1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @c Copyright 2001, 2002, 2003, 2004, 2005 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, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
33 2000, 2001, 2002, 2003, 2004, 2005 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, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
58 @c 2000, 2001, 2002, 2003, 2004, 2005 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}
71 @subtitle @value{UPDATED}
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, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
84 2000, 2001, 2002, 2003, 2004, 2005 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}][@option{--special-syms}]
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 symbol is determined in a system-specific manner without
752 error. On some systems, uppercase indicates that a default value has been
757 The symbol is a stabs symbol in an a.out object file. In this case, the
758 next values printed are the stabs other field, the stabs desc field, and
759 the stab type. Stabs symbols are used to hold debugging information.
761 For more information, see @ref{Top,Stabs,Stabs Overview,stabs.info, The
762 ``stabs'' debug format}.
766 The symbol type is unknown, or object file format specific.
775 @c man begin OPTIONS nm
776 The long and short forms of options, shown here as alternatives, are
782 @itemx --print-file-name
783 @cindex input file name
785 @cindex source file name
786 Precede each symbol by the name of the input file (or archive member)
787 in which it was found, rather than identifying the input file once only,
788 before all of its symbols.
792 @cindex debugging symbols
793 Display all symbols, even debugger-only symbols; normally these are not
797 @cindex @command{nm} format
798 @cindex @command{nm} compatibility
799 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
802 @itemx --demangle[=@var{style}]
803 @cindex demangling in nm
804 Decode (@dfn{demangle}) low-level symbol names into user-level names.
805 Besides removing any initial underscore prepended by the system, this
806 makes C++ function names readable. Different compilers have different
807 mangling styles. The optional demangling style argument can be used to
808 choose an appropriate demangling style for your compiler. @xref{c++filt},
809 for more information on demangling.
812 Do not demangle low-level symbol names. This is the default.
816 @cindex dynamic symbols
817 Display the dynamic symbols rather than the normal symbols. This is
818 only meaningful for dynamic objects, such as certain types of shared
821 @item -f @var{format}
822 @itemx --format=@var{format}
823 @cindex @command{nm} format
824 @cindex @command{nm} compatibility
825 Use the output format @var{format}, which can be @code{bsd},
826 @code{sysv}, or @code{posix}. The default is @code{bsd}.
827 Only the first character of @var{format} is significant; it can be
828 either upper or lower case.
832 @cindex external symbols
833 Display only external symbols.
836 @itemx --line-numbers
837 @cindex symbol line numbers
838 For each symbol, use debugging information to try to find a filename and
839 line number. For a defined symbol, look for the line number of the
840 address of the symbol. For an undefined symbol, look for the line
841 number of a relocation entry which refers to the symbol. If line number
842 information can be found, print it after the other symbol information.
846 @itemx --numeric-sort
847 Sort symbols numerically by their addresses, rather than alphabetically
852 @cindex sorting symbols
853 Do not bother to sort the symbols in any order; print them in the order
858 Use the POSIX.2 standard output format instead of the default format.
859 Equivalent to @samp{-f posix}.
863 Print size, not the value, of defined symbols for the @code{bsd} output format.
867 @cindex symbol index, listing
868 When listing symbols from archive members, include the index: a mapping
869 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
870 contain definitions for which names.
873 @itemx --reverse-sort
874 Reverse the order of the sort (whether numeric or alphabetic); let the
878 Sort symbols by size. The size is computed as the difference between
879 the value of the symbol and the value of the symbol with the next higher
880 value. If the @code{bsd} output format is used the size of the symbol
881 is printed, rather than the value, and @samp{-S} must be used in order
882 both size and value to be printed.
885 Display symbols which have a target-specific special meaning. These
886 symbols are usually used by the target for some special processing and
887 are not normally helpful when included included in the normal symbol
888 lists. For example for ARM targets this option would skip the mapping
889 symbols used to mark transistions between ARM code, THUMB code and
893 @itemx --radix=@var{radix}
894 Use @var{radix} as the radix for printing the symbol values. It must be
895 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
897 @item --target=@var{bfdname}
898 @cindex object code format
899 Specify an object code format other than your system's default format.
900 @xref{Target Selection}, for more information.
903 @itemx --undefined-only
904 @cindex external symbols
905 @cindex undefined symbols
906 Display only undefined symbols (those external to each object file).
909 @cindex external symbols
910 @cindex undefined symbols
911 Display only defined symbols for each object file.
915 Show the version number of @command{nm} and exit.
918 This option is ignored for compatibility with the AIX version of
919 @command{nm}. It takes one parameter which must be the string
920 @option{32_64}. The default mode of AIX @command{nm} corresponds
921 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
924 Show a summary of the options to @command{nm} and exit.
930 @c man begin SEEALSO nm
931 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
938 @c man title objcopy copy and translate object files
941 @c man begin SYNOPSIS objcopy
942 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
943 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
944 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
945 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
946 [@option{-S}|@option{--strip-all}]
947 [@option{-g}|@option{--strip-debug}]
948 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
949 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
950 [@option{--strip-unneeded-symbol=}@var{symbolname}]
951 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
952 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
953 [@option{--globalize-symbol=}@var{symbolname}]
954 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
955 [@option{-w}|@option{--wildcard}]
956 [@option{-x}|@option{--discard-all}]
957 [@option{-X}|@option{--discard-locals}]
958 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
959 [@option{-i} @var{interleave}|@option{--interleave=}@var{interleave}]
960 [@option{-j} @var{sectionname}|@option{--only-section=}@var{sectionname}]
961 [@option{-R} @var{sectionname}|@option{--remove-section=}@var{sectionname}]
962 [@option{-p}|@option{--preserve-dates}]
963 [@option{--debugging}]
964 [@option{--gap-fill=}@var{val}]
965 [@option{--pad-to=}@var{address}]
966 [@option{--set-start=}@var{val}]
967 [@option{--adjust-start=}@var{incr}]
968 [@option{--change-addresses=}@var{incr}]
969 [@option{--change-section-address} @var{section}@{=,+,-@}@var{val}]
970 [@option{--change-section-lma} @var{section}@{=,+,-@}@var{val}]
971 [@option{--change-section-vma} @var{section}@{=,+,-@}@var{val}]
972 [@option{--change-warnings}] [@option{--no-change-warnings}]
973 [@option{--set-section-flags} @var{section}=@var{flags}]
974 [@option{--add-section} @var{sectionname}=@var{filename}]
975 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
976 [@option{--change-leading-char}] [@option{--remove-leading-char}]
977 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
978 [@option{--redefine-sym} @var{old}=@var{new}]
979 [@option{--redefine-syms=}@var{filename}]
981 [@option{--keep-symbols=}@var{filename}]
982 [@option{--strip-symbols=}@var{filename}]
983 [@option{--strip-unneeded-symbols=}@var{filename}]
984 [@option{--keep-global-symbols=}@var{filename}]
985 [@option{--localize-symbols=}@var{filename}]
986 [@option{--globalize-symbols=}@var{filename}]
987 [@option{--weaken-symbols=}@var{filename}]
988 [@option{--alt-machine-code=}@var{index}]
989 [@option{--prefix-symbols=}@var{string}]
990 [@option{--prefix-sections=}@var{string}]
991 [@option{--prefix-alloc-sections=}@var{string}]
992 [@option{--add-gnu-debuglink=}@var{path-to-file}]
993 [@option{--only-keep-debug}]
994 [@option{--writable-text}]
995 [@option{--readonly-text}]
998 [@option{-v}|@option{--verbose}]
999 [@option{-V}|@option{--version}]
1000 [@option{--help}] [@option{--info}]
1001 @var{infile} [@var{outfile}]
1005 @c man begin DESCRIPTION objcopy
1006 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1007 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1008 read and write the object files. It can write the destination object
1009 file in a format different from that of the source object file. The
1010 exact behavior of @command{objcopy} is controlled by command-line options.
