1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @c Copyright 2001, 2002, 2003 Free Software Foundation, Inc.
10 * Binutils: (binutils). The GNU binary utilities.
11 * ar: (binutils)ar. Create, modify, and extract from archives
12 * nm: (binutils)nm. List symbols from object files
13 * objcopy: (binutils)objcopy. Copy and translate object files
14 * objdump: (binutils)objdump. Display information from object files
15 * ranlib: (binutils)ranlib. Generate index to archive contents
16 * readelf: (binutils)readelf. Display the contents of ELF format files.
17 * size: (binutils)size. List section sizes and total size
18 * strings: (binutils)strings. List printable strings from files
19 * strip: (binutils)strip. Discard symbols
20 * c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols
21 * cxxfilt: (binutils)c++filt. MS-DOS name for c++filt
22 * addr2line: (binutils)addr2line. Convert addresses to file and line
23 * nlmconv: (binutils)nlmconv. Converts object code into an NLM
24 * windres: (binutils)windres. Manipulate Windows resources
25 * dlltool: (binutils)dlltool. Create files needed to build and use DLLs
31 @c man begin COPYRIGHT
32 Copyright @copyright{} 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000,
33 2001, 2002, 2003 Free Software Foundation, Inc.
35 Permission is granted to copy, distribute and/or modify this document
36 under the terms of the GNU Free Documentation License, Version 1.1
37 or any later version published by the Free Software Foundation;
38 with no Invariant Sections, with no Front-Cover Texts, and with no
39 Back-Cover Texts. A copy of the license is included in the
40 section entitled ``GNU Free Documentation License''.
44 Permission is granted to process this file through TeX and print the
45 results, provided the printed document carries a copying permission
46 notice identical to this one except for the removal of this paragraph
47 (this paragraph not being relevant to the printed manual).
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, 2001,
58 @c 2002, 2003 Free Software Foundation, Inc.
60 @c This text may be freely distributed under the terms of the GNU
61 @c Free Documentation License.
64 @setchapternewpage odd
65 @settitle @sc{gnu} Binary Utilities
68 @title The @sc{gnu} Binary Utilities
69 @subtitle Version @value{VERSION}
72 @author Roland H. Pesch
73 @author Jeffrey M. Osier
74 @author Cygnus Support
78 {\parskip=0pt \hfill Cygnus Support\par \hfill
79 \TeX{}info \texinfoversion\par }
82 @vskip 0pt plus 1filll
83 Copyright @copyright{} 1991, 92, 93, 94, 95, 96, 97, 1998, 2000, 2001,
84 2002, 2003 Free Software Foundation, Inc.
86 Permission is granted to copy, distribute and/or modify this document
87 under the terms of the GNU Free Documentation License, Version 1.1
88 or any later version published by the Free Software Foundation;
89 with no Invariant Sections, with no Front-Cover Texts, and with no
90 Back-Cover Texts. A copy of the license is included in the
91 section entitled ``GNU Free Documentation License''.
99 This brief manual contains documentation for the @sc{gnu} binary
100 utilities (collectively version @value{VERSION}):
105 Create, modify, and extract from archives
108 List symbols from object files
111 Copy and translate object files
114 Display information from object files
117 Generate index to archive contents
120 Display the contents of ELF format files.
123 List file section sizes and total size
126 List printable strings from files
132 Demangle encoded C++ symbols (on MS-DOS, this program is named
136 Convert addresses into file names and line numbers
139 Convert object code into a Netware Loadable Module
142 Manipulate Windows resources
145 Create the files needed to build and use Dynamic Link Libraries
149 This document is distributed under the terms of the GNU Free
150 Documentation License. A copy of the license is included in the
151 section entitled "GNU Free Documentation License".
154 * ar:: Create, modify, and extract from archives
155 * nm:: List symbols from object files
156 * objcopy:: Copy and translate object files
157 * objdump:: Display information from object files
158 * ranlib:: Generate index to archive contents
159 * readelf:: Display the contents of ELF format files.
160 * size:: List section sizes and total size
161 * strings:: List printable strings from files
162 * strip:: Discard symbols
163 * c++filt:: Filter to demangle encoded C++ symbols
164 * cxxfilt: c++filt. MS-DOS name for c++filt
165 * addr2line:: Convert addresses to file and line
166 * nlmconv:: Converts object code into an NLM
167 * windres:: Manipulate Windows resources
168 * dlltool:: Create files needed to build and use DLLs
169 * Selecting The Target System:: How these utilities determine the target.
170 * Reporting Bugs:: Reporting Bugs
171 * GNU Free Documentation License:: GNU Free Documentation License
180 @cindex collections of files
182 @c man title ar create, modify, and extract from archives
185 ar [-]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
186 ar -M [ <mri-script ]
189 @c man begin DESCRIPTION ar
191 The @sc{gnu} @command{ar} program creates, modifies, and extracts from
192 archives. An @dfn{archive} is a single file holding a collection of
193 other files in a structure that makes it possible to retrieve
194 the original individual files (called @dfn{members} of the archive).
196 The original files' contents, mode (permissions), timestamp, owner, and
197 group are preserved in the archive, and can be restored on
201 @sc{gnu} @command{ar} can maintain archives whose members have names of any
202 length; however, depending on how @command{ar} is configured on your
203 system, a limit on member-name length may be imposed for compatibility
204 with archive formats maintained with other tools. If it exists, the
205 limit is often 15 characters (typical of formats related to a.out) or 16
206 characters (typical of formats related to coff).
209 @command{ar} is considered a binary utility because archives of this sort
210 are most often used as @dfn{libraries} holding commonly needed
214 @command{ar} creates an index to the symbols defined in relocatable
215 object modules in the archive when you specify the modifier @samp{s}.
216 Once created, this index is updated in the archive whenever @command{ar}
217 makes a change to its contents (save for the @samp{q} update operation).
218 An archive with such an index speeds up linking to the library, and
219 allows routines in the library to call each other without regard to
220 their placement in the archive.
222 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
223 table. If an archive lacks the table, another form of @command{ar} called
224 @command{ranlib} can be used to add just the table.
226 @cindex compatibility, @command{ar}
227 @cindex @command{ar} compatibility
228 @sc{gnu} @command{ar} is designed to be compatible with two different
229 facilities. You can control its activity using command-line options,
230 like the different varieties of @command{ar} on Unix systems; or, if you
231 specify the single command-line option @option{-M}, you can control it
232 with a script supplied via standard input, like the MRI ``librarian''
238 * ar cmdline:: Controlling @command{ar} on the command line
239 * ar scripts:: Controlling @command{ar} with a script
244 @section Controlling @command{ar} on the Command Line
247 @c man begin SYNOPSIS ar
248 ar [@option{-X32_64}] [@option{-}]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
252 @cindex Unix compatibility, @command{ar}
253 When you use @command{ar} in the Unix style, @command{ar} insists on at least two
254 arguments to execute: one keyletter specifying the @emph{operation}
255 (optionally accompanied by other keyletters specifying
256 @emph{modifiers}), and the archive name to act on.
258 Most operations can also accept further @var{member} arguments,
259 specifying particular files to operate on.
261 @c man begin OPTIONS ar
263 @sc{gnu} @command{ar} allows you to mix the operation code @var{p} and modifier
264 flags @var{mod} in any order, within the first command-line argument.
266 If you wish, you may begin the first command-line argument with a
269 @cindex operations on archive
270 The @var{p} keyletter specifies what operation to execute; it may be
271 any of the following, but you must specify only one of them:
275 @cindex deleting from archive
276 @emph{Delete} modules from the archive. Specify the names of modules to
277 be deleted as @var{member}@dots{}; the archive is untouched if you
278 specify no files to delete.
280 If you specify the @samp{v} modifier, @command{ar} lists each module
284 @cindex moving in archive
285 Use this operation to @emph{move} members in an archive.
287 The ordering of members in an archive can make a difference in how
288 programs are linked using the library, if a symbol is defined in more
291 If no modifiers are used with @code{m}, any members you name in the
292 @var{member} arguments are moved to the @emph{end} of the archive;
293 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
294 specified place instead.
297 @cindex printing from archive
298 @emph{Print} the specified members of the archive, to the standard
299 output file. If the @samp{v} modifier is specified, show the member
300 name before copying its contents to standard output.
302 If you specify no @var{member} arguments, all the files in the archive are
306 @cindex quick append to archive
307 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
308 @var{archive}, without checking for replacement.
310 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
311 operation; new members are always placed at the end of the archive.
313 The modifier @samp{v} makes @command{ar} list each file as it is appended.
315 Since the point of this operation is speed, the archive's symbol table
316 index is not updated, even if it already existed; you can use @samp{ar s} or
317 @command{ranlib} explicitly to update the symbol table index.
319 However, too many different systems assume quick append rebuilds the
320 index, so @sc{gnu} @command{ar} implements @samp{q} as a synonym for @samp{r}.
323 @cindex replacement in archive
324 Insert the files @var{member}@dots{} into @var{archive} (with
325 @emph{replacement}). This operation differs from @samp{q} in that any
326 previously existing members are deleted if their names match those being
329 If one of the files named in @var{member}@dots{} does not exist, @command{ar}
330 displays an error message, and leaves undisturbed any existing members
331 of the archive matching that name.
333 By default, new members are added at the end of the file; but you may
334 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
335 placement relative to some existing member.
337 The modifier @samp{v} used with this operation elicits a line of
338 output for each file inserted, along with one of the letters @samp{a} or
339 @samp{r} to indicate whether the file was appended (no old member
340 deleted) or replaced.
343 @cindex contents of archive
344 Display a @emph{table} listing the contents of @var{archive}, or those
345 of the files listed in @var{member}@dots{} that are present in the
346 archive. Normally only the member name is shown; if you also want to
347 see the modes (permissions), timestamp, owner, group, and size, you can
348 request that by also specifying the @samp{v} modifier.
350 If you do not specify a @var{member}, all files in the archive
353 @cindex repeated names in archive
354 @cindex name duplication in archive
355 If there is more than one file with the same name (say, @samp{fie}) in
356 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
357 first instance; to see them all, you must ask for a complete
358 listing---in our example, @samp{ar t b.a}.
359 @c WRS only; per Gumby, this is implementation-dependent, and in a more
360 @c recent case in fact works the other way.
363 @cindex extract from archive
364 @emph{Extract} members (named @var{member}) from the archive. You can
365 use the @samp{v} modifier with this operation, to request that
366 @command{ar} list each name as it extracts it.
368 If you do not specify a @var{member}, all files in the archive
373 A number of modifiers (@var{mod}) may immediately follow the @var{p}
374 keyletter, to specify variations on an operation's behavior:
378 @cindex relative placement in archive
379 Add new files @emph{after} an existing member of the
380 archive. If you use the modifier @samp{a}, the name of an existing archive
381 member must be present as the @var{relpos} argument, before the
382 @var{archive} specification.
385 Add new files @emph{before} an existing member of the
386 archive. If you use the modifier @samp{b}, the name of an existing archive
387 member must be present as the @var{relpos} argument, before the
388 @var{archive} specification. (same as @samp{i}).
391 @cindex creating archives
392 @emph{Create} the archive. The specified @var{archive} is always
393 created if it did not exist, when you request an update. But a warning is
394 issued unless you specify in advance that you expect to create it, by
398 Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
399 names of any length. This will cause it to create archives which are
400 not compatible with the native @command{ar} program on some systems. If
401 this is a concern, the @samp{f} modifier may be used to truncate file
402 names when putting them in the archive.
405 Insert new files @emph{before} an existing member of the
406 archive. If you use the modifier @samp{i}, the name of an existing archive
407 member must be present as the @var{relpos} argument, before the
408 @var{archive} specification. (same as @samp{b}).
411 This modifier is accepted but not used.
412 @c whaffor ar l modifier??? presumably compat; with
413 @c what???---doc@@cygnus.com, 25jan91
416 Uses the @var{count} parameter. This is used if there are multiple
417 entries in the archive with the same name. Extract or delete instance
418 @var{count} of the given name from the archive.
421 @cindex dates in archive
422 Preserve the @emph{original} dates of members when extracting them. If
423 you do not specify this modifier, files extracted from the archive
424 are stamped with the time of extraction.
427 Use the full path name when matching names in the archive. @sc{gnu}
428 @command{ar} can not create an archive with a full path name (such archives
429 are not POSIX complaint), but other archive creators can. This option
430 will cause @sc{gnu} @command{ar} to match file names using a complete path
431 name, which can be convenient when extracting a single file from an
432 archive created by another tool.
435 @cindex writing archive index
436 Write an object-file index into the archive, or update an existing one,
437 even if no other change is made to the archive. You may use this modifier
438 flag either with any operation, or alone. Running @samp{ar s} on an
439 archive is equivalent to running @samp{ranlib} on it.
