take
2974 less time, and so on.
2976 However, simplification is not vital; if you do not want to do this,
2977 report the bug anyway and send us the entire test case you used.
2980 A patch for the bug.
2982 A patch for the bug does help us if it is a good one. But do not omit
2983 the necessary information, such as the test case, on the assumption that
2984 a patch is all we need. We might see problems with your patch and decide
2985 to fix the problem another way, or we might not understand it at all.
2987 Sometimes with programs as complicated as the binary utilities it is
2988 very hard to construct an example that will make the program follow a
2989 certain path through the code. If you do not send us the example, we
2990 will not be able to construct one, so we will not be able to verify that
2993 And if we cannot understand what bug you are trying to fix, or why your
2994 patch should be an improvement, we will not install it. A test case will
2995 help us to understand.
2998 A guess about what the bug is or what it depends on.
3000 Such guesses are usually wrong. Even we cannot guess right about such
3001 things without first using the debugger to find the facts.