1011 Note that @command{objcopy} should be able to copy a fully linked file
1012 between any two formats. However, copying a relocatable object file
1013 between any two formats may not work as expected.
1015 @command{objcopy} creates temporary files to do its translations and
1016 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1017 translation work; it has access to all the formats described in @sc{bfd}
1018 and thus is able to recognize most formats without being told
1019 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1021 @command{objcopy} can be used to generate S-records by using an output
1022 target of @samp{srec} (e.g., use @samp{-O srec}).
1024 @command{objcopy} can be used to generate a raw binary file by using an
1025 output target of @samp{binary} (e.g., use @option{-O binary}). When
1026 @command{objcopy} generates a raw binary file, it will essentially produce
1027 a memory dump of the contents of the input object file. All symbols and
1028 relocation information will be discarded. The memory dump will start at
1029 the load address of the lowest section copied into the output file.
1031 When generating an S-record or a raw binary file, it may be helpful to
1032 use @option{-S} to remove sections containing debugging information. In
1033 some cases @option{-R} will be useful to remove sections which contain
1034 information that is not needed by the binary file.
1036 Note---@command{objcopy} is not able to change the endianness of its input
1037 files. If the input format has an endianness (some formats do not),
1038 @command{objcopy} can only copy the inputs into file formats that have the
1039 same endianness or which have no endianness (e.g., @samp{srec}).
1043 @c man begin OPTIONS objcopy
1047 @itemx @var{outfile}
1048 The input and output files, respectively.
1049 If you do not specify @var{outfile}, @command{objcopy} creates a
1050 temporary file and destructively renames the result with
1051 the name of @var{infile}.
1053 @item -I @var{bfdname}
1054 @itemx --input-target=@var{bfdname}
1055 Consider the source file's object format to be @var{bfdname}, rather than
1056 attempting to deduce it. @xref{Target Selection}, for more information.
1058 @item -O @var{bfdname}
1059 @itemx --output-target=@var{bfdname}
1060 Write the output file using the object format @var{bfdname}.
1061 @xref{Target Selection}, for more information.
1063 @item -F @var{bfdname}
1064 @itemx --target=@var{bfdname}
1065 Use @var{bfdname} as the object format for both the input and the output
1066 file; i.e., simply transfer data from source to destination with no
1067 translation. @xref{Target Selection}, for more information.
1069 @item -B @var{bfdarch}
1070 @itemx --binary-architecture=@var{bfdarch}
1071 Useful when transforming a raw binary input file into an object file.
1072 In this case the output architecture can be set to @var{bfdarch}. This
1073 option will be ignored if the input file has a known @var{bfdarch}. You
1074 can access this binary data inside a program by referencing the special
1075 symbols that are created by the conversion process. These symbols are
1076 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1077 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1078 an object file and then access it in your code using these symbols.
1080 @item -j @var{sectionname}
1081 @itemx --only-section=@var{sectionname}
1082 Copy only the named section from the input file to the output file.
1083 This option may be given more than once. Note that using this option
1084 inappropriately may make the output file unusable.
1086 @item -R @var{sectionname}
1087 @itemx --remove-section=@var{sectionname}
1088 Remove any section named @var{sectionname} from the output file. This
1089 option may be given more than once. Note that using this option
1090 inappropriately may make the output file unusable.
1094 Do not copy relocation and symbol information from the source file.
1097 @itemx --strip-debug
1098 Do not copy debugging symbols or sections from the source file.
1100 @item --strip-unneeded
1101 Strip all symbols that are not needed for relocation processing.
1103 @item -K @var{symbolname}
1104 @itemx --keep-symbol=@var{symbolname}
1105 When stripping symbols, keep symbol @var{symbolname} even if it would
1106 normally be stripped. This option may be given more than once.
1108 @item -N @var{symbolname}
1109 @itemx --strip-symbol=@var{symbolname}
1110 Do not copy symbol @var{symbolname} from the source file. This option
1111 may be given more than once.
1113 @item --strip-unneeded-symbol=@var{symbolname}
1114 Do not copy symbol @var{symbolname} from the source file unless it is needed
1115 by a relocation. This option may be given more than once.
1117 @item -G @var{symbolname}
1118 @itemx --keep-global-symbol=@var{symbolname}
1119 Keep only symbol @var{symbolname} global. Make all other symbols local
1120 to the file, so that they are not visible externally. This option may
1121 be given more than once.
1123 @item -L @var{symbolname}
1124 @itemx --localize-symbol=@var{symbolname}
1125 Make symbol @var{symbolname} local to the file, so that it is not
1126 visible externally. This option may be given more than once.
1128 @item -W @var{symbolname}
1129 @itemx --weaken-symbol=@var{symbolname}
1130 Make symbol @var{symbolname} weak. This option may be given more than once.
1132 @item --globalize-symbol=@var{symbolname}
1133 Give symbol @var{symbolname} global scoping so that it is visible
1134 outside of the file in which it is defined. This option may be given
1139 Permit regular expressions in @var{symbolname}s used in other command
1140 line options. The question mark (?), asterisk (*), backslash (\) and
1141 square brackets ([]) operators can be used anywhere in the symbol
1142 name. If the first character of the symbol name is the exclamation
1143 point (!) then the sense of the switch is reversed for that symbol.
1150 would cause objcopy to weaken all symbols that start with ``fo''
1151 except for the symbol ``foo''.
1154 @itemx --discard-all
1155 Do not copy non-global symbols from the source file.
1156 @c FIXME any reason to prefer "non-global" to "local" here?
1159 @itemx --discard-locals
1160 Do not copy compiler-generated local symbols.
1161 (These usually start with @samp{L} or @samp{.}.)
1164 @itemx --byte=@var{byte}
1165 Keep only every @var{byte}th byte of the input file (header data is not
1166 affected). @var{byte} can be in the range from 0 to @var{interleave}-1,
1167 where @var{interleave} is given by the @option{-i} or @option{--interleave}
1168 option, or the default of 4. This option is useful for creating files
1169 to program @sc{rom}. It is typically used with an @code{srec} output
1172 @item -i @var{interleave}
1173 @itemx --interleave=@var{interleave}
1174 Only copy one out of every @var{interleave} bytes. Select which byte to
1175 copy with the @option{-b} or @option{--byte} option. The default is 4.
1176 @command{objcopy} ignores this option if you do not specify either @option{-b} or
1180 @itemx --preserve-dates
1181 Set the access and modification dates of the output file to be the same
1182 as those of the input file.
1185 Convert debugging information, if possible. This is not the default
1186 because only certain debugging formats are supported, and the
1187 conversion process can be time consuming.