442 @cindex not writing archive index
443 Do not generate an archive symbol table. This can speed up building a
444 large library in several steps. The resulting archive can not be used
445 with the linker. In order to build a symbol table, you must omit the
446 @samp{S} modifier on the last execution of @samp{ar}, or you must run
447 @samp{ranlib} on the archive.
450 @cindex updating an archive
451 Normally, @samp{ar r}@dots{} inserts all files
452 listed into the archive. If you would like to insert @emph{only} those
453 of the files you list that are newer than existing members of the same
454 names, use this modifier. The @samp{u} modifier is allowed only for the
455 operation @samp{r} (replace). In particular, the combination @samp{qu} is
456 not allowed, since checking the timestamps would lose any speed
457 advantage from the operation @samp{q}.
460 This modifier requests the @emph{verbose} version of an operation. Many
461 operations display additional information, such as filenames processed,
462 when the modifier @samp{v} is appended.
465 This modifier shows the version number of @command{ar}.
468 @command{ar} ignores an initial option spelt @samp{-X32_64}, for
469 compatibility with AIX. The behaviour produced by this option is the
470 default for @sc{gnu} @command{ar}. @command{ar} does not support any of the other
471 @samp{-X} options; in particular, it does not support @option{-X32}
472 which is the default for AIX @command{ar}.
477 @c man begin SEEALSO ar
478 nm(1), ranlib(1), and the Info entries for @file{binutils}.
483 @section Controlling @command{ar} with a Script
486 ar -M [ <@var{script} ]
489 @cindex MRI compatibility, @command{ar}
490 @cindex scripts, @command{ar}
491 If you use the single command-line option @samp{-M} with @command{ar}, you
492 can control its operation with a rudimentary command language. This
493 form of @command{ar} operates interactively if standard input is coming
494 directly from a terminal. During interactive use, @command{ar} prompts for
495 input (the prompt is @samp{AR >}), and continues executing even after
496 errors. If you redirect standard input to a script file, no prompts are
497 issued, and @command{ar} abandons execution (with a nonzero exit code)
500 The @command{ar} command language is @emph{not} designed to be equivalent
501 to the command-line options; in fact, it provides somewhat less control
502 over archives. The only purpose of the command language is to ease the
503 transition to @sc{gnu} @command{ar} for developers who already have scripts
504 written for the MRI ``librarian'' program.
506 The syntax for the @command{ar} command language is straightforward:
509 commands are recognized in upper or lower case; for example, @code{LIST}
510 is the same as @code{list}. In the following descriptions, commands are
511 shown in upper case for clarity.
514 a single command may appear on each line; it is the first word on the
518 empty lines are allowed, and have no effect.
521 comments are allowed; text after either of the characters @samp{*}
522 or @samp{;} is ignored.
525 Whenever you use a list of names as part of the argument to an @command{ar}
526 command, you can separate the individual names with either commas or
527 blanks. Commas are shown in the explanations below, for clarity.
530 @samp{+} is used as a line continuation character; if @samp{+} appears
531 at the end of a line, the text on the following line is considered part
532 of the current command.
535 Here are the commands you can use in @command{ar} scripts, or when using
536 @command{ar} interactively. Three of them have special significance:
538 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
539 a temporary file required for most of the other commands.
541 @code{SAVE} commits the changes so far specified by the script. Prior
542 to @code{SAVE}, commands affect only the temporary copy of the current
546 @item ADDLIB @var{archive}
547 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
548 Add all the contents of @var{archive} (or, if specified, each named
549 @var{module} from @var{archive}) to the current archive.
551 Requires prior use of @code{OPEN} or @code{CREATE}.
553 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
554 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
555 @c else like "ar q..."
556 Add each named @var{member} as a module in the current archive.
558 Requires prior use of @code{OPEN} or @code{CREATE}.
561 Discard the contents of the current archive, canceling the effect of
562 any operations since the last @code{SAVE}. May be executed (with no
563 effect) even if no current archive is specified.
565 @item CREATE @var{archive}
566 Creates an archive, and makes it the current archive (required for many
567 other commands). The new archive is created with a temporary name; it
568 is not actually saved as @var{archive} until you use @code{SAVE}.
569 You can overwrite existing archives; similarly, the contents of any
570 existing file named @var{archive} will not be destroyed until @code{SAVE}.
572 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
573 Delete each listed @var{module} from the current archive; equivalent to
574 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
576 Requires prior use of @code{OPEN} or @code{CREATE}.
578 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
579 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
580 List each named @var{module} present in @var{archive}. The separate
581 command @code{VERBOSE} specifies the form of the output: when verbose
582 output is off, output is like that of @samp{ar -t @var{archive}
583 @var{module}@dots{}}. When verbose output is on, the listing is like
584 @samp{ar -tv @var{archive} @var{module}@dots{}}.
586 Output normally goes to the standard output stream; however, if you
587 specify @var{outputfile} as a final argument, @command{ar} directs the
591 Exit from @command{ar}, with a @code{0} exit code to indicate successful
592 completion. This command does not save the output file; if you have
593 changed the current archive since the last @code{SAVE} command, those
596 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
597 Extract each named @var{module} from the current archive, writing them
598 into the current directory as separate files. Equivalent to @samp{ar -x
599 @var{archive} @var{module}@dots{}}.
601 Requires prior use of @code{OPEN} or @code{CREATE}.
604 @c FIXME Tokens but no commands???
611 Display full contents of the current archive, in ``verbose'' style
612 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
613 tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
614 enhancement, rather than present for MRI compatibility.)
616 Requires prior use of @code{OPEN} or @code{CREATE}.
618 @item OPEN @var{archive}
619 Opens an existing archive for use as the current archive (required for
620 many other commands). Any changes as the result of subsequent commands
621 will not actually affect @var{archive} until you next use @code{SAVE}.
623 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
624 In the current archive, replace each existing @var{module} (named in
625 the @code{REPLACE} arguments) from files in the current working directory.
626 To execute this command without errors, both the file, and the module in
627 the current archive, must exist.
629 Requires prior use of @code{OPEN} or @code{CREATE}.
632 Toggle an internal flag governing the output from @code{DIRECTORY}.
633 When the flag is on, @code{DIRECTORY} output matches output from
634 @samp{ar -tv }@dots{}.
637 Commit your changes to the current archive, and actually save it as a
638 file with the name specified in the last @code{CREATE} or @code{OPEN}
641 Requires prior use of @code{OPEN} or @code{CREATE}.
650 The @sc{gnu} linker @command{ld} is now described in a separate manual.
651 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
659 @c man title nm list symbols from object files
662 @c man begin SYNOPSIS nm
663 nm [@option{-a}|@option{--debug-syms}] [@option{-g}|@option{--extern-only}]
664 [@option{-B}] [@option{-C}|@option{--demangle}[=@var{style}]] [@option{-D}|@option{--dynamic}]
665 [@option{-S}|@option{--print-size}] [@option{-s}|@option{--print-armap}]
666 [@option{-A}|@option{-o}|@option{--print-file-name}]
667 [@option{-n}|@option{-v}|@option{--numeric-sort}] [@option{-p}|@option{--no-sort}]
668 [@option{-r}|@option{--reverse-sort}] [@option{--size-sort}] [@option{-u}|@option{--undefined-only}]
669 [@option{-t} @var{radix}|@option{--radix=}@var{radix}] [@option{-P}|@option{--portability}]
670 [@option{--target=}@var{bfdname}] [@option{-f}@var{format}|@option{--format=}@var{format}]
671 [@option{--defined-only}] [@option{-l}|@option{--line-numbers}] [@option{--no-demangle}]
672 [@option{-V}|@option{--version}] [@option{-X 32_64}] [@option{--help}] [@var{objfile}@dots{}]
676 @c man begin DESCRIPTION nm
677 @sc{gnu} @command{nm} lists the symbols from object files @var{objfile}@dots{}.
678 If no object files are listed as arguments, @command{nm} assumes the file
681 For each symbol, @command{nm} shows:
685 The symbol value, in the radix selected by options (see below), or
686 hexadecimal by default.
689 The symbol type. At least the following types are used; others are, as
690 well, depending on the object file format. If lowercase, the symbol is
691 local; if uppercase, the symbol is global (external).
693 @c Some more detail on exactly what these symbol types are used for
697 The symbol's value is absolute, and will not be changed by further
701 The symbol is in the uninitialized data section (known as BSS).
704 The symbol is common. Common symbols are uninitialized data. When
705 linking, multiple common symbols may appear with the same name. If the
706 symbol is defined anywhere, the common symbols are treated as undefined
709 For more details on common symbols, see the discussion of
710 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
714 The symbol is in the initialized data section.
717 The symbol is in an initialized data section for small objects. Some
718 object file formats permit more efficient access to small data objects,
719 such as a global int variable as opposed to a large global array.
722 The symbol is an indirect reference to another symbol. This is a @sc{gnu}
723 extension to the a.out object file format which is rarely used.
726 The symbol is a debugging symbol.
729 The symbol is in a read only data section.
732 The symbol is in an uninitialized data section for small objects.
735 The symbol is in the text (code) section.
738 The symbol is undefined.
741 The symbol is a weak object. When a weak defined symbol is linked with
742 a normal defined symbol, the normal defined symbol is used with no error.
743 When a weak undefined symbol is linked and the symbol is not defined,
744 the value of the weak symbol becomes zero with no error.
747 The symbol is a weak symbol that has not been specifically tagged as a
748 weak object symbol. When a weak defined symbol is linked with a normal
749 defined symbol, the normal defined symbol is used with no error.
750 When a weak undefined symbol is linked and the symbol is not defined,
751 the value of the weak symbol becomes zero with no error.
754 The symbol is a stabs symbol in an a.out object file. In this case, the
755 next values printed are the stabs other field, the stabs desc field, and
756 the stab type. Stabs symbols are used to hold debugging information.
758 For more information, see @ref{Top,Stabs,Stabs Overview,stabs.info, The
759 ``stabs'' debug format}.
763 The symbol type is unknown, or object file format specific.
772 @c man begin OPTIONS nm
773 The long and short forms of options, shown here as alternatives, are
779 @itemx --print-file-name
780 @cindex input file name
782 @cindex source file name
783 Precede each symbol by the name of the input file (or archive member)
784 in which it was found, rather than identifying the input file once only,
785 before all of its symbols.
789 @cindex debugging symbols
790 Display all symbols, even debugger-only symbols; normally these are not
794 @cindex @command{nm} format
795 @cindex @command{nm} compatibility
796 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
799 @itemx --demangle[=@var{style}]
800 @cindex demangling in nm
801 Decode (@dfn{demangle}) low-level symbol names into user-level names.
802 Besides removing any initial underscore prepended by the system, this
803 makes C++ function names readable. Different compilers have different
804 mangling styles. The optional demangling style argument can be used to
805 choose an appropriate demangling style for your compiler. @xref{c++filt},
806 for more information on demangling.
809 Do not demangle low-level symbol names. This is the default.
813 @cindex dynamic symbols
814 Display the dynamic symbols rather than the normal symbols. This is
815 only meaningful for dynamic objects, such as certain types of shared
818 @item -f @var{format}
819 @itemx --format=@var{format}
820 @cindex @command{nm} format
821 @cindex @command{nm} compatibility
822 Use the output format @var{format}, which can be @code{bsd},
823 @code{sysv}, or @code{posix}. The default is @code{bsd}.
824 Only the first character of @var{format} is significant; it can be
825 either upper or lower case.
829 @cindex external symbols
830 Display only external symbols.
833 @itemx --line-numbers
834 @cindex symbol line numbers
835 For each symbol, use debugging information to try to find a filename and
836 line number. For a defined symbol, look for the line number of the
837 address of the symbol. For an undefined symbol, look for the line
838 number of a relocation entry which refers to the symbol. If line number
839 information can be found, print it after the other symbol information.
843 @itemx --numeric-sort
844 Sort symbols numerically by their addresses, rather than alphabetically
849 @cindex sorting symbols
850 Do not bother to sort the symbols in any order; print them in the order
855 Use the POSIX.2 standard output format instead of the default format.
856 Equivalent to @samp{-f posix}.
860 Print size, not the value, of defined symbols for the @code{bsd} output format.
864 @cindex symbol index, listing
865 When listing symbols from archive members, include the index: a mapping
866 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
867 contain definitions for which names.
870 @itemx --reverse-sort
871 Reverse the order of the sort (whether numeric or alphabetic); let the
875 Sort symbols by size. The size is computed as the difference between
876 the value of the symbol and the value of the symbol with the next higher
877 value. If the @code{bsd} output format is used the size of the symbol
878 is printed, rather than the value, and @samp{-S} must be used in order
879 both size and value to be printed.
882 @itemx --radix=@var{radix}
883 Use @var{radix} as the radix for printing the symbol values. It must be
884 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
886 @item --target=@var{bfdname}
887 @cindex object code format
888 Specify an object code format other than your system's default format.
889 @xref{Target Selection}, for more information.