1189 @item --gap-fill @var{val}
1190 Fill gaps between sections with @var{val}. This operation applies to
1191 the @emph{load address} (LMA) of the sections. It is done by increasing
1192 the size of the section with the lower address, and filling in the extra
1193 space created with @var{val}.
1195 @item --pad-to @var{address}
1196 Pad the output file up to the load address @var{address}. This is
1197 done by increasing the size of the last section. The extra space is
1198 filled in with the value specified by @option{--gap-fill} (default zero).
1200 @item --set-start @var{val}
1201 Set the start address of the new file to @var{val}. Not all object file
1202 formats support setting the start address.
1204 @item --change-start @var{incr}
1205 @itemx --adjust-start @var{incr}
1206 @cindex changing start address
1207 Change the start address by adding @var{incr}. Not all object file
1208 formats support setting the start address.
1210 @item --change-addresses @var{incr}
1211 @itemx --adjust-vma @var{incr}
1212 @cindex changing object addresses
1213 Change the VMA and LMA addresses of all sections, as well as the start
1214 address, by adding @var{incr}. Some object file formats do not permit
1215 section addresses to be changed arbitrarily. Note that this does not
1216 relocate the sections; if the program expects sections to be loaded at a
1217 certain address, and this option is used to change the sections such
1218 that they are loaded at a different address, the program may fail.
1220 @item --change-section-address @var{section}@{=,+,-@}@var{val}
1221 @itemx --adjust-section-vma @var{section}@{=,+,-@}@var{val}
1222 @cindex changing section address
1223 Set or change both the VMA address and the LMA address of the named
1224 @var{section}. If @samp{=} is used, the section address is set to
1225 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1226 section address. See the comments under @option{--change-addresses},
1227 above. If @var{section} does not exist in the input file, a warning will
1228 be issued, unless @option{--no-change-warnings} is used.
1230 @item --change-section-lma @var{section}@{=,+,-@}@var{val}
1231 @cindex changing section LMA
1232 Set or change the LMA address of the named @var{section}. The LMA
1233 address is the address where the section will be loaded into memory at
1234 program load time. Normally this is the same as the VMA address, which
1235 is the address of the section at program run time, but on some systems,
1236 especially those where a program is held in ROM, the two can be
1237 different. If @samp{=} is used, the section address is set to
1238 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1239 section address. See the comments under @option{--change-addresses},
1240 above. If @var{section} does not exist in the input file, a warning
1241 will be issued, unless @option{--no-change-warnings} is used.
1243 @item --change-section-vma @var{section}@{=,+,-@}@var{val}
1244 @cindex changing section VMA
1245 Set or change the VMA address of the named @var{section}. The VMA
1246 address is the address where the section will be located once the
1247 program has started executing. Normally this is the same as the LMA
1248 address, which is the address where the section will be loaded into
1249 memory, but on some systems, especially those where a program is held in
1250 ROM, the two can be different. If @samp{=} is used, the section address
1251 is set to @var{val}. Otherwise, @var{val} is added to or subtracted
1252 from the section address. See the comments under
1253 @option{--change-addresses}, above. If @var{section} does not exist in
1254 the input file, a warning will be issued, unless
1255 @option{--no-change-warnings} is used.
1257 @item --change-warnings
1258 @itemx --adjust-warnings
1259 If @option{--change-section-address} or @option{--change-section-lma} or
1260 @option{--change-section-vma} is used, and the named section does not
1261 exist, issue a warning. This is the default.
1263 @item --no-change-warnings
1264 @itemx --no-adjust-warnings
1265 Do not issue a warning if @option{--change-section-address} or
1266 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1267 if the named section does not exist.
1269 @item --set-section-flags @var{section}=@var{flags}
1270 Set the flags for the named section. The @var{flags} argument is a
1271 comma separated string of flag names. The recognized names are
1272 @samp{alloc}, @samp{contents}, @samp{load}, @samp{noload},
1273 @samp{readonly}, @samp{code}, @samp{data}, @samp{rom}, @samp{share}, and
1274 @samp{debug}. You can set the @samp{contents} flag for a section which
1275 does not have contents, but it is not meaningful to clear the
1276 @samp{contents} flag of a section which does have contents--just remove
1277 the section instead. Not all flags are meaningful for all object file
1280 @item --add-section @var{sectionname}=@var{filename}
1281 Add a new section named @var{sectionname} while copying the file. The
1282 contents of the new section are taken from the file @var{filename}. The
1283 size of the section will be the size of the file. This option only
1284 works on file formats which can support sections with arbitrary names.
1286 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1287 Rename a section from @var{oldname} to @var{newname}, optionally
1288 changing the section's flags to @var{flags} in the process. This has
1289 the advantage over usng a linker script to perform the rename in that
1290 the output stays as an object file and does not become a linked
1293 This option is particularly helpful when the input format is binary,
1294 since this will always create a section called .data. If for example,
1295 you wanted instead to create a section called .rodata containing binary
1296 data you could use the following command line to achieve it:
1299 objcopy -I binary -O <output_format> -B <architecture> \
1300 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1301 <input_binary_file> <output_object_file>
1304 @item --change-leading-char
1305 Some object file formats use special characters at the start of
1306 symbols. The most common such character is underscore, which compilers
1307 often add before every symbol. This option tells @command{objcopy} to
1308 change the leading character of every symbol when it converts between
1309 object file formats. If the object file formats use the same leading
1310 character, this option has no effect. Otherwise, it will add a
1311 character, or remove a character, or change a character, as
1314 @item --remove-leading-char
1315 If the first character of a global symbol is a special symbol leading
1316 character used by the object file format, remove the character. The
1317 most common symbol leading character is underscore. This option will
1318 remove a leading underscore from all global symbols. This can be useful
1319 if you want to link together objects of different file formats with
1320 different conventions for symbol names. This is different from
1321 @option{--change-leading-char} because it always changes the symbol name
1322 when appropriate, regardless of the object file format of the output
1325 @item --srec-len=@var{ival}
1326 Meaningful only for srec output. Set the maximum length of the Srecords
1327 being produced to @var{ival}. This length covers both address, data and
1330 @item --srec-forceS3
1331 Meaningful only for srec output. Avoid generation of S1/S2 records,
1332 creating S3-only record format.
1334 @item --redefine-sym @var{old}=@var{new}
1335 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1336 when one is trying link two things together for which you have no
1337 source, and there are name collisions.
1339 @item --redefine-syms=@var{filename}
1340 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1341 listed in the file @var{filename}. @var{filename} is simply a flat file,
1342 with one symbol pair per line. Line comments may be introduced by the hash
1343 character. This option may be given more than once.
1346 Change all global symbols in the file to be weak. This can be useful
1347 when building an object which will be linked against other objects using
1348 the @option{-R} option to the linker. This option is only effective when
1349 using an object file format which supports weak symbols.
1351 @item --keep-symbols=@var{filename}
1352 Apply @option{--keep-symbol} option to each symbol listed in the file
1353 @var{filename}. @var{filename} is simply a flat file, with one symbol
1354 name per line. Line comments may be introduced by the hash character.
1355 This option may be given more than once.
1357 @item --strip-symbols=@var{filename}
1358 Apply @option{--strip-symbol} option to each symbol listed in the file
1359 @var{filename}. @var{filename} is simply a flat file, with one symbol
1360 name per line. Line comments may be introduced by the hash character.
1361 This option may be given more than once.
1363 @item --strip-unneeded-symbols=@var{filename}
1364 Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1365 the file @var{filename}. @var{filename} is simply a flat file, with one
1366 symbol name per line. Line comments may be introduced by the hash
1367 character. This option may be given more than once.
1369 @item --keep-global-symbols=@var{filename}
1370 Apply @option{--keep-global-symbol} option to each symbol listed in the
1371 file @var{filename}. @var{filename} is simply a flat file, with one
1372 symbol name per line. Line comments may be introduced by the hash
1373 character. This option may be given more than once.
1375 @item --localize-symbols=@var{filename}
1376 Apply @option{--localize-symbol} option to each symbol listed in the file
1377 @var{filename}. @var{filename} is simply a flat file, with one symbol
1378 name per line. Line comments may be introduced by the hash character.
1379 This option may be given more than once.
1381 @item --globalize-symbols=@var{filename}
1382 Apply @option{--globalize-symbol} option to each symbol listed in the file
1383 @var{filename}. @var{filename} is simply a flat file, with one symbol
1384 name per line. Line comments may be introduced by the hash character.
1385 This option may be given more than once.
1387 @item --weaken-symbols=@var{filename}
1388 Apply @option{--weaken-symbol} option to each symbol listed in the file
1389 @var{filename}. @var{filename} is simply a flat file, with one symbol
1390 name per line. Line comments may be introduced by the hash character.
1391 This option may be given more than once.
1393 @item --alt-machine-code=@var{index}
1394 If the output architecture has alternate machine codes, use the
1395 @var{index}th code instead of the default one. This is useful in case
1396 a machine is assigned an official code and the tool-chain adopts the
1397 new code, but other applications still depend on the original code
1400 @item --writable-text
1401 Mark the output text as writable. This option isn't meaningful for all
1402 object file formats.
1404 @item --readonly-text
1405 Make the output text write protected. This option isn't meaningful for all
1406 object file formats.
1409 Mark the output file as demand paged. This option isn't meaningful for all
1410 object file formats.
1413 Mark the output file as impure. This option isn't meaningful for all
1414 object file formats.
1416 @item --prefix-symbols=@var{string}
1417 Prefix all symbols in the output file with @var{string}.
1419 @item --prefix-sections=@var{string}
1420 Prefix all section names in the output file with @var{string}.
1422 @item --prefix-alloc-sections=@var{string}
1423 Prefix all the names of all allocated sections in the output file with
1426 @item --add-gnu-debuglink=@var{path-to-file}
1427 Creates a .gnu_debuglink section which contains a reference to @var{path-to-file}
1428 and adds it to the output file.
1430 @item --only-keep-debug
1431 Strip a file, removing contents of any sections that would not be
1432 stripped by @option{--strip-debug} and leaving the debugging sections
1435 The intention is that this option will be used in conjunction with
1436 @option{--add-gnu-debuglink} to create a two part executable. One a
1437 stripped binary which will occupy less space in RAM and in a
1438 distribution and the second a debugging information file which is only
1439 needed if debugging abilities are required. The suggested procedure
1440 to create these files is as follows:
1443 @item Link the executable as normal. Assuming that is is called
1445 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
1446 create a file containing the debugging info.
1447 @item Run @code{objcopy --strip-debug foo} to create a
1448 stripped executable.
1449 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
1450 to add a link to the debugging info into the stripped executable.
1453 Note - the choice of @code{.dbg} as an extension for the debug info
1454 file is arbitrary. Also the @code{--only-keep-debug} step is
1455 optional. You could instead do this:
1458 @item Link the executable as normal.
1459 @item Copy @code{foo} to @code{foo.full}
1460 @item Run @code{objcopy --strip-debug foo}
1461 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
1464 i.e. the file pointed to by the @option{--add-gnu-debuglink} can be the
1465 full executable. It does not have to be a file created by the
1466 @option{--only-keep-debug} switch.
1470 Show the version number of @command{objcopy}.
1474 Verbose output: list all object files modified. In the case of
1475 archives, @samp{objcopy -V} lists all members of the archive.
1478 Show a summary of the options to @command{objcopy}.
1481 Display a list showing all architectures and object formats available.
1487 @c man begin SEEALSO objcopy
1488 ld(1), objdump(1), and the Info entries for @file{binutils}.
1495 @cindex object file information
1498 @c man title objdump display information from object files.
1501 @c man begin SYNOPSIS objdump
1502 objdump [@option{-a}|@option{--archive-headers}]
1503 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
1504 [@option{-C}|@option{--demangle}[=@var{style}] ]
1505 [@option{-d}|@option{--disassemble}]
1506 [@option{-D}|@option{--disassemble-all}]
1507 [@option{-z}|@option{--disassemble-zeroes}]
1508 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
1509 [@option{-f}|@option{--file-headers}]
1510 [@option{--file-start-context}]
1511 [@option{-g}|@option{--debugging}]
1512 [@option{-e}|@option{--debugging-tags}]
1513 [@option{-h}|@option{--section-headers}|@option{--headers}]
1514 [@option{-i}|@option{--info}]
1515 [@option{-j} @var{section}|@option{--section=}@var{section}]
1516 [@option{-l}|@option{--line-numbers}]
1517 [@option{-S}|@option{--source}]
1518 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
1519 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
1520 [@option{-p}|@option{--private-headers}]
1521 [@option{-r}|@option{--reloc}]
1522 [@option{-R}|@option{--dynamic-reloc}]
1523 [@option{-s}|@option{--full-contents}]
1524 [@option{-G}|@option{--stabs}]
1525 [@option{-t}|@option{--syms}]
1526 [@option{-T}|@option{--dynamic-syms}]
1527 [@option{-x}|@option{--all-headers}]
1528 [@option{-w}|@option{--wide}]
1529 [@option{--start-address=}@var{address}]
1530 [@option{--stop-address=}@var{address}]
1531 [@option{--prefix-addresses}]
1532 [@option{--[no-]show-raw-insn}]
1533 [@option{--adjust-vma=}@var{offset}]
1534 [@option{--special-syms}]
1535 [@option{-V}|@option{--version}]
1536 [@option{-H}|@option{--help}]
1537 @var{objfile}@dots{}
1541 @c man begin DESCRIPTION objdump
1543 @command{objdump} displays information about one or more object files.
1544 The options control what particular information to display. This
1545 information is mostly useful to programmers who are working on the
1546 compilation tools, as opposed to programmers who just want their
1547 program to compile and work.
1549 @var{objfile}@dots{} are the object files to be examined. When you
1550 specify archives, @command{objdump} shows information on each of the member
1555 @c man begin OPTIONS objdump
1557 The long and short forms of options, shown here as alternatives, are
1558 equivalent. At least one option from the list
1559 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
1563 @itemx --archive-header
1564 @cindex archive headers
1565 If any of the @var{objfile} files are archives, display the archive
1566 header information (in a format similar to @samp{ls -l}). Besides the
1567 information you could list with @samp{ar tv}, @samp{objdump -a} shows
1568 the object file format of each archive member.