892 @itemx --undefined-only
893 @cindex external symbols
894 @cindex undefined symbols
895 Display only undefined symbols (those external to each object file).
898 @cindex external symbols
899 @cindex undefined symbols
900 Display only defined symbols for each object file.
904 Show the version number of @command{nm} and exit.
907 This option is ignored for compatibility with the AIX version of
908 @command{nm}. It takes one parameter which must be the string
909 @option{32_64}. The default mode of AIX @command{nm} corresponds
910 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
913 Show a summary of the options to @command{nm} and exit.
919 @c man begin SEEALSO nm
920 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
927 @c man title objcopy copy and translate object files
930 @c man begin SYNOPSIS objcopy
931 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
932 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
933 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
934 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
935 [@option{-S}|@option{--strip-all}] [@option{-g}|@option{--strip-debug}]
936 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
937 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
938 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
939 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
940 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
941 [@option{-x}|@option{--discard-all}] [@option{-X}|@option{--discard-locals}]
942 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
943 [@option{-i} @var{interleave}|@option{--interleave=}@var{interleave}]
944 [@option{-j} @var{sectionname}|@option{--only-section=}@var{sectionname}]
945 [@option{-R} @var{sectionname}|@option{--remove-section=}@var{sectionname}]
946 [@option{-p}|@option{--preserve-dates}]
947 [@option{--debugging}]
948 [@option{--gap-fill=}@var{val}] [@option{--pad-to=}@var{address}]
949 [@option{--set-start=}@var{val}] [@option{--adjust-start=}@var{incr}]
950 [@option{--change-addresses=}@var{incr}]
951 [@option{--change-section-address} @var{section}@{=,+,-@}@var{val}]
952 [@option{--change-section-lma} @var{section}@{=,+,-@}@var{val}]
953 [@option{--change-section-vma} @var{section}@{=,+,-@}@var{val}]
954 [@option{--change-warnings}] [@option{--no-change-warnings}]
955 [@option{--set-section-flags} @var{section}=@var{flags}]
956 [@option{--add-section} @var{sectionname}=@var{filename}]
957 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
958 [@option{--change-leading-char} ] [@option{--remove-leading-char}]
959 [@option{--srec-len=}@var{ival} ] [@option{--srec-forceS3}]
960 [@option{--redefine-sym} @var{old}=@var{new} ]
962 [@option{--keep-symbols=}@var{filename}]
963 [@option{--strip-symbols=}@var{filename}]
964 [@option{--keep-global-symbols=}@var{filename}]
965 [@option{--localize-symbols=}@var{filename}]
966 [@option{--weaken-symbols=}@var{filename}]
967 [@option{--alt-machine-code=}@var{index}]
968 [@option{--prefix-symbols=}@var{string}]
969 [@option{--prefix-sections=}@var{string}]
970 [@option{--prefix-alloc-sections=}@var{string}]
971 [@option{-v}|@option{--verbose}]
972 [@option{-V}|@option{--version}]
973 [@option{--help}] [@option{--info}]
974 @var{infile} [@var{outfile}]
978 @c man begin DESCRIPTION objcopy
979 The @sc{gnu} @command{objcopy} utility copies the contents of an object
980 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
981 read and write the object files. It can write the destination object
982 file in a format different from that of the source object file. The
983 exact behavior of @command{objcopy} is controlled by command-line options.
984 Note that @command{objcopy} should be able to copy a fully linked file
985 between any two formats. However, copying a relocatable object file
986 between any two formats may not work as expected.
988 @command{objcopy} creates temporary files to do its translations and
989 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
990 translation work; it has access to all the formats described in @sc{bfd}
991 and thus is able to recognize most formats without being told
992 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
994 @command{objcopy} can be used to generate S-records by using an output
995 target of @samp{srec} (e.g., use @samp{-O srec}).
997 @command{objcopy} can be used to generate a raw binary file by using an
998 output target of @samp{binary} (e.g., use @option{-O binary}). When
999 @command{objcopy} generates a raw binary file, it will essentially produce
1000 a memory dump of the contents of the input object file. All symbols and
1001 relocation information will be discarded. The memory dump will start at
1002 the load address of the lowest section copied into the output file.
1004 When generating an S-record or a raw binary file, it may be helpful to
1005 use @option{-S} to remove sections containing debugging information. In
1006 some cases @option{-R} will be useful to remove sections which contain
1007 information that is not needed by the binary file.
1009 Note---@command{objcopy} is not able to change the endianness of its input
1010 files. If the input format has an endianness (some formats do not),
1011 @command{objcopy} can only copy the inputs into file formats that have the
1012 same endianness or which have no endianness (e.g., @samp{srec}).
1016 @c man begin OPTIONS objcopy
1020 @itemx @var{outfile}
1021 The input and output files, respectively.
1022 If you do not specify @var{outfile}, @command{objcopy} creates a
1023 temporary file and destructively renames the result with
1024 the name of @var{infile}.
1026 @item -I @var{bfdname}
1027 @itemx --input-target=@var{bfdname}
1028 Consider the source file's object format to be @var{bfdname}, rather than
1029 attempting to deduce it. @xref{Target Selection}, for more information.
1031 @item -O @var{bfdname}
1032 @itemx --output-target=@var{bfdname}
1033 Write the output file using the object format @var{bfdname}.
1034 @xref{Target Selection}, for more information.
1036 @item -F @var{bfdname}
1037 @itemx --target=@var{bfdname}
1038 Use @var{bfdname} as the object format for both the input and the output
1039 file; i.e., simply transfer data from source to destination with no
1040 translation. @xref{Target Selection}, for more information.
1042 @item -B @var{bfdarch}
1043 @itemx --binary-architecture=@var{bfdarch}
1044 Useful when transforming a raw binary input file into an object file.
1045 In this case the output architecture can be set to @var{bfdarch}. This
1046 option will be ignored if the input file has a known @var{bfdarch}. You
1047 can access this binary data inside a program by referencing the special
1048 symbols that are created by the conversion process. These symbols are
1049 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1050 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1051 an object file and then access it in your code using these symbols.
1053 @item -j @var{sectionname}
1054 @itemx --only-section=@var{sectionname}
1055 Copy only the named section from the input file to the output file.
1056 This option may be given more than once. Note that using this option
1057 inappropriately may make the output file unusable.
1059 @item -R @var{sectionname}
1060 @itemx --remove-section=@var{sectionname}
1061 Remove any section named @var{sectionname} from the output file. This
1062 option may be given more than once. Note that using this option
1063 inappropriately may make the output file unusable.
1067 Do not copy relocation and symbol information from the source file.
1070 @itemx --strip-debug
1071 Do not copy debugging symbols from the source file.
1073 @item --strip-unneeded
1074 Strip all symbols that are not needed for relocation processing.
1076 @item -K @var{symbolname}
1077 @itemx --keep-symbol=@var{symbolname}
1078 Copy only symbol @var{symbolname} from the source file. This option may
1079 be given more than once.
1081 @item -N @var{symbolname}
1082 @itemx --strip-symbol=@var{symbolname}
1083 Do not copy symbol @var{symbolname} from the source file. This option
1084 may be given more than once.
1086 @item -G @var{symbolname}
1087 @itemx --keep-global-symbol=@var{symbolname}
1088 Keep only symbol @var{symbolname} global. Make all other symbols local
1089 to the file, so that they are not visible externally. This option may
1090 be given more than once.
1092 @item -L @var{symbolname}
1093 @itemx --localize-symbol=@var{symbolname}
1094 Make symbol @var{symbolname} local to the file, so that it is not
1095 visible externally. This option may be given more than once.
1097 @item -W @var{symbolname}
1098 @itemx --weaken-symbol=@var{symbolname}
1099 Make symbol @var{symbolname} weak. This option may be given more than once.
1102 @itemx --discard-all
1103 Do not copy non-global symbols from the source file.
1104 @c FIXME any reason to prefer "non-global" to "local" here?
1107 @itemx --discard-locals
1108 Do not copy compiler-generated local symbols.
1109 (These usually start with @samp{L} or @samp{.}.)
1112 @itemx --byte=@var{byte}
1113 Keep only every @var{byte}th byte of the input file (header data is not
1114 affected). @var{byte} can be in the range from 0 to @var{interleave}-1,
1115 where @var{interleave} is given by the @option{-i} or @option{--interleave}
1116 option, or the default of 4. This option is useful for creating files
1117 to program @sc{rom}. It is typically used with an @code{srec} output
1120 @item -i @var{interleave}
1121 @itemx --interleave=@var{interleave}
1122 Only copy one out of every @var{interleave} bytes. Select which byte to
1123 copy with the @option{-b} or @option{--byte} option. The default is 4.
1124 @command{objcopy} ignores this option if you do not specify either @option{-b} or
1128 @itemx --preserve-dates
1129 Set the access and modification dates of the output file to be the same
1130 as those of the input file.
1133 Convert debugging information, if possible. This is not the default
1134 because only certain debugging formats are supported, and the
1135 conversion process can be time consuming.
1137 @item --gap-fill @var{val}
1138 Fill gaps between sections with @var{val}. This operation applies to
1139 the @emph{load address} (LMA) of the sections. It is done by increasing
1140 the size of the section with the lower address, and filling in the extra
1141 space created with @var{val}.
1143 @item --pad-to @var{address}
1144 Pad the output file up to the load address @var{address}. This is
1145 done by increasing the size of the last section. The extra space is
1146 filled in with the value specified by @option{--gap-fill} (default zero).
1148 @item --set-start @var{val}
1149 Set the start address of the new file to @var{val}. Not all object file
1150 formats support setting the start address.
1152 @item --change-start @var{incr}
1153 @itemx --adjust-start @var{incr}
1154 @cindex changing start address
1155 Change the start address by adding @var{incr}. Not all object file
1156 formats support setting the start address.
1158 @item --change-addresses @var{incr}
1159 @itemx --adjust-vma @var{incr}
1160 @cindex changing object addresses
1161 Change the VMA and LMA addresses of all sections, as well as the start
1162 address, by adding @var{incr}. Some object file formats do not permit
1163 section addresses to be changed arbitrarily. Note that this does not
1164 relocate the sections; if the program expects sections to be loaded at a
1165 certain address, and this option is used to change the sections such
1166 that they are loaded at a different address, the program may fail.
1168 @item --change-section-address @var{section}@{=,+,-@}@var{val}
1169 @itemx --adjust-section-vma @var{section}@{=,+,-@}@var{val}
1170 @cindex changing section address
1171 Set or change both the VMA address and the LMA address of the named
1172 @var{section}. If @samp{=} is used, the section address is set to
1173 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1174 section address. See the comments under @option{--change-addresses},
1175 above. If @var{section} does not exist in the input file, a warning will
1176 be issued, unless @option{--no-change-warnings} is used.
1178 @item --change-section-lma @var{section}@{=,+,-@}@var{val}
1179 @cindex changing section LMA
1180 Set or change the LMA address of the named @var{section}. The LMA
1181 address is the address where the section will be loaded into memory at
1182 program load time. Normally this is the same as the VMA address, which
1183 is the address of the section at program run time, but on some systems,
1184 especially those where a program is held in ROM, the two can be
1185 different. If @samp{=} is used, the section address is set to
1186 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1187 section address. See the comments under @option{--change-addresses},
1188 above. If @var{section} does not exist in the input file, a warning
1189 will be issued, unless @option{--no-change-warnings} is used.
1191 @item --change-section-vma @var{section}@{=,+,-@}@var{val}
1192 @cindex changing section VMA
1193 Set or change the VMA address of the named @var{section}. The VMA
1194 address is the address where the section will be located once the
1195 program has started executing. Normally this is the same as the LMA
1196 address, which is the address where the section will be loaded into
1197 memory, but on some systems, especially those where a program is held in
1198 ROM, the two can be different. If @samp{=} is used, the section address
1199 is set to @var{val}. Otherwise, @var{val} is added to or subtracted
1200 from the section address. See the comments under
1201 @option{--change-addresses}, above. If @var{section} does not exist in
1202 the input file, a warning will be issued, unless
1203 @option{--no-change-warnings} is used.
1205 @item --change-warnings
1206 @itemx --adjust-warnings
1207 If @option{--change-section-address} or @option{--change-section-lma} or
1208 @option{--change-section-vma} is used, and the named section does not
1209 exist, issue a warning. This is the default.
1211 @item --no-change-warnings
1212 @itemx --no-adjust-warnings
1213 Do not issue a warning if @option{--change-section-address} or
1214 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1215 if the named section does not exist.