1570 @item --adjust-vma=@var{offset}
1571 @cindex section addresses in objdump
1572 @cindex VMA in objdump
1573 When dumping information, first add @var{offset} to all the section
1574 addresses. This is useful if the section addresses do not correspond to
1575 the symbol table, which can happen when putting sections at particular
1576 addresses when using a format which can not represent section addresses,
1579 @item -b @var{bfdname}
1580 @itemx --target=@var{bfdname}
1581 @cindex object code format
1582 Specify that the object-code format for the object files is
1583 @var{bfdname}. This option may not be necessary; @var{objdump} can
1584 automatically recognize many formats.
1588 objdump -b oasys -m vax -h fu.o
1591 displays summary information from the section headers (@option{-h}) of
1592 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
1593 file in the format produced by Oasys compilers. You can list the
1594 formats available with the @option{-i} option.
1595 @xref{Target Selection}, for more information.
1598 @itemx --demangle[=@var{style}]
1599 @cindex demangling in objdump
1600 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1601 Besides removing any initial underscore prepended by the system, this
1602 makes C++ function names readable. Different compilers have different
1603 mangling styles. The optional demangling style argument can be used to
1604 choose an appropriate demangling style for your compiler. @xref{c++filt},
1605 for more information on demangling.
1609 Display debugging information. This attempts to parse debugging
1610 information stored in the file and print it out using a C like syntax.
1611 Only certain types of debugging information have been implemented.
1612 Some other types are supported by @command{readelf -w}.
1616 @itemx --debugging-tags
1617 Like @option{-g}, but the information is generated in a format compatible
1621 @itemx --disassemble
1622 @cindex disassembling object code
1623 @cindex machine instructions
1624 Display the assembler mnemonics for the machine instructions from
1625 @var{objfile}. This option only disassembles those sections which are
1626 expected to contain instructions.
1629 @itemx --disassemble-all
1630 Like @option{-d}, but disassemble the contents of all sections, not just
1631 those expected to contain instructions.
1633 @item --prefix-addresses
1634 When disassembling, print the complete address on each line. This is
1635 the older disassembly format.
1639 @itemx --endian=@{big|little@}
1641 @cindex disassembly endianness
1642 Specify the endianness of the object files. This only affects
1643 disassembly. This can be useful when disassembling a file format which
1644 does not describe endianness information, such as S-records.
1647 @itemx --file-headers
1648 @cindex object file header
1649 Display summary information from the overall header of
1650 each of the @var{objfile} files.
1652 @item --file-start-context
1653 @cindex source code context
1654 Specify that when displaying interlisted source code/disassembly
1655 (assumes @option{-S}) from a file that has not yet been displayed, extend the
1656 context to the start of the file.
1659 @itemx --section-headers
1661 @cindex section headers
1662 Display summary information from the section headers of the
1665 File segments may be relocated to nonstandard addresses, for example by
1666 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
1667 @command{ld}. However, some object file formats, such as a.out, do not
1668 store the starting address of the file segments. In those situations,
1669 although @command{ld} relocates the sections correctly, using @samp{objdump
1670 -h} to list the file section headers cannot show the correct addresses.
1671 Instead, it shows the usual addresses, which are implicit for the
1676 Print a summary of the options to @command{objdump} and exit.
1680 @cindex architectures available
1681 @cindex object formats available
1682 Display a list showing all architectures and object formats available
1683 for specification with @option{-b} or @option{-m}.
1686 @itemx --section=@var{name}
1687 @cindex section information
1688 Display information only for section @var{name}.
1691 @itemx --line-numbers
1692 @cindex source filenames for object files
1693 Label the display (using debugging information) with the filename and
1694 source line numbers corresponding to the object code or relocs shown.
1695 Only useful with @option{-d}, @option{-D}, or @option{-r}.
1697 @item -m @var{machine}
1698 @itemx --architecture=@var{machine}
1699 @cindex architecture
1700 @cindex disassembly architecture
1701 Specify the architecture to use when disassembling object files. This
1702 can be useful when disassembling object files which do not describe
1703 architecture information, such as S-records. You can list the available
1704 architectures with the @option{-i} option.
1706 @item -M @var{options}
1707 @itemx --disassembler-options=@var{options}
1708 Pass target specific information to the disassembler. Only supported on
1709 some targets. If it is necessary to specify more than one
1710 disassembler option then multiple @option{-M} options can be used or
1711 can be placed together into a comma separated list.
1713 If the target is an ARM architecture then this switch can be used to
1714 select which register name set is used during disassembler. Specifying
1715 @option{-M reg-name-std} (the default) will select the register names as
1716 used in ARM's instruction set documentation, but with register 13 called
1717 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
1718 @option{-M reg-names-apcs} will select the name set used by the ARM
1719 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
1720 just use @samp{r} followed by the register number.
1722 There are also two variants on the APCS register naming scheme enabled
1723 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
1724 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
1725 with the normal register names or the special register names).
1727 This option can also be used for ARM architectures to force the
1728 disassembler to interpret all instructions as Thumb instructions by
1729 using the switch @option{--disassembler-options=force-thumb}. This can be
1730 useful when attempting to disassemble thumb code produced by other
1733 For the x86, some of the options duplicate functions of the @option{-m}
1734 switch, but allow finer grained control. Multiple selections from the
1735 following may be specified as a comma separated string.
1736 @option{x86-64}, @option{i386} and @option{i8086} select disassembly for
1737 the given architecture. @option{intel} and @option{att} select between
1738 intel syntax mode and AT&T syntax mode. @option{addr32},
1739 @option{addr16}, @option{data32} and @option{data16} specify the default
1740 address size and operand size. These four options will be overridden if
1741 @option{x86-64}, @option{i386} or @option{i8086} appear later in the
1742 option string. Lastly, @option{suffix}, when in AT&T mode,
1743 instructs the disassembler to print a mnemonic suffix even when the
1744 suffix could be inferred by the operands.
1746 For PPC, @option{booke}, @option{booke32} and @option{booke64} select
1747 disassembly of BookE instructions. @option{32} and @option{64} select
1748 PowerPC and PowerPC64 disassembly, respectively. @option{e300} selects
1749 disassembly for the e300 family.
1751 For MIPS, this option controls the printing of instruction mneumonic
1752 names and register names in disassembled instructions. Multiple
1753 selections from the following may be specified as a comma separated
1754 string, and invalid options are ignored:
1758 Print the 'raw' instruction mneumonic instead of some pseudo
1759 instruction mneumonic. I.E. print 'daddu' or 'or' instead of 'move',
1760 'sll' instead of 'nop', etc.
1762 @item gpr-names=@var{ABI}
1763 Print GPR (general-purpose register) names as appropriate
1764 for the specified ABI. By default, GPR names are selected according to
1765 the ABI of the binary being disassembled.
1767 @item fpr-names=@var{ABI}
1768 Print FPR (floating-point register) names as
1769 appropriate for the specified ABI. By default, FPR numbers are printed
1772 @item cp0-names=@var{ARCH}
1773 Print CP0 (system control coprocessor; coprocessor 0) register names
1774 as appropriate for the CPU or architecture specified by
1775 @var{ARCH}. By default, CP0 register names are selected according to
1776 the architecture and CPU of the binary being disassembled.
1778 @item hwr-names=@var{ARCH}
1779 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
1780 as appropriate for the CPU or architecture specified by
1781 @var{ARCH}. By default, HWR names are selected according to
1782 the architecture and CPU of the binary being disassembled.