1217 @item --set-section-flags @var{section}=@var{flags}
1218 Set the flags for the named section. The @var{flags} argument is a
1219 comma separated string of flag names. The recognized names are
1220 @samp{alloc}, @samp{contents}, @samp{load}, @samp{noload},
1221 @samp{readonly}, @samp{code}, @samp{data}, @samp{rom}, @samp{share}, and
1222 @samp{debug}. You can set the @samp{contents} flag for a section which
1223 does not have contents, but it is not meaningful to clear the
1224 @samp{contents} flag of a section which does have contents--just remove
1225 the section instead. Not all flags are meaningful for all object file
1228 @item --add-section @var{sectionname}=@var{filename}
1229 Add a new section named @var{sectionname} while copying the file. The
1230 contents of the new section are taken from the file @var{filename}. The
1231 size of the section will be the size of the file. This option only
1232 works on file formats which can support sections with arbitrary names.
1234 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1235 Rename a section from @var{oldname} to @var{newname}, optionally
1236 changing the section's flags to @var{flags} in the process. This has
1237 the advantage over usng a linker script to perform the rename in that
1238 the output stays as an object file and does not become a linked
1241 This option is particularly helpful when the input format is binary,
1242 since this will always create a section called .data. If for example,
1243 you wanted instead to create a section called .rodata containing binary
1244 data you could use the following command line to achieve it:
1247 objcopy -I binary -O <output_format> -B <architecture> \
1248 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1249 <input_binary_file> <output_object_file>
1252 @item --change-leading-char
1253 Some object file formats use special characters at the start of
1254 symbols. The most common such character is underscore, which compilers
1255 often add before every symbol. This option tells @command{objcopy} to
1256 change the leading character of every symbol when it converts between
1257 object file formats. If the object file formats use the same leading
1258 character, this option has no effect. Otherwise, it will add a
1259 character, or remove a character, or change a character, as
1262 @item --remove-leading-char
1263 If the first character of a global symbol is a special symbol leading
1264 character used by the object file format, remove the character. The
1265 most common symbol leading character is underscore. This option will
1266 remove a leading underscore from all global symbols. This can be useful
1267 if you want to link together objects of different file formats with
1268 different conventions for symbol names. This is different from
1269 @option{--change-leading-char} because it always changes the symbol name
1270 when appropriate, regardless of the object file format of the output
1273 @item --srec-len=@var{ival}
1274 Meaningful only for srec output. Set the maximum length of the Srecords
1275 being produced to @var{ival}. This length covers both address, data and
1278 @item --srec-forceS3
1279 Meaningful only for srec output. Avoid generation of S1/S2 records,
1280 creating S3-only record format.
1282 @item --redefine-sym @var{old}=@var{new}
1283 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1284 when one is trying link two things together for which you have no
1285 source, and there are name collisions.
1288 Change all global symbols in the file to be weak. This can be useful
1289 when building an object which will be linked against other objects using
1290 the @option{-R} option to the linker. This option is only effective when
1291 using an object file format which supports weak symbols.
1293 @item --keep-symbols=@var{filename}
1294 Apply @option{--keep-symbol} option to each symbol listed in the file
1295 @var{filename}. @var{filename} is simply a flat file, with one symbol
1296 name per line. Line comments may be introduced by the hash character.
1297 This option may be given more than once.
1299 @item --strip-symbols=@var{filename}
1300 Apply @option{--strip-symbol} option to each symbol listed in the file
1301 @var{filename}. @var{filename} is simply a flat file, with one symbol
1302 name per line. Line comments may be introduced by the hash character.
1303 This option may be given more than once.
1305 @item --keep-global-symbols=@var{filename}
1306 Apply @option{--keep-global-symbol} option to each symbol listed in the
1307 file @var{filename}. @var{filename} is simply a flat file, with one
1308 symbol name per line. Line comments may be introduced by the hash
1309 character. This option may be given more than once.
1311 @item --localize-symbols=@var{filename}
1312 Apply @option{--localize-symbol} option to each symbol listed in the file
1313 @var{filename}. @var{filename} is simply a flat file, with one symbol
1314 name per line. Line comments may be introduced by the hash character.
1315 This option may be given more than once.
1317 @item --weaken-symbols=@var{filename}
1318 Apply @option{--weaken-symbol} option to each symbol listed in the file
1319 @var{filename}. @var{filename} is simply a flat file, with one symbol
1320 name per line. Line comments may be introduced by the hash character.
1321 This option may be given more than once.
1323 @item --alt-machine-code=@var{index}
1324 If the output architecture has alternate machine codes, use the
1325 @var{index}th code instead of the default one. This is useful in case
1326 a machine is assigned an official code and the tool-chain adopts the
1327 new code, but other applications still depend on the original code
1330 @item --prefix-symbols=@var{string}
1331 Prefix all symbols in the output file with @var{string}.
1333 @item --prefix-sections=@var{string}
1334 Prefix all section names in the output file with @var{string}.
1336 @item --prefix-alloc-sections=@var{string}
1337 Prefix all the names of all allocated sections in the output file with
1342 Show the version number of @command{objcopy}.
1346 Verbose output: list all object files modified. In the case of
1347 archives, @samp{objcopy -V} lists all members of the archive.
1350 Show a summary of the options to @command{objcopy}.
1353 Display a list showing all architectures and object formats available.
1359 @c man begin SEEALSO objcopy
1360 ld(1), objdump(1), and the Info entries for @file{binutils}.
1367 @cindex object file information
1370 @c man title objdump display information from object files.
1373 @c man begin SYNOPSIS objdump
1374 objdump [@option{-a}|@option{--archive-headers}]
1375 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
1376 [@option{-C}|@option{--demangle}[=@var{style}] ]
1377 [@option{-d}|@option{--disassemble}]
1378 [@option{-D}|@option{--disassemble-all}]
1379 [@option{-z}|@option{--disassemble-zeroes}]
1380 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
1381 [@option{-f}|@option{--file-headers}]
1382 [@option{--file-start-context}]
1383 [@option{-g}|@option{--debugging}]
1384 [@option{-h}|@option{--section-headers}|@option{--headers}]
1385 [@option{-i}|@option{--info}]
1386 [@option{-j} @var{section}|@option{--section=}@var{section}]
1387 [@option{-l}|@option{--line-numbers}]
1388 [@option{-S}|@option{--source}]
1389 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
1390 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
1391 [@option{-p}|@option{--private-headers}]
1392 [@option{-r}|@option{--reloc}]
1393 [@option{-R}|@option{--dynamic-reloc}]
1394 [@option{-s}|@option{--full-contents}]
1395 [@option{-G}|@option{--stabs}]
1396 [@option{-t}|@option{--syms}]
1397 [@option{-T}|@option{--dynamic-syms}]
1398 [@option{-x}|@option{--all-headers}]
1399 [@option{-w}|@option{--wide}]
1400 [@option{--start-address=}@var{address}]
1401 [@option{--stop-address=}@var{address}]
1402 [@option{--prefix-addresses}]
1403 [@option{--[no-]show-raw-insn}]
1404 [@option{--adjust-vma=}@var{offset}]
1405 [@option{-V}|@option{--version}]
1406 [@option{-H}|@option{--help}]
1407 @var{objfile}@dots{}
1411 @c man begin DESCRIPTION objdump
1413 @command{objdump} displays information about one or more object files.
1414 The options control what particular information to display. This
1415 information is mostly useful to programmers who are working on the
1416 compilation tools, as opposed to programmers who just want their
1417 program to compile and work.
1419 @var{objfile}@dots{} are the object files to be examined. When you
1420 specify archives, @command{objdump} shows information on each of the member
1425 @c man begin OPTIONS objdump
1427 The long and short forms of options, shown here as alternatives, are
1428 equivalent. At least one option from the list
1429 @option{-a,-d,-D,-f,-g,-G,-h,-H,-p,-r,-R,-S,-t,-T,-V,-x} must be given.
1433 @itemx --archive-header
1434 @cindex archive headers
1435 If any of the @var{objfile} files are archives, display the archive
1436 header information (in a format similar to @samp{ls -l}). Besides the
1437 information you could list with @samp{ar tv}, @samp{objdump -a} shows
1438 the object file format of each archive member.
1440 @item --adjust-vma=@var{offset}
1441 @cindex section addresses in objdump
1442 @cindex VMA in objdump
1443 When dumping information, first add @var{offset} to all the section
1444 addresses. This is useful if the section addresses do not correspond to
1445 the symbol table, which can happen when putting sections at particular
1446 addresses when using a format which can not represent section addresses,
1449 @item -b @var{bfdname}
1450 @itemx --target=@var{bfdname}
1451 @cindex object code format
1452 Specify that the object-code format for the object files is
1453 @var{bfdname}. This option may not be necessary; @var{objdump} can
1454 automatically recognize many formats.
1458 objdump -b oasys -m vax -h fu.o
1461 displays summary information from the section headers (@option{-h}) of
1462 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
1463 file in the format produced by Oasys compilers. You can list the
1464 formats available with the @option{-i} option.
1465 @xref{Target Selection}, for more information.
1468 @itemx --demangle[=@var{style}]
1469 @cindex demangling in objdump
1470 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1471 Besides removing any initial underscore prepended by the system, this
1472 makes C++ function names readable. Different compilers have different
1473 mangling styles. The optional demangling style argument can be used to
1474 choose an appropriate demangling style for your compiler. @xref{c++filt},
1475 for more information on demangling.
1479 Display debugging information. This attempts to parse debugging
1480 information stored in the file and print it out using a C like syntax.
1481 Only certain types of debugging information have been implemented.
1482 Some other types are supported by @command{readelf -w}.
1486 @itemx --disassemble
1487 @cindex disassembling object code
1488 @cindex machine instructions
1489 Display the assembler mnemonics for the machine instructions from
1490 @var{objfile}. This option only disassembles those sections which are
1491 expected to contain instructions.
1494 @itemx --disassemble-all
1495 Like @option{-d}, but disassemble the contents of all sections, not just
1496 those expected to contain instructions.
1498 @item --prefix-addresses
1499 When disassembling, print the complete address on each line. This is
1500 the older disassembly format.
1504 @itemx --endian=@{big|little@}
1506 @cindex disassembly endianness
1507 Specify the endianness of the object files. This only affects
1508 disassembly. This can be useful when disassembling a file format which
1509 does not describe endianness information, such as S-records.
1512 @itemx --file-headers
1513 @cindex object file header
1514 Display summary information from the overall header of
1515 each of the @var{objfile} files.
1517 @item --file-start-context
1518 @cindex source code context
1519 Specify that when displaying interlisted source code/disassembly
1520 (assumes @option{-S}) from a file that has not yet been displayed, extend the
1521 context to the start of the file.
1524 @itemx --section-headers
1526 @cindex section headers
1527 Display summary information from the section headers of the
1530 File segments may be relocated to nonstandard addresses, for example by
1531 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
1532 @command{ld}. However, some object file formats, such as a.out, do not
1533 store the starting address of the file segments. In those situations,
1534 although @command{ld} relocates the sections correctly, using @samp{objdump
1535 -h} to list the file section headers cannot show the correct addresses.
1536 Instead, it shows the usual addresses, which are implicit for the
1541 Print a summary of the options to @command{objdump} and exit.
1545 @cindex architectures available
1546 @cindex object formats available
1547 Display a list showing all architectures and object formats available
1548 for specification with @option{-b} or @option{-m}.
1551 @itemx --section=@var{name}
1552 @cindex section information
1553 Display information only for section @var{name}.
1556 @itemx --line-numbers
1557 @cindex source filenames for object files
1558 Label the display (using debugging information) with the filename and
1559 source line numbers corresponding to the object code or relocs shown.
1560 Only useful with @option{-d}, @option{-D}, or @option{-r}.
1562 @item -m @var{machine}
1563 @itemx --architecture=@var{machine}
1564 @cindex architecture
1565 @cindex disassembly architecture
1566 Specify the architecture to use when disassembling object files. This
1567 can be useful when disassembling object files which do not describe
1568 architecture information, such as S-records. You can list the available
1569 architectures with the @option{-i} option.
1571 @item -M @var{options}
1572 @itemx --disassembler-options=@var{options}
1573 Pass target specific information to the disassembler. Only supported on
1576 If the target is an ARM architecture then this switch can be used to
1577 select which register name set is used during disassembler. Specifying
1578 @option{-M reg-name-std} (the default) will select the register names as
1579 used in ARM's instruction set documentation, but with register 13 called
1580 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
1581 @option{-M reg-names-apcs} will select the name set used by the ARM
1582 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
1583 just use @samp{r} followed by the register number.
1585 There are also two variants on the APCS register naming scheme enabled
1586 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
1587 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
1588 with the normal register names or the special register names).
1590 This option can also be used for ARM architectures to force the
1591 disassembler to interpret all instructions as Thumb instructions by
1592 using the switch @option{--disassembler-options=force-thumb}. This can be
1593 useful when attempting to disassemble thumb code produced by other
1596 For the x86, some of the options duplicate functions of the @option{-m}
1597 switch, but allow finer grained control. Multiple selections from the
1598 following may be specified as a comma separated string.