1784 @item reg-names=@var{ABI}
1785 Print GPR and FPR names as appropriate for the selected ABI.
1787 @item reg-names=@var{ARCH}
1788 Print CPU-specific register names (CP0 register and HWR names)
1789 as appropriate for the selected CPU or architecture.
1792 For any of the options listed above, @var{ABI} or
1793 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
1794 rather than names, for the selected types of registers.
1795 You can list the available values of @var{ABI} and @var{ARCH} using
1796 the @option{--help} option.
1798 For VAX, you can specify function entry addresses with @option{-M
1799 entry:0xf00ba}. You can use this multiple times to properly
1800 disassemble VAX binary files that don't contain symbol tables (like
1801 ROM dumps). In these cases, the function entry mask would otherwise
1802 be decoded as VAX instructions, which would probably lead the the rest
1803 of the function being wrongly disassembled.
1806 @itemx --private-headers
1807 Print information that is specific to the object file format. The exact
1808 information printed depends upon the object file format. For some
1809 object file formats, no additional information is printed.
1813 @cindex relocation entries, in object file
1814 Print the relocation entries of the file. If used with @option{-d} or
1815 @option{-D}, the relocations are printed interspersed with the
1819 @itemx --dynamic-reloc
1820 @cindex dynamic relocation entries, in object file
1821 Print the dynamic relocation entries of the file. This is only
1822 meaningful for dynamic objects, such as certain types of shared
1826 @itemx --full-contents
1827 @cindex sections, full contents
1828 @cindex object file sections
1829 Display the full contents of any sections requested. By default all
1830 non-empty sections are displayed.
1834 @cindex source disassembly
1835 @cindex disassembly, with source
1836 Display source code intermixed with disassembly, if possible. Implies
1839 @item --show-raw-insn
1840 When disassembling instructions, print the instruction in hex as well as
1841 in symbolic form. This is the default except when
1842 @option{--prefix-addresses} is used.
1844 @item --no-show-raw-insn
1845 When disassembling instructions, do not print the instruction bytes.
1846 This is the default when @option{--prefix-addresses} is used.
1852 @cindex debug symbols
1853 @cindex ELF object file format
1854 Display the full contents of any sections requested. Display the
1855 contents of the .stab and .stab.index and .stab.excl sections from an
1856 ELF file. This is only useful on systems (such as Solaris 2.0) in which
1857 @code{.stab} debugging symbol-table entries are carried in an ELF
1858 section. In most other file formats, debugging symbol-table entries are
1859 interleaved with linkage symbols, and are visible in the @option{--syms}
1862 For more information on stabs symbols, see @ref{Top,Stabs,Stabs
1863 Overview,stabs.info, The ``stabs'' debug format}.
1866 @item --start-address=@var{address}
1867 @cindex start-address
1868 Start displaying data at the specified address. This affects the output
1869 of the @option{-d}, @option{-r} and @option{-s} options.
1871 @item --stop-address=@var{address}
1872 @cindex stop-address
1873 Stop displaying data at the specified address. This affects the output
1874 of the @option{-d}, @option{-r} and @option{-s} options.
1878 @cindex symbol table entries, printing
1879 Print the symbol table entries of the file.
1880 This is similar to the information provided by the @samp{nm} program.
1883 @itemx --dynamic-syms
1884 @cindex dynamic symbol table entries, printing
1885 Print the dynamic symbol table entries of the file. This is only
1886 meaningful for dynamic objects, such as certain types of shared
1887 libraries. This is similar to the information provided by the @samp{nm}
1888 program when given the @option{-D} (@option{--dynamic}) option.
1890 @item --special-syms
1891 When displaying symbols include those which the target considers to be
1892 special in some way and which would not normally be of interest to the
1897 Print the version number of @command{objdump} and exit.
1900 @itemx --all-headers
1901 @cindex all header information, object file
1902 @cindex header information, all
1903 Display all available header information, including the symbol table and
1904 relocation entries. Using @option{-x} is equivalent to specifying all of
1905 @option{-a -f -h -p -r -t}.
1909 @cindex wide output, printing
1910 Format some lines for output devices that have more than 80 columns.
1911 Also do not truncate symbol names when they are displayed.
1914 @itemx --disassemble-zeroes
1915 Normally the disassembly output will skip blocks of zeroes. This
1916 option directs the disassembler to disassemble those blocks, just like
1923 @c man begin SEEALSO objdump
1924 nm(1), readelf(1), and the Info entries for @file{binutils}.
1932 @cindex archive contents
1933 @cindex symbol index
1935 @c man title ranlib generate index to archive.
1938 @c man begin SYNOPSIS ranlib
1939 ranlib [@option{-vV}] @var{archive}
1943 @c man begin DESCRIPTION ranlib
1945 @command{ranlib} generates an index to the contents of an archive and
1946 stores it in the archive. The index lists each symbol defined by a
1947 member of an archive that is a relocatable object file.
1949 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
1951 An archive with such an index speeds up linking to the library and
1952 allows routines in the library to call each other without regard to
1953 their placement in the archive.
1955 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
1956 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
1961 @c man begin OPTIONS ranlib
1967 Show the version number of @command{ranlib}.
1973 @c man begin SEEALSO ranlib
1974 ar(1), nm(1), and the Info entries for @file{binutils}.
1982 @cindex section sizes
1984 @c man title size list section sizes and total size.
1987 @c man begin SYNOPSIS size
1988 size [@option{-A}|@option{-B}|@option{--format=}@var{compatibility}]
1990 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
1991 [@option{-t}|@option{--totals}]
1992 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
1993 [@var{objfile}@dots{}]
1997 @c man begin DESCRIPTION size
1999 The @sc{gnu} @command{size} utility lists the section sizes---and the total
2000 size---for each of the object or archive files @var{objfile} in its
2001 argument list. By default, one line of output is generated for each
2002 object file or each module in an archive.
2004 @var{objfile}@dots{} are the object files to be examined.
2005 If none are specified, the file @code{a.out} will be used.
2009 @c man begin OPTIONS size
2011 The command line options have the following meanings:
2016 @itemx --format=@var{compatibility}
2017 @cindex @command{size} display format
2018 Using one of these options, you can choose whether the output from @sc{gnu}
2019 @command{size} resembles output from System V @command{size} (using @option{-A},
2020 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
2021 @option{--format=berkeley}). The default is the one-line format similar to
2023 @c Bonus for doc-source readers: you can also say --format=strange (or
2024 @c anything else that starts with 's') for sysv, and --format=boring (or
2025 @c anything else that starts with 'b') for Berkeley.
2027 Here is an example of the Berkeley (default) format of output from
2030 $ size --format=Berkeley ranlib size
2031 text data bss dec hex filename
2032 294880 81920 11592 388392 5ed28 ranlib
2033 294880 81920 11888 388688 5ee50 size
2037 This is the same data, but displayed closer to System V conventions:
2040 $ size --format=SysV ranlib size
2058 Show a summary of acceptable arguments and options.
2063 @itemx --radix=@var{number}
2064 @cindex @command{size} number format
2065 @cindex radix for section sizes
2066 Using one of these options, you can control whether the size of each
2067 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
2068 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
2069 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
2070 values (8, 10, 16) are supported. The total size is always given in two
2071 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
2072 octal and hexadecimal if you're using @option{-o}.
2076 Show totals of all objects listed (Berkeley format listing mode only).
2078 @item --target=@var{bfdname}
2079 @cindex object code format
2080 Specify that the object-code format for @var{objfile} is
2081 @var{bfdname}. This option may not be necessary; @command{size} can
2082 automatically recognize many formats.
2083 @xref{Target Selection}, for more information.
2087 Display the version number of @command{size}.
2093 @c man begin SEEALSO size
2094 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
2101 @cindex listings strings
2102 @cindex printing strings
2103 @cindex strings, printing
2105 @c man title strings print the strings of printable characters in files.
2108 @c man begin SYNOPSIS strings
2109 strings [@option{-afov}] [@option{-}@var{min-len}]
2110 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
2111 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
2112 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
2113 [@option{-}] [@option{--all}] [@option{--print-file-name}]
2114 [@option{--target=}@var{bfdname}]
2115 [@option{--help}] [@option{--version}] @var{file}@dots{}
2119 @c man begin DESCRIPTION strings
2121 For each @var{file} given, @sc{gnu} @command{strings} prints the printable
2122 character sequences that are at least 4 characters long (or the number
2123 given with the options below) and are followed by an unprintable
2124 character. By default, it only prints the strings from the initialized
2125 and loaded sections of object files; for other types of files, it prints
2126 the strings from the whole file.
2128 @command{strings} is mainly useful for determining the contents of non-text
2133 @c man begin OPTIONS strings
2139 Do not scan only the initialized and loaded sections of object files;
2140 scan the whole files.
2143 @itemx --print-file-name
2144 Print the name of the file before each string.
2147 Print a summary of the program usage on the standard output and exit.
2149 @item -@var{min-len}
2150 @itemx -n @var{min-len}
2151 @itemx --bytes=@var{min-len}
2152 Print sequences of characters that are at least @var{min-len} characters
2153 long, instead of the default 4.
2156 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
2157 act like @samp{-t d} instead. Since we can not be compatible with both
2158 ways, we simply chose one.
2160 @item -t @var{radix}
2161 @itemx --radix=@var{radix}
2162 Print the offset within the file before each string. The single
2163 character argument specifies the radix of the offset---@samp{o} for
2164 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
2166 @item -e @var{encoding}
2167 @itemx --encoding=@var{encoding}
2168 Select the character encoding of the strings that are to be found.
2169 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
2170 characters (ASCII, ISO 8859, etc., default), @samp{S} =
2171 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
2172 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
2173 littleendian. Useful for finding wide character strings.
2175 @item --target=@var{bfdname}
2176 @cindex object code format
2177 Specify an object code format other than your system's default format.
2178 @xref{Target Selection}, for more information.
2182 Print the program version number on the standard output and exit.
2188 @c man begin SEEALSO strings
2189 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
2190 and the Info entries for @file{binutils}.
2198 @cindex removing symbols
2199 @cindex discarding symbols
2200 @cindex symbols, discarding
2202 @c man title strip Discard symbols from object files.
2205 @c man begin SYNOPSIS strip
2206 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
2207 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
2208 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
2209 [@option{-s}|@option{--strip-all}]
2210 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
2211 [@option{-K} @var{symbolname} |@option{--keep-symbol=}@var{symbolname}]
2212 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
2213 [@option{-w}|@option{--wildcard}]
2214 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
2215 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
2216 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
2217 [@option{--only-keep-debug}]
2218 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
2219 [@option{--help}] [@option{--info}]
2220 @var{objfile}@dots{}
2224 @c man begin DESCRIPTION strip
2226 @sc{gnu} @command{strip} discards all symbols from object files
2227 @var{objfile}. The list of object files may include archives.
2228 At least one object file must be given.
2230 @command{strip} modifies the files named in its argument,
2231 rather than writing modified copies under different names.
2235 @c man begin OPTIONS strip
2238 @item -F @var{bfdname}
2239 @itemx --target=@var{bfdname}
2240 Treat the original @var{objfile} as a file with the object
2241 code format @var{bfdname}, and rewrite it in the same format.
2242 @xref{Target Selection}, for more information.
2245 Show a summary of the options to @command{strip} and exit.
2248 Display a list showing all architectures and object formats available.
2250 @item -I @var{bfdname}
2251 @itemx --input-target=@var{bfdname}
2252 Treat the original @var{objfile} as a file with the object
2253 code format @var{bfdname}.
2254 @xref{Target Selection}, for more information.
2256 @item -O @var{bfdname}
2257 @itemx --output-target=@var{bfdname}
2258 Replace @var{objfile} with a file in the output format @var{bfdname}.
2259 @xref{Target Selection}, for more information.
2261 @item -R @var{sectionname}
2262 @itemx --remove-section=@var{sectionname}
2263 Remove any section named @var{sectionname} from the output file. This
2264 option may be given more than once. Note that using this option
2265 inappropriately may make the output file unusable.
2274 @itemx --strip-debug
2275 Remove debugging symbols only.
2277 @item --strip-unneeded
2278 Remove all symbols that are not needed for relocation processing.
2280 @item -K @var{symbolname}
2281 @itemx --keep-symbol=@var{symbolname}
2282 When stripping symbols, keep symbol @var{symbolname} even if it would
2283 normally be stripped. This option may be given more than once.
2285 @item -N @var{symbolname}
2286 @itemx --strip-symbol=@var{symbolname}
2287 Remove symbol @var{symbolname} from the source file. This option may be
2288 given more than once, and may be combined with strip options other than
2292 Put the stripped output in @var{file}, rather than replacing the
2293 existing file. When this argument is used, only one @var{objfile}
2294 argument may be specified.
2297 @itemx --preserve-dates
2298 Preserve the access and modification dates of the file.
2302 Permit regular expressions in @var{symbolname}s used in other command
2303 line options. The question mark (?), asterisk (*), backslash (\) and
2304 square brackets ([]) operators can be used anywhere in the symbol
2305 name. If the first character of the symbol name is the exclamation
2306 point (!) then the sense of the switch is reversed for that symbol.
2313 would cause strip to only keep symbols that start with the letters
2314 ``fo'', but to discard the symbol ``foo''.
2317 @itemx --discard-all
2318 Remove non-global symbols.
2321 @itemx --discard-locals
2322 Remove compiler-generated local symbols.
2323 (These usually start with @samp{L} or @samp{.}.)
2325 @item --only-keep-debug
2326 Strip a file, removing any sections that would be stripped by
2327 @option{--strip-debug} and leaving the debugging sections.
2329 The intention is that this option will be used in conjunction with
2330 @option{--add-gnu-debuglink} to create a two part executable. One a
2331 stripped binary which will occupy less space in RAM and in a
2332 distribution and the second a debugging information file which is only
2333 needed if debugging abilities are required. The suggested procedure
2334 to create these files is as follows:
2337 @item Link the executable as normal. Assuming that is is called
2339 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
2340 create a file containing the debugging info.
2341 @item Run @code{objcopy --strip-debug foo} to create a
2342 stripped executable.
2343 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
2344 to add a link to the debugging info into the stripped executable.
2347 Note - the choice of @code{.dbg} as an extension for the debug info
2348 file is arbitrary. Also the @code{--only-keep-debug} step is
2349 optional. You could instead do this:
2352 @item Link the executable as normal.
2353 @item Copy @code{foo} to @code{foo.full}
2354 @item Run @code{strip --strip-debug foo}
2355 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
2358 ie the file pointed to by the @option{--add-gnu-debuglink} can be the
2359 full executable. It does not have to be a file created by the
2360 @option{--only-keep-debug} switch.