1599 @option{x86-64}, @option{i386} and @option{i8086} select disassembly for
1600 the given architecture. @option{intel} and @option{att} select between
1601 intel syntax mode and AT&T syntax mode. @option{addr32},
1602 @option{addr16}, @option{data32} and @option{data16} specify the default
1603 address size and operand size. These four options will be overridden if
1604 @option{x86-64}, @option{i386} or @option{i8086} appear later in the
1605 option string. Lastly, @option{suffix}, when in AT&T mode,
1606 instructs the disassembler to print a mnemonic suffix even when the
1607 suffix could be inferred by the operands.
1609 For PPC, @option{booke}, @option{booke32} and @option{booke64} select
1610 disassembly of BookE instructions. @option{32} and @option{64} select
1611 PowerPC and PowerPC64 disassembly, respectively.
1613 For MIPS, this option controls the printing of register names in
1614 disassembled instructions. Multiple selections from the
1615 following may be specified as a comma separated string, and invalid
1616 options are ignored:
1619 @item gpr-names=@var{ABI}
1620 Print GPR (general-purpose register) names as appropriate
1621 for the specified ABI. By default, GPR names are selected according to
1622 the ABI of the binary being disassembled.
1624 @item fpr-names=@var{ABI}
1625 Print FPR (floating-point register) names as
1626 appropriate for the specified ABI. By default, FPR numbers are printed
1629 @item cp0-names=@var{ARCH}
1630 Print CP0 (system control coprocessor; coprocessor 0) register names
1631 as appropriate for the CPU or architecture specified by
1632 @var{ARCH}. By default, CP0 register names are selected according to
1633 the architecture and CPU of the binary being disassembled.
1635 @item hwr-names=@var{ARCH}
1636 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
1637 as appropriate for the CPU or architecture specified by
1638 @var{ARCH}. By default, HWR names are selected according to
1639 the architecture and CPU of the binary being disassembled.
1641 @item reg-names=@var{ABI}
1642 Print GPR and FPR names as appropriate for the selected ABI.
1644 @item reg-names=@var{ARCH}
1645 Print CPU-specific register names (CP0 register and HWR names)
1646 as appropriate for the selected CPU or architecture.
1649 For any of the options listed above, @var{ABI} or
1650 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
1651 rather than names, for the selected types of registers.
1652 You can list the available values of @var{ABI} and @var{ARCH} using
1653 the @option{--help} option.
1656 @itemx --private-headers
1657 Print information that is specific to the object file format. The exact
1658 information printed depends upon the object file format. For some
1659 object file formats, no additional information is printed.
1663 @cindex relocation entries, in object file
1664 Print the relocation entries of the file. If used with @option{-d} or
1665 @option{-D}, the relocations are printed interspersed with the
1669 @itemx --dynamic-reloc
1670 @cindex dynamic relocation entries, in object file
1671 Print the dynamic relocation entries of the file. This is only
1672 meaningful for dynamic objects, such as certain types of shared
1676 @itemx --full-contents
1677 @cindex sections, full contents
1678 @cindex object file sections
1679 Display the full contents of any sections requested.
1683 @cindex source disassembly
1684 @cindex disassembly, with source
1685 Display source code intermixed with disassembly, if possible. Implies
1688 @item --show-raw-insn
1689 When disassembling instructions, print the instruction in hex as well as
1690 in symbolic form. This is the default except when
1691 @option{--prefix-addresses} is used.
1693 @item --no-show-raw-insn
1694 When disassembling instructions, do not print the instruction bytes.
1695 This is the default when @option{--prefix-addresses} is used.
1701 @cindex debug symbols
1702 @cindex ELF object file format
1703 Display the full contents of any sections requested. Display the
1704 contents of the .stab and .stab.index and .stab.excl sections from an
1705 ELF file. This is only useful on systems (such as Solaris 2.0) in which
1706 @code{.stab} debugging symbol-table entries are carried in an ELF
1707 section. In most other file formats, debugging symbol-table entries are
1708 interleaved with linkage symbols, and are visible in the @option{--syms}
1711 For more information on stabs symbols, see @ref{Top,Stabs,Stabs
1712 Overview,stabs.info, The ``stabs'' debug format}.
1715 @item --start-address=@var{address}
1716 @cindex start-address
1717 Start displaying data at the specified address. This affects the output
1718 of the @option{-d}, @option{-r} and @option{-s} options.
1720 @item --stop-address=@var{address}
1721 @cindex stop-address
1722 Stop displaying data at the specified address. This affects the output
1723 of the @option{-d}, @option{-r} and @option{-s} options.
1727 @cindex symbol table entries, printing
1728 Print the symbol table entries of the file.
1729 This is similar to the information provided by the @samp{nm} program.
1732 @itemx --dynamic-syms
1733 @cindex dynamic symbol table entries, printing
1734 Print the dynamic symbol table entries of the file. This is only
1735 meaningful for dynamic objects, such as certain types of shared
1736 libraries. This is similar to the information provided by the @samp{nm}
1737 program when given the @option{-D} (@option{--dynamic}) option.
1741 Print the version number of @command{objdump} and exit.
1744 @itemx --all-headers
1745 @cindex all header information, object file
1746 @cindex header information, all
1747 Display all available header information, including the symbol table and
1748 relocation entries. Using @option{-x} is equivalent to specifying all of
1749 @option{-a -f -h -r -t}.
1753 @cindex wide output, printing
1754 Format some lines for output devices that have more than 80 columns.
1755 Also do not truncate symbol names when they are displayed.
1758 @itemx --disassemble-zeroes
1759 Normally the disassembly output will skip blocks of zeroes. This
1760 option directs the disassembler to disassemble those blocks, just like
1767 @c man begin SEEALSO objdump
1768 nm(1), readelf(1), and the Info entries for @file{binutils}.
1776 @cindex archive contents
1777 @cindex symbol index
1779 @c man title ranlib generate index to archive.
1782 @c man begin SYNOPSIS ranlib
1783 ranlib [@option{-vV}] @var{archive}
1787 @c man begin DESCRIPTION ranlib
1789 @command{ranlib} generates an index to the contents of an archive and
1790 stores it in the archive. The index lists each symbol defined by a
1791 member of an archive that is a relocatable object file.
1793 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
1795 An archive with such an index speeds up linking to the library and
1796 allows routines in the library to call each other without regard to
1797 their placement in the archive.
1799 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
1800 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
1805 @c man begin OPTIONS ranlib
1811 Show the version number of @command{ranlib}.
1817 @c man begin SEEALSO ranlib
1818 ar(1), nm(1), and the Info entries for @file{binutils}.
1826 @cindex section sizes
1828 @c man title size list section sizes and total size.
1831 @c man begin SYNOPSIS size
1832 size [@option{-A}|@option{-B}|@option{--format=}@var{compatibility}]
1834 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
1835 [@option{-t}|@option{--totals}]
1836 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
1837 [@var{objfile}@dots{}]
1841 @c man begin DESCRIPTION size
1843 The @sc{gnu} @command{size} utility lists the section sizes---and the total
1844 size---for each of the object or archive files @var{objfile} in its
1845 argument list. By default, one line of output is generated for each
1846 object file or each module in an archive.
1848 @var{objfile}@dots{} are the object files to be examined.
1849 If none are specified, the file @code{a.out} will be used.
1853 @c man begin OPTIONS size
1855 The command line options have the following meanings:
1860 @itemx --format=@var{compatibility}
1861 @cindex @command{size} display format
1862 Using one of these options, you can choose whether the output from @sc{gnu}
1863 @command{size} resembles output from System V @command{size} (using @option{-A},
1864 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
1865 @option{--format=berkeley}). The default is the one-line format similar to
1867 @c Bonus for doc-source readers: you can also say --format=strange (or
1868 @c anything else that starts with 's') for sysv, and --format=boring (or
1869 @c anything else that starts with 'b') for Berkeley.
1871 Here is an example of the Berkeley (default) format of output from
1874 $ size --format=Berkeley ranlib size
1875 text data bss dec hex filename
1876 294880 81920 11592 388392 5ed28 ranlib
1877 294880 81920 11888 388688 5ee50 size
1881 This is the same data, but displayed closer to System V conventions:
1884 $ size --format=SysV ranlib size
1902 Show a summary of acceptable arguments and options.
1907 @itemx --radix=@var{number}
1908 @cindex @command{size} number format
1909 @cindex radix for section sizes
1910 Using one of these options, you can control whether the size of each
1911 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
1912 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
1913 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
1914 values (8, 10, 16) are supported. The total size is always given in two
1915 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
1916 octal and hexadecimal if you're using @option{-o}.
1920 Show totals of all objects listed (Berkeley format listing mode only).
1922 @item --target=@var{bfdname}
1923 @cindex object code format
1924 Specify that the object-code format for @var{objfile} is
1925 @var{bfdname}. This option may not be necessary; @command{size} can
1926 automatically recognize many formats.
1927 @xref{Target Selection}, for more information.
1931 Display the version number of @command{size}.
1937 @c man begin SEEALSO size
1938 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
1945 @cindex listings strings
1946 @cindex printing strings
1947 @cindex strings, printing
1949 @c man title strings print the strings of printable characters in files.
1952 @c man begin SYNOPSIS strings
1953 strings [@option{-afov}] [@option{-}@var{min-len}]
1954 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
1955 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
1956 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
1957 [@option{-}] [@option{--all}] [@option{--print-file-name}]
1958 [@option{--target=}@var{bfdname}]
1959 [@option{--help}] [@option{--version}] @var{file}@dots{}
1963 @c man begin DESCRIPTION strings
1965 For each @var{file} given, @sc{gnu} @command{strings} prints the printable
1966 character sequences that are at least 4 characters long (or the number
1967 given with the options below) and are followed by an unprintable
1968 character. By default, it only prints the strings from the initialized
1969 and loaded sections of object files; for other types of files, it prints
1970 the strings from the whole file.
1972 @command{strings} is mainly useful for determining the contents of non-text
1977 @c man begin OPTIONS strings
1983 Do not scan only the initialized and loaded sections of object files;
1984 scan the whole files.
1987 @itemx --print-file-name
1988 Print the name of the file before each string.
1991 Print a summary of the program usage on the standard output and exit.
1993 @item -@var{min-len}
1994 @itemx -n @var{min-len}
1995 @itemx --bytes=@var{min-len}
1996 Print sequences of characters that are at least @var{min-len} characters
1997 long, instead of the default 4.
2000 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
2001 act like @samp{-t d} instead. Since we can not be compatible with both
2002 ways, we simply chose one.
2004 @item -t @var{radix}
2005 @itemx --radix=@var{radix}
2006 Print the offset within the file before each string. The single
2007 character argument specifies the radix of the offset---@samp{o} for
2008 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
2010 @item -e @var{encoding}
2011 @itemx --encoding=@var{encoding}
2012 Select the character encoding of the strings that are to be found.
2013 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
2014 characters (ASCII, ISO 8859, etc., default), @samp{S} =
2015 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
2016 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
2017 littleendian. Useful for finding wide character strings.
2019 @item --target=@var{bfdname}
2020 @cindex object code format
2021 Specify an object code format other than your system's default format.
2022 @xref{Target Selection}, for more information.
2026 Print the program version number on the standard output and exit.
2032 @c man begin SEEALSO strings
2033 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
2034 and the Info entries for @file{binutils}.
2042 @cindex removing symbols
2043 @cindex discarding symbols
2044 @cindex symbols, discarding
2046 @c man title strip Discard symbols from object files.
2049 @c man begin SYNOPSIS strip
2050 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname} ]
2051 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname} ]
2052 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname} ]
2053 [@option{-s}|@option{--strip-all}] [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
2054 [@option{-K} @var{symbolname} |@option{--keep-symbol=}@var{symbolname} ]
2055 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname} ]
2056 [@option{-x}|@option{--discard-all} ] [@option{-X} |@option{--discard-locals}]
2057 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname} ]
2058 [@option{-o} @var{file} ] [@option{-p}|@option{--preserve-dates}]
2059 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
2060 [@option{--help}] [@option{--info}]
2061 @var{objfile}@dots{}
2065 @c man begin DESCRIPTION strip
2067 @sc{gnu} @command{strip} discards all symbols from object files
2068 @var{objfile}. The list of object files may include archives.
2069 At least one object file must be given.
2071 @command{strip} modifies the files named in its argument,
2072 rather than writing modified copies under different names.
2076 @c man begin OPTIONS strip
2079 @item -F @var{bfdname}
2080 @itemx --target=@var{bfdname}
2081 Treat the original @var{objfile} as a file with the object
2082 code format @var{bfdname}, and rewrite it in the same format.
2083 @xref{Target Selection}, for more information.
2086 Show a summary of the options to @command{strip} and exit.
2089 Display a list showing all architectures and object formats available.
2091 @item -I @var{bfdname}
2092 @itemx --input-target=@var{bfdname}
2093 Treat the original @var{objfile} as a file with the object
2094 code format @var{bfdname}.
2095 @xref{Target Selection}, for more information.
2097 @item -O @var{bfdname}
2098 @itemx --output-target=@var{bfdname}
2099 Replace @var{objfile} with a file in the output format @var{bfdname}.
2100 @xref{Target Selection}, for more information.
2102 @item -R @var{sectionname}
2103 @itemx --remove-section=@var{sectionname}
2104 Remove any section named @var{sectionname} from the output file. This
2105 option may be given more than once. Note that using this option
2106 inappropriately may make the output file unusable.
2115 @itemx --strip-debug
2116 Remove debugging symbols only.
2118 @item --strip-unneeded
2119 Remove all symbols that are not needed for relocation processing.
2121 @item -K @var{symbolname}
2122 @itemx --keep-symbol=@var{symbolname}
2123 Keep only symbol @var{symbolname} from the source file. This option may
2124 be given more than once.
2126 @item -N @var{symbolname}
2127 @itemx --strip-symbol=@var{symbolname}
2128 Remove symbol @var{symbolname} from the source file. This option may be
2129 given more than once, and may be combined with strip options other than
2133 Put the stripped output in @var{file}, rather than replacing the
2134 existing file. When this argument is used, only one @var{objfile}
2135 argument may be specified.
2138 @itemx --preserve-dates
2139 Preserve the access and modification dates of the file.
2142 @itemx --discard-all
2143 Remove non-global symbols.
2146 @itemx --discard-locals
2147 Remove compiler-generated local symbols.
2148 (These usually start with @samp{L} or @samp{.}.)
2152 Show the version number for @command{strip}.
2156 Verbose output: list all object files modified. In the case of
2157 archives, @samp{strip -v} lists all members of the archive.
2163 @c man begin SEEALSO strip
2164 the Info entries for @file{binutils}.
2168 @node c++filt, addr2line, strip, Top
2172 @cindex demangling C++ symbols
2174 @c man title cxxfilt Demangle C++ and Java symbols.
2177 @c man begin SYNOPSIS cxxfilt
2178 c++filt [@option{-_}|@option{--strip-underscores}]
2179 [@option{-j}|@option{--java}]
2180 [@option{-n}|@option{--no-strip-underscores}]
2181 [@option{-s} @var{format}|@option{--format=}@var{format}]
2182 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
2186 @c man begin DESCRIPTION cxxfilt
2189 The C++ and Java languages provides function overloading, which means
2190 that you can write many functions with the same name (providing each
2191 takes parameters of different types). All C++ and Java function names
2192 are encoded into a low-level assembly label (this process is known as
2193 @dfn{mangling}). The @command{c++filt}
2194 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
2195 MS-DOS this program is named @command{cxxfilt}.}
2196 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
2197 names into user-level names so that the linker can keep these overloaded
2198 functions from clashing.
2200 Every alphanumeric word (consisting of letters, digits, underscores,
2201 dollars, or periods) seen in the input is a potential label. If the
2202 label decodes into a C++ name, the C++ name replaces the low-level
2205 You can use @command{c++filt} to decipher individual symbols:
2208 c++filt @var{symbol}
2211 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
2212 names from the standard input and writes the demangled names to the
2213 standard output. All results are printed on the standard output.
2217 @c man begin OPTIONS cxxfilt
2221 @itemx --strip-underscores
2222 On some systems, both the C and C++ compilers put an underscore in front
2223 of every name. For example, the C name @code{foo} gets the low-level
2224 name @code{_foo}. This option removes the initial underscore. Whether
2225 @command{c++filt} removes the underscore by default is target dependent.
2229 Prints demangled names using Java syntax. The default is to use C++
2233 @itemx --no-strip-underscores
2234 Do not remove the initial underscore.
2236 @item -s @var{format}
2237 @itemx --format=@var{format}
2238 @command{c++filt} can decode various methods of mangling, used by
2239 different compilers. The argument to this option selects which
2244 Automatic selection based on executable (the default method)
2246 the one used by the @sc{gnu} C++ compiler (g++)
2248 the one used by the Lucid compiler (lcc)
2250 the one specified by the C++ Annotated Reference Manual
2252 the one used by the HP compiler (aCC)
2254 the one used by the EDG compiler
2256 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
2258 the one used by the @sc{gnu} Java compiler (gcj)
2260 the one used by the @sc{gnu} Ada compiler (GNAT).
2264 Print a summary of the options to @command{c++filt} and exit.
2267 Print the version number of @command{c++filt} and exit.
2273 @c man begin SEEALSO cxxfilt
2274 the Info entries for @file{binutils}.
2279 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
2280 user interface are subject to change in future releases. In particular,
2281 a command-line option may be required in the the future to decode a name
2282 passed as an argument on the command line; in other words,
2285 c++filt @var{symbol}
2289 may in a future release become
2292 c++filt @var{option} @var{symbol}
2300 @cindex address to file name and line number
2302 @c man title addr2line convert addresses into file names and line numbers.
2305 @c man begin SYNOPSIS addr2line
2306 addr2line [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
2307 [@option{-C}|@option{--demangle}[=@var{style}]]
2308 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
2309 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
2310 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
2315 @c man begin DESCRIPTION addr2line
2317 @command{addr2line} translates program addresses into file names and line
2318 numbers. Given an address and an executable, it uses the debugging
2319 information in the executable to figure out which file name and line
2320 number are associated with a given address.
2322 The executable to use is specified with the @option{-e} option. The
2323 default is the file @file{a.out}.
2325 @command{addr2line} has two modes of operation.
2327 In the first, hexadecimal addresses are specified on the command line,
2328 and @command{addr2line} displays the file name and line number for each
2331 In the second, @command{addr2line} reads hexadecimal addresses from
2332 standard input, and prints the file name and line number for each
2333 address on standard output. In this mode, @command{addr2line} may be used
2334 in a pipe to convert dynamically chosen addresses.
2336 The format of the output is @samp{FILENAME:LINENO}. The file name and
2337 line number for each address is printed on a separate line. If the
2338 @command{-f} option is used, then each @samp{FILENAME:LINENO} line is
2339 preceded by a @samp{FUNCTIONNAME} line which is the name of the function
2340 containing the address.
2342 If the file name or function name can not be determined,
2343 @command{addr2line} will print two question marks in their place. If the
2344 line number can not be determined, @command{addr2line} will print 0.
2348 @c man begin OPTIONS addr2line
2350 The long and short forms of options, shown here as alternatives, are
2354 @item -b @var{bfdname}
2355 @itemx --target=@var{bfdname}
2356 @cindex object code format
2357 Specify that the object-code format for the object files is
2361 @itemx --demangle[=@var{style}]
2362 @cindex demangling in objdump
2363 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2364 Besides removing any initial underscore prepended by the system, this
2365 makes C++ function names readable. Different compilers have different
2366 mangling styles. The optional demangling style argument can be used to
2367 choose an appropriate demangling style for your compiler. @xref{c++filt},
2368 for more information on demangling.
2370 @item -e @var{filename}
2371 @itemx --exe=@var{filename}
2372 Specify the name of the executable for which addresses should be
2373 translated. The default file is @file{a.out}.
2377 Display function names as well as file and line number information.
2381 Display only the base of each file name.
2387 @c man begin SEEALSO addr2line
2388 Info entries for @file{binutils}.
2395 @command{nlmconv} converts a relocatable object file into a NetWare
2399 @command{nlmconv} currently works with @samp{i386} object
2400 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
2401 object files in @sc{elf}, or @code{a.out} format@footnote{
2402 @command{nlmconv} should work with any @samp{i386} or @sc{sparc} object
2403 format in the Binary File Descriptor library. It has only been tested
2404 with the above formats.}.
2408 @emph{Warning:} @command{nlmconv} is not always built as part of the binary
2409 utilities, since it is only useful for NLM targets.
2412 @c man title nlmconv converts object code into an NLM.
2415 @c man begin SYNOPSIS nlmconv
2416 nlmconv [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
2417 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
2418 [@option{-T} @var{headerfile}|@option{--header-file=}@var{headerfile}]
2419 [@option{-d}|@option{--debug}] [@option{-l} @var{linker}|@option{--linker=}@var{linker}]
2420 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
2421 @var{infile} @var{outfile}
2425 @c man begin DESCRIPTION nlmconv
2427 @command{nlmconv} converts the relocatable @samp{i386} object file
2428 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
2429 reading @var{headerfile} for NLM header information. For instructions
2430 on writing the NLM command file language used in header files, see the
2431 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
2432 Development and Tools Overview}, which is part of the NLM Software
2433 Developer's Kit (``NLM SDK''), available from Novell, Inc.
2434 @command{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
2437 see @ref{BFD,,BFD,ld.info,Using LD}, for more information.
2440 @command{nlmconv} can perform a link step. In other words, you can list
2441 more than one object file for input if you list them in the definitions
2442 file (rather than simply specifying one input file on the command line).
2443 In this case, @command{nlmconv} calls the linker for you.
2447 @c man begin OPTIONS nlmconv
2450 @item -I @var{bfdname}
2451 @itemx --input-target=@var{bfdname}
2452 Object format of the input file. @command{nlmconv} can usually determine
2453 the format of a given file (so no default is necessary).
2454 @xref{Target Selection}, for more information.
2456 @item -O @var{bfdname}
2457 @itemx --output-target=@var{bfdname}
2458 Object format of the output file. @command{nlmconv} infers the output
2459 format based on the input format, e.g. for a @samp{i386} input file the
2460 output format is @samp{nlm32-i386}.
2461 @xref{Target Selection}, for more information.
2463 @item -T @var{headerfile}
2464 @itemx --header-file=@var{headerfile}
2465 Reads @var{headerfile} for NLM header information. For instructions on
2466 writing the NLM command file language used in header files, see@ see the
2467 @samp{linkers} section, of the @cite{NLM Development and Tools
2468 Overview}, which is part of the NLM Software Developer's Kit, available
2473 Displays (on standard error) the linker command line used by @command{nlmconv}.
2475 @item -l @var{linker}
2476 @itemx --linker=@var{linker}
2477 Use @var{linker} for any linking. @var{linker} can be an absolute or a
2482 Prints a usage summary.
2486 Prints the version number for @command{nlmconv}.
2492 @c man begin SEEALSO nlmconv
2493 the Info entries for @file{binutils}.
2500 @command{windres} may be used to manipulate Windows resources.
2503 @emph{Warning:} @command{windres} is not always built as part of the binary
2504 utilities, since it is only useful for Windows targets.
2507 @c man title windres manipulate Windows resources.
2510 @c man begin SYNOPSIS windres
2511 windres [options] [input-file] [output-file]
2515 @c man begin DESCRIPTION windres
2517 @command{windres} reads resources from an input file and copies them into
2518 an output file. Either file may be in one of three formats:
2522 A text format read by the Resource Compiler.
2525 A binary format generated by the Resource Compiler.
2528 A COFF object or executable.
2531 The exact description of these different formats is available in
2532 documentation from Microsoft.
2534 When @command{windres} converts from the @code{rc} format to the @code{res}
2535 format, it is acting like the Windows Resource Compiler. When
2536 @command{windres} converts from the @code{res} format to the @code{coff}
2537 format, it is acting like the Windows @code{CVTRES} program.
2539 When @command{windres} generates an @code{rc} file, the output is similar
2540 but not identical to the format expected for the input. When an input
2541 @code{rc} file refers to an external filename, an output @code{rc} file
2542 will instead include the file contents.
2544 If the input or output format is not specified, @command{windres} will
2545 guess based on the file name, or, for the input file, the file contents.
2546 A file with an extension of @file{.rc} will be treated as an @code{rc}
2547 file, a file with an extension of @file{.res} will be treated as a
2548 @code{res} file, and a file with an extension of @file{.o} or
2549 @file{.exe} will be treated as a @code{coff} file.
2551 If no output file is specified, @command{windres} will print the resources
2552 in @code{rc} format to standard output.
2554 The normal use is for you to write an @code{rc} file, use @command{windres}
2555 to convert it to a COFF object file, and then link the COFF file into
2556 your application. This will make the resources described in the
2557 @code{rc} file available to Windows.
2561 @c man begin OPTIONS windres
2564 @item -i @var{filename}
2565 @itemx --input @var{filename}
2566 The name of the input file. If this option is not used, then
2567 @command{windres} will use the first non-option argument as the input file
2568 name. If there are no non-option arguments, then @command{windres} will
2569 read from standard input. @command{windres} can not read a COFF file from
2572 @item -o @var{filename}
2573 @itemx --output @var{filename}
2574 The name of the output file. If this option is not used, then
2575 @command{windres} will use the first non-option argument, after any used
2576 for the input file name, as the output file name. If there is no
2577 non-option argument, then @command{windres} will write to standard output.
2578 @command{windres} can not write a COFF file to standard output. Note,
2579 for compatability with @command{rc} the option @option{-fo} is also
2580 accepted, but its use is not recommended.
2582 @item -J @var{format}
2583 @itemx --input-format @var{format}
2584 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
2585 @samp{coff}. If no input format is specified, @command{windres} will
2586 guess, as described above.
2588 @item -O @var{format}
2589 @itemx --output-format @var{format}
2590 The output format to generate. @var{format} may be @samp{res},
2591 @samp{rc}, or @samp{coff}. If no output format is specified,
2592 @command{windres} will guess, as described above.
2594 @item -F @var{target}
2595 @itemx --target @var{target}
2596 Specify the BFD format to use for a COFF file as input or output. This
2597 is a BFD target name; you can use the @option{--help} option to see a list
2598 of supported targets. Normally @command{windres} will use the default
2599 format, which is the first one listed by the @option{--help} option.
2601 @ref{Target Selection}.
2604 @item --preprocessor @var{program}
2605 When @command{windres} reads an @code{rc} file, it runs it through the C
2606 preprocessor first. This option may be used to specify the preprocessor
2607 to use, including any leading arguments. The default preprocessor
2608 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
2610 @item -I @var{directory}
2611 @itemx --include-dir @var{directory}
2612 Specify an include directory to use when reading an @code{rc} file.
2613 @command{windres} will pass this to the preprocessor as an @option{-I}
2614 option. @command{windres} will also search this directory when looking for
2615 files named in the @code{rc} file. If the argument passed to this command
2616 matches any of the supported @var{formats} (as descrived in the @option{-J}
2617 option), it will issue a deprecation warning, and behave just like the
2618 @option{-J} option. New programs should not use this behaviour. If a
2619 directory happens to match a @var{format}, simple prefix it with @samp{./}
2620 to disable the backward compatibility.
2622 @item -D @var{target}
2623 @itemx --define @var{sym}[=@var{val}]
2624 Specify a @option{-D} option to pass to the preprocessor when reading an
2627 @item -U @var{target}
2628 @itemx --undefine @var{sym}
2629 Specify a @option{-U} option to pass to the preprocessor when reading an
2633 Ignored for compatibility with rc.
2636 Enable verbose mode. This tells you what the preprocessor is if you
2640 @item --language @var{val}
2641 Specify the default language to use when reading an @code{rc} file.
2642 @var{val} should be a hexadecimal language code. The low eight bits are
2643 the language, and the high eight bits are the sublanguage.
2645 @item --use-temp-file
2646 Use a temporary file to instead of using popen to read the output of
2647 the preprocessor. Use this option if the popen implementation is buggy
2648 on the host (eg., certain non-English language versions of Windows 95 and
2649 Windows 98 are known to have buggy popen where the output will instead
2652 @item --no-use-temp-file
2653 Use popen, not a temporary file, to read the output of the preprocessor.
2654 This is the default behaviour.
2658 Prints a usage summary.
2662 Prints the version number for @command{windres}.
2665 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
2666 this will turn on parser debugging.
2672 @c man begin SEEALSO windres
2673 the Info entries for @file{binutils}.
2678 @chapter Create files needed to build and use DLLs
2682 @command{dlltool} may be used to create the files needed to build and use
2683 dynamic link libraries (DLLs).
2686 @emph{Warning:} @command{dlltool} is not always built as part of the binary
2687 utilities, since it is only useful for those targets which support DLLs.
2690 @c man title dlltool Create files needed to build and use DLLs.
2693 @c man begin SYNOPSIS dlltool
2694 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
2695 [@option{-b}|@option{--base-file} @var{base-file-name}]
2696 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
2697 [@option{-z}|@option{--output-def} @var{def-file-name}]
2698 [@option{-l}|@option{--output-lib} @var{library-file-name}]
2699 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
2700 [@option{--exclude-symbols} @var{list}]
2701 [@option{--no-default-excludes}]
2702 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
2703 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
2704 [@option{-a}|@option{--add-indirect}] [@option{-U}|@option{--add-underscore}] [@option{-k}|@option{--kill-at}]
2705 [@option{-A}|@option{--add-stdcall-alias}]
2706 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}] [@option{-i}|@option{--interwork}]
2707 [@option{-n}|@option{--nodelete}] [@option{-v}|@option{--verbose}]
2708 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
2709 [object-file @dots{}]
2713 @c man begin DESCRIPTION dlltool
2715 @command{dlltool} reads its inputs, which can come from the @option{-d} and
2716 @option{-b} options as well as object files specified on the command
2717 line. It then processes these inputs and if the @option{-e} option has
2718 been specified it creates a exports file. If the @option{-l} option
2719 has been specified it creates a library file and if the @option{-z} option
2720 has been specified it creates a def file. Any or all of the @option{-e},
2721 @option{-l} and @option{-z} options can be present in one invocation of
2724 When creating a DLL, along with the source for the DLL, it is necessary
2725 to have three other files. @command{dlltool} can help with the creation of
2728 The first file is a @samp{.def} file which specifies which functions are
2729 exported from the DLL, which functions the DLL imports, and so on. This
2730 is a text file and can be created by hand, or @command{dlltool} can be used
2731 to create it using the @option{-z} option. In this case @command{dlltool}
2732 will scan the object files specified on its command line looking for
2733 those functions which have been specially marked as being exported and
2734 put entries for them in the .def file it creates.
2736 In order to mark a function as being exported from a DLL, it needs to
2737 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
2738 section of the object file. This can be done in C by using the
2742 asm (".section .drectve");
2743 asm (".ascii \"-export:my_func\"");
2745 int my_func (void) @{ @dots{} @}
2748 The second file needed for DLL creation is an exports file. This file
2749 is linked with the object files that make up the body of the DLL and it
2750 handles the interface between the DLL and the outside world. This is a
2751 binary file and it can be created by giving the @option{-e} option to
2752 @command{dlltool} when it is creating or reading in a .def file.
2754 The third file needed for DLL creation is the library file that programs
2755 will link with in order to access the functions in the DLL. This file
2756 can be created by giving the @option{-l} option to dlltool when it
2757 is creating or reading in a .def file.
2759 @command{dlltool} builds the library file by hand, but it builds the
2760 exports file by creating temporary files containing assembler statements
2761 and then assembling these. The @option{-S} command line option can be
2762 used to specify the path to the assembler that dlltool will use,
2763 and the @option{-f} option can be used to pass specific flags to that
2764 assembler. The @option{-n} can be used to prevent dlltool from deleting
2765 these temporary assembler files when it is done, and if @option{-n} is
2766 specified twice then this will prevent dlltool from deleting the
2767 temporary object files it used to build the library.
2769 Here is an example of creating a DLL from a source file @samp{dll.c} and
2770 also creating a program (from an object file called @samp{program.o})
2775 dlltool -e exports.o -l dll.lib dll.o
2776 gcc dll.o exports.o -o dll.dll
2777 gcc program.o dll.lib -o program
2782 @c man begin OPTIONS dlltool
2784 The command line options have the following meanings:
2788 @item -d @var{filename}
2789 @itemx --input-def @var{filename}
2790 @cindex input .def file
2791 Specifies the name of a .def file to be read in and processed.
2793 @item -b @var{filename}
2794 @itemx --base-file @var{filename}
2796 Specifies the name of a base file to be read in and processed. The
2797 contents of this file will be added to the relocation section in the
2798 exports file generated by dlltool.
2800 @item -e @var{filename}
2801 @itemx --output-exp @var{filename}
2802 Specifies the name of the export file to be created by dlltool.
2804 @item -z @var{filename}
2805 @itemx --output-def @var{filename}
2806 Specifies the name of the .def file to be created by dlltool.
2808 @item -l @var{filename}
2809 @itemx --output-lib @var{filename}
2810 Specifies the name of the library file to be created by dlltool.
2812 @item --export-all-symbols
2813 Treat all global and weak defined symbols found in the input object
2814 files as symbols to be exported. There is a small list of symbols which
2815 are not exported by default; see the @option{--no-default-excludes}
2816 option. You may add to the list of symbols to not export by using the
2817 @option{--exclude-symbols} option.
2819 @item --no-export-all-symbols
2820 Only export symbols explicitly listed in an input .def file or in
2821 @samp{.drectve} sections in the input object files. This is the default
2822 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
2823 attributes in the source code.
2825 @item --exclude-symbols @var{list}
2826 Do not export the symbols in @var{list}. This is a list of symbol names
2827 separated by comma or colon characters. The symbol names should not
2828 contain a leading underscore. This is only meaningful when
2829 @option{--export-all-symbols} is used.
2831 @item --no-default-excludes
2832 When @option{--export-all-symbols} is used, it will by default avoid
2833 exporting certain special symbols. The current list of symbols to avoid
2834 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
2835 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
2836 to go ahead and export these special symbols. This is only meaningful
2837 when @option{--export-all-symbols} is used.
2840 @itemx --as @var{path}
2841 Specifies the path, including the filename, of the assembler to be used
2842 to create the exports file.
2844 @item -f @var{options}
2845 @itemx --as-flags @var{options}
2846 Specifies any specific command line options to be passed to the
2847 assembler when building the exports file. This option will work even if
2848 the @option{-S} option is not used. This option only takes one argument,
2849 and if it occurs more than once on the command line, then later
2850 occurrences will override earlier occurrences. So if it is necessary to
2851 pass multiple options to the assembler they should be enclosed in
2855 @itemx --dll-name @var{name}
2856 Specifies the name to be stored in the .def file as the name of the DLL
2857 when the @option{-e} option is used. If this option is not present, then
2858 the filename given to the @option{-e} option will be used as the name of
2861 @item -m @var{machine}
2862 @itemx -machine @var{machine}
2863 Specifies the type of machine for which the library file should be
2864 built. @command{dlltool} has a built in default type, depending upon how
2865 it was created, but this option can be used to override that. This is
2866 normally only useful when creating DLLs for an ARM processor, when the
2867 contents of the DLL are actually encode using Thumb instructions.
2870 @itemx --add-indirect
2871 Specifies that when @command{dlltool} is creating the exports file it
2872 should add a section which allows the exported functions to be
2873 referenced without using the import library. Whatever the hell that
2877 @itemx --add-underscore
2878 Specifies that when @command{dlltool} is creating the exports file it
2879 should prepend an underscore to the names of the exported functions.
2883 Specifies that when @command{dlltool} is creating the exports file it
2884 should not append the string @samp{@@ <number>}. These numbers are
2885 called ordinal numbers and they represent another way of accessing the
2886 function in a DLL, other than by name.
2889 @itemx --add-stdcall-alias
2890 Specifies that when @command{dlltool} is creating the exports file it
2891 should add aliases for stdcall symbols without @samp{@@ <number>}
2892 in addition to the symbols with @samp{@@ <number>}.
2896 Specifies that when @command{dlltool} is creating the exports and library
2897 files it should omit the @code{.idata4} section. This is for compatibility
2898 with certain operating systems.
2902 Specifies that when @command{dlltool} is creating the exports and library
2903 files it should omit the @code{.idata5} section. This is for compatibility
2904 with certain operating systems.
2908 Specifies that @command{dlltool} should mark the objects in the library
2909 file and exports file that it produces as supporting interworking
2910 between ARM and Thumb code.
2914 Makes @command{dlltool} preserve the temporary assembler files it used to
2915 create the exports file. If this option is repeated then dlltool will
2916 also preserve the temporary object files it uses to create the library
2921 Make dlltool describe what it is doing.
2925 Displays a list of command line options and then exits.
2929 Displays dlltool's version number and then exits.
2936 @c man begin SEEALSO dlltool
2937 the Info entries for @file{binutils}.
2944 @cindex ELF file information
2947 @c man title readelf Displays information about ELF files.
2950 @c man begin SYNOPSIS readelf
2951 readelf [@option{-a}|@option{--all}]
2952 [@option{-h}|@option{--file-header}]
2953 [@option{-l}|@option{--program-headers}|@option{--segments}]
2954 [@option{-S}|@option{--section-headers}|@option{--sections}]
2955 [@option{-e}|@option{--headers}]
2956 [@option{-s}|@option{--syms}|@option{--symbols}]
2957 [@option{-n}|@option{--notes}]
2958 [@option{-r}|@option{--relocs}]
2959 [@option{-u}|@option{--unwind}]
2960 [@option{-d}|@option{--dynamic}]
2961 [@option{-V}|@option{--version-info}]
2962 [@option{-A}|@option{--arch-specific}]
2963 [@option{-D}|@option{--use-dynamic}]
2964 [@option{-x} <number>|@option{--hex-dump=}<number>]
2965 [@option{-w[liaprmfFso]}|
2966 @option{--debug-dump}[=line,=info,=abbrev,=pubnames,=ranges,=macro,=frames,=frames-interp,=str,=loc]]
2967 [@option{-I}|@option{-histogram}]
2968 [@option{-v}|@option{--version}]
2969 [@option{-W}|@option{--wide}]
2970 [@option{-H}|@option{--help}]
2971 @var{elffile}@dots{}
2975 @c man begin DESCRIPTION readelf
2977 @command{readelf} displays information about one or more ELF format object
2978 files. The options control what particular information to display.
2980 @var{elffile}@dots{} are the object files to be examined. At the
2981 moment, @command{readelf} does not support examining archives, nor does it
2982 support examining 64 bit ELF files.
2986 @c man begin OPTIONS readelf
2988 The long and short forms of options, shown here as alternatives, are
2989 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
2995 Equivalent to specifiying @option{--file-header},
2996 @option{--program-headers}, @option{--sections}, @option{--symbols},
2997 @option{--relocs}, @option{--dynamic}, @option{--notes} and
2998 @option{--version-info}.
3001 @itemx --file-header
3002 @cindex ELF file header information
3003 Displays the information contained in the ELF header at the start of the
3007 @itemx --program-headers
3009 @cindex ELF program header information
3010 @cindex ELF segment information
3011 Displays the information contained in the file's segment headers, if it
3016 @itemx --section-headers
3017 @cindex ELF section information
3018 Displays the information contained in the file's section headers, if it
3024 @cindex ELF symbol table information
3025 Displays the entries in symbol table section of the file, if it has one.
3029 Display all the headers in the file. Equivalent to @option{-h -l -S}.
3033 @cindex ELF core notes
3034 Displays the contents of the NOTE segment, if it exists.
3038 @cindex ELF reloc information
3039 Displays the contents of the file's relocation section, if it has one.
3043 @cindex unwind information
3044 Displays the contents of the file's unwind section, if it has one. Only
3045 the unwind sections for IA64 ELF files are currently supported.
3049 @cindex unwind information
3050 Displays the contents of the file's unwind section, if it has one. Only
3051 the unwind sections for IA64 ELF files are currently supported.
3055 @cindex ELF dynamic section information
3056 Displays the contents of the file's dynamic section, if it has one.
3059 @itemx --version-info
3060 @cindex ELF version sections informations
3061 Displays the contents of the version sections in the file, it they
3065 @itemx --arch-specific
3066 Displays architecture-specific information in the file, if there
3070 @itemx --use-dynamic
3071 When displaying symbols, this option makes @command{readelf} use the
3072 symbol table in the file's dynamic section, rather than the one in the
3076 @itemx --hex-dump=<number>
3077 Displays the contents of the indicated section as a hexadecimal dump.
3079 @item -w[liaprmfFso]
3080 @itemx --debug-dump[=line,=info,=abbrev,=pubnames,=ranges,=macro,=frames,=frames-interp,=str,=loc]
3081 Displays the contents of the debug sections in the file, if any are
3082 present. If one of the optional letters or words follows the switch
3083 then only data found in those specific sections will be dumped.
3087 Display a histogram of bucket list lengths when displaying the contents
3088 of the symbol tables.
3092 Display the version number of readelf.
3096 Don't break output lines to fit into 80 columns. By default
3097 @command{readelf} breaks section header and segment listing lines for
3098 64-bit ELF files, so that they fit into 80 columns. This option causes
3099 @command{readelf} to print each section header resp. each segment one a
3100 single line, which is far more readable on terminals wider than 80 columns.
3104 Display the command line options understood by @command{readelf}.
3111 @c man begin SEEALSO readelf
3112 objdump(1), and the Info entries for @file{binutils}.
3116 @node Selecting The Target System
3117 @chapter Selecting the Target System
3119 You can specify two aspects of the target system to the @sc{gnu}
3120 binary file utilities, each in several ways:
3130 In the following summaries, the lists of ways to specify values are in
3131 order of decreasing precedence. The ways listed first override those
3134 The commands to list valid values only list the values for which the
3135 programs you are running were configured. If they were configured with
3136 @option{--enable-targets=all}, the commands list most of the available
3137 values, but a few are left out; not all targets can be configured in at
3138 once because some of them can only be configured @dfn{native} (on hosts
3139 with the same type as the target system).
3142 * Target Selection::
3143 * Architecture Selection::
3146 @node Target Selection
3147 @section Target Selection
3149 A @dfn{target} is an object file format. A given target may be
3150 supported for multiple architectures (@pxref{Architecture Selection}).
3151 A target selection may also have variations for different operating
3152 systems or architectures.
3154 The command to list valid target values is @samp{objdump -i}
3155 (the first column of output contains the relevant information).
3157 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
3158 @samp{a.out-sunos-big}.
3160 You can also specify a target using a configuration triplet. This is
3161 the same sort of name that is passed to @file{configure} to specify a
3162 target. When you use a configuration triplet as an argument, it must be
3163 fully canonicalized. You can see the canonical version of a triplet by
3164 running the shell script @file{config.sub} which is included with the
3167 Some sample configuration triplets are: @samp{m68k-hp-bsd},
3168 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
3170 @subheading @command{objdump} Target
3176 command line option: @option{-b} or @option{--target}
3179 environment variable @code{GNUTARGET}
3182 deduced from the input file
3185 @subheading @command{objcopy} and @command{strip} Input Target
3191 command line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
3194 environment variable @code{GNUTARGET}
3197 deduced from the input file
3200 @subheading @command{objcopy} and @command{strip} Output Target
3206 command line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
3209 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
3212 environment variable @code{GNUTARGET}
3215 deduced from the input file
3218 @subheading @command{nm}, @command{size}, and @command{strings} Target
3224 command line option: @option{--target}
3227 environment variable @code{GNUTARGET}
3230 deduced from the input file
3233 @node Architecture Selection
3234 @section Architecture Selection
3236 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
3237 to run. Its name may contain a colon, separating the name of the
3238 processor family from the name of the particular @sc{cpu}.
3240 The command to list valid architecture values is @samp{objdump -i} (the
3241 second column contains the relevant information).
3243 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
3245 @subheading @command{objdump} Architecture
3251 command line option: @option{-m} or @option{--architecture}
3254 deduced from the input file
3257 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
3263 deduced from the input file
3266 @node Reporting Bugs
3267 @chapter Reporting Bugs
3269 @cindex reporting bugs
3271 Your bug reports play an essential role in making the binary utilities
3274 Reporting a bug may help you by bringing a solution to your problem, or
3275 it may not. But in any case the principal function of a bug report is
3276 to help the entire community by making the next version of the binary
3277 utilities work better. Bug reports are your contribution to their
3280 In order for a bug report to serve its purpose, you must include the
3281 information that enables us to fix the bug.
3284 * Bug Criteria:: Have you found a bug?
3285 * Bug Reporting:: How to report bugs
3289 @section Have You Found a Bug?
3290 @cindex bug criteria
3292 If you are not sure whether you have found a bug, here are some guidelines:
3295 @cindex fatal signal
3298 If a binary utility gets a fatal signal, for any input whatever, that is
3299 a bug. Reliable utilities never crash.
3301 @cindex error on valid input
3303 If a binary utility produces an error message for valid input, that is a
3307 If you are an experienced user of binary utilities, your suggestions for
3308 improvement are welcome in any case.
3312 @section How to Report Bugs
3314 @cindex bugs, reporting
3316 A number of companies and individuals offer support for @sc{gnu}
3317 products. If you obtained the binary utilities from a support
3318 organization, we recommend you contact that organization first.
3320 You can find contact information for many support companies and
3321 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
3324 In any event, we also recommend that you send bug reports for the binary
3325 utilities to @samp{bug-binutils@@gnu.org}.
3327 The fundamental principle of reporting bugs usefully is this:
3328 @strong{report all the facts}. If you are not sure whether to state a
3329 fact or leave it out, state it!
3331 Often people omit facts because they think they know what causes the
3332 problem and assume that some details do not matter. Thus, you might
3333 assume that the name of a file you use in an example does not matter.
3334 Well, probably it does not, but one cannot be sure. Perhaps the bug is
3335 a stray memory reference which happens to fetch from the location where
3336 that pathname is stored in memory; perhaps, if the pathname were
3337 different, the contents of that location would fool the utility into
3338 doing the right thing despite the bug. Play it safe and give a
3339 specific, complete example. That is the easiest thing for you to do,
3340 and the most helpful.
3342 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
3343 it is new to us. Therefore, always write your bug reports on the assumption
3344 that the bug has not been reported previously.
3346 Sometimes people give a few sketchy facts and ask, ``Does this ring a
3347 bell?'' This cannot help us fix a bug, so it is basically useless. We
3348 respond by asking for enough details to enable us to investigate.
3349 You might as well expedite matters by sending them to begin with.
3351 To enable us to fix the bug, you should include all these things:
3355 The version of the utility. Each utility announces it if you start it
3356 with the @option{--version} argument.
3358 Without this, we will not know whether there is any point in looking for
3359 the bug in the current version of the binary utilities.
3362 Any patches you may have applied to the source, including any patches
3363 made to the @code{BFD} library.
3366 The type of machine you are using, and the operating system name and
3370 What compiler (and its version) was used to compile the utilities---e.g.
3374 The command arguments you gave the utility to observe the bug. To
3375 guarantee you will not omit something important, list them all. A copy
3376 of the Makefile (or the output from make) is sufficient.
3378 If we were to try to guess the arguments, we would probably guess wrong
3379 and then we might not encounter the bug.
3382 A complete input file, or set of input files, that will reproduce the
3383 bug. If the utility is reading an object file or files, then it is
3384 generally most helpful to send the actual object files, uuencoded if
3385 necessary to get them through the mail system. Note that
3386 @samp{bug-binutils@@gnu.org} is a mailing list, so you should avoid
3387 sending very large files to it. Making the files available for
3388 anonymous FTP is OK.
3390 If the source files were produced exclusively using @sc{gnu} programs
3391 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
3392 may be OK to send the source files rather than the object files. In
3393 this case, be sure to say exactly what version of @command{gcc}, or
3394 whatever, was used to produce the object files. Also say how
3395 @command{gcc}, or whatever, was configured.
3398 A description of what behavior you observe that you believe is
3399 incorrect. For example, ``It gets a fatal signal.''
3401 Of course, if the bug is that the utility gets a fatal signal, then we
3402 will certainly notice it. But if the bug is incorrect output, we might
3403 not notice unless it is glaringly wrong. You might as well not give us
3404 a chance to make a mistake.
3406 Even if the problem you experience is a fatal signal, you should still
3407 say so explicitly. Suppose something strange is going on, such as your
3408 copy of the utility is out of synch, or you have encountered a bug in
3409 the C library on your system. (This has happened!) Your copy might
3410 crash and ours would not. If you told us to expect a crash, then when
3411 ours fails to crash, we would know that the bug was not happening for
3412 us. If you had not told us to expect a crash, then we would not be able
3413 to draw any conclusion from our observations.
3416 If you wish to suggest changes to the source, send us context diffs, as
3417 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
3418 option. Always send diffs from the old file to the new file. If you
3419 wish to discuss something in the @command{ld} source, refer to it by
3420 context, not by line number.
3422 The line numbers in our development sources will not match those in your
3423 sources. Your line numbers would convey no useful information to us.
3426 Here are some things that are not necessary:
3430 A description of the envelope of the bug.
3432 Often people who encounter a bug spend a lot of time investigating
3433 which changes to the input file will make the bug go away and which
3434 changes will not affect it.
3436 This is often time consuming and not very useful, because the way we
3437 will find the bug is by running a single example under the debugger
3438 with breakpoints, not by pure deduction from a series of examples.
3439 We recommend that you save your time for something else.
3441 Of course, if you can find a simpler example to report @emph{instead}
3442 of the original one, that is a convenience for us. Errors in the
3443 output will be easier to spot, running under the debugger will take
3444 less time, and so on.
3446 However, simplification is not vital; if you do not want to do this,
3447 report the bug anyway and send us the entire test case you used.
3450 A patch for the bug.
3452 A patch for the bug does help us if it is a good one. But do not omit
3453 the necessary information, such as the test case, on the assumption that
3454 a patch is all we need. We might see problems with your patch and decide
3455 to fix the problem another way, or we might not understand it at all.
3457 Sometimes with programs as complicated as the binary utilities it is
3458 very hard to construct an example that will make the program follow a
3459 certain path through the code. If you do not send us the example, we
3460 will not be able to construct one, so we will not be able to verify that
3463 And if we cannot understand what bug you are trying to fix, or why your
3464 patch should be an improvement, we will not install it. A test case will
3465 help us to understand.
3468 A guess about what the bug is or what it depends on.
3470 Such guesses are usually wrong. Even we cannot guess right about such
3471 things without first using the debugger to find the facts.