2364 Show the version number for @command{strip}.
2368 Verbose output: list all object files modified. In the case of
2369 archives, @samp{strip -v} lists all members of the archive.
2375 @c man begin SEEALSO strip
2376 the Info entries for @file{binutils}.
2380 @node c++filt, addr2line, strip, Top
2384 @cindex demangling C++ symbols
2386 @c man title cxxfilt Demangle C++ and Java symbols.
2389 @c man begin SYNOPSIS cxxfilt
2390 c++filt [@option{-_}|@option{--strip-underscores}]
2391 [@option{-j}|@option{--java}]
2392 [@option{-n}|@option{--no-strip-underscores}]
2393 [@option{-p}|@option{--no-params}]
2394 [@option{-s} @var{format}|@option{--format=}@var{format}]
2395 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
2399 @c man begin DESCRIPTION cxxfilt
2402 The C++ and Java languages provides function overloading, which means
2403 that you can write many functions with the same name (providing each
2404 takes parameters of different types). All C++ and Java function names
2405 are encoded into a low-level assembly label (this process is known as
2406 @dfn{mangling}). The @command{c++filt}
2407 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
2408 MS-DOS this program is named @command{CXXFILT}.}
2409 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
2410 names into user-level names so that the linker can keep these overloaded
2411 functions from clashing.
2413 Every alphanumeric word (consisting of letters, digits, underscores,
2414 dollars, or periods) seen in the input is a potential label. If the
2415 label decodes into a C++ name, the C++ name replaces the low-level
2418 You can use @command{c++filt} to decipher individual symbols:
2421 c++filt @var{symbol}
2424 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
2425 names from the standard input and writes the demangled names to the
2426 standard output. All results are printed on the standard output.
2430 @c man begin OPTIONS cxxfilt
2434 @itemx --strip-underscores
2435 On some systems, both the C and C++ compilers put an underscore in front
2436 of every name. For example, the C name @code{foo} gets the low-level
2437 name @code{_foo}. This option removes the initial underscore. Whether
2438 @command{c++filt} removes the underscore by default is target dependent.
2442 Prints demangled names using Java syntax. The default is to use C++
2446 @itemx --no-strip-underscores
2447 Do not remove the initial underscore.
2451 When demangling the name of a function, do not display the types of
2452 the function's parameters.
2454 @item -s @var{format}
2455 @itemx --format=@var{format}
2456 @command{c++filt} can decode various methods of mangling, used by
2457 different compilers. The argument to this option selects which
2462 Automatic selection based on executable (the default method)
2464 the one used by the @sc{gnu} C++ compiler (g++)
2466 the one used by the Lucid compiler (lcc)
2468 the one specified by the C++ Annotated Reference Manual
2470 the one used by the HP compiler (aCC)
2472 the one used by the EDG compiler
2474 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
2476 the one used by the @sc{gnu} Java compiler (gcj)
2478 the one used by the @sc{gnu} Ada compiler (GNAT).
2482 Print a summary of the options to @command{c++filt} and exit.
2485 Print the version number of @command{c++filt} and exit.
2491 @c man begin SEEALSO cxxfilt
2492 the Info entries for @file{binutils}.
2497 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
2498 user interface are subject to change in future releases. In particular,
2499 a command-line option may be required in the the future to decode a name
2500 passed as an argument on the command line; in other words,
2503 c++filt @var{symbol}
2507 may in a future release become
2510 c++filt @var{option} @var{symbol}
2518 @cindex address to file name and line number
2520 @c man title addr2line convert addresses into file names and line numbers.
2523 @c man begin SYNOPSIS addr2line
2524 addr2line [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
2525 [@option{-C}|@option{--demangle}[=@var{style}]]
2526 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
2527 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
2528 [@option{-i}|@option{--inlines}]
2529 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
2534 @c man begin DESCRIPTION addr2line
2536 @command{addr2line} translates program addresses into file names and line
2537 numbers. Given an address and an executable, it uses the debugging
2538 information in the executable to figure out which file name and line
2539 number are associated with a given address.
2541 The executable to use is specified with the @option{-e} option. The
2542 default is the file @file{a.out}.
2544 @command{addr2line} has two modes of operation.
2546 In the first, hexadecimal addresses are specified on the command line,
2547 and @command{addr2line} displays the file name and line number for each
2550 In the second, @command{addr2line} reads hexadecimal addresses from
2551 standard input, and prints the file name and line number for each
2552 address on standard output. In this mode, @command{addr2line} may be used
2553 in a pipe to convert dynamically chosen addresses.
2555 The format of the output is @samp{FILENAME:LINENO}. The file name and
2556 line number for each address is printed on a separate line. If the
2557 @command{-f} option is used, then each @samp{FILENAME:LINENO} line is
2558 preceded by a @samp{FUNCTIONNAME} line which is the name of the function
2559 containing the address.
2561 If the file name or function name can not be determined,
2562 @command{addr2line} will print two question marks in their place. If the
2563 line number can not be determined, @command{addr2line} will print 0.
2567 @c man begin OPTIONS addr2line
2569 The long and short forms of options, shown here as alternatives, are
2573 @item -b @var{bfdname}
2574 @itemx --target=@var{bfdname}
2575 @cindex object code format
2576 Specify that the object-code format for the object files is
2580 @itemx --demangle[=@var{style}]
2581 @cindex demangling in objdump
2582 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2583 Besides removing any initial underscore prepended by the system, this
2584 makes C++ function names readable. Different compilers have different
2585 mangling styles. The optional demangling style argument can be used to
2586 choose an appropriate demangling style for your compiler. @xref{c++filt},
2587 for more information on demangling.
2589 @item -e @var{filename}
2590 @itemx --exe=@var{filename}
2591 Specify the name of the executable for which addresses should be
2592 translated. The default file is @file{a.out}.
2596 Display function names as well as file and line number information.
2600 Display only the base of each file name.
2604 If the address belongs to a function that was inlined, the source
2605 information for all enclosing scopes back to the first non-inlined
2606 function will also be printed. For example, if @code{main} inlines
2607 @code{callee1} which inlines @code{callee2}, and address is from
2608 @code{callee2}, the source information for @code{callee1} and @code{main}
2609 will also be printed.
2615 @c man begin SEEALSO addr2line
2616 Info entries for @file{binutils}.
2623 @command{nlmconv} converts a relocatable object file into a NetWare
2627 @command{nlmconv} currently works with @samp{i386} object
2628 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
2629 object files in @sc{elf}, or @code{a.out} format@footnote{
2630 @command{nlmconv} should work with any @samp{i386} or @sc{sparc} object
2631 format in the Binary File Descriptor library. It has only been tested
2632 with the above formats.}.
2636 @emph{Warning:} @command{nlmconv} is not always built as part of the binary
2637 utilities, since it is only useful for NLM targets.
2640 @c man title nlmconv converts object code into an NLM.
2643 @c man begin SYNOPSIS nlmconv
2644 nlmconv [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
2645 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
2646 [@option{-T} @var{headerfile}|@option{--header-file=}@var{headerfile}]
2647 [@option{-d}|@option{--debug}] [@option{-l} @var{linker}|@option{--linker=}@var{linker}]
2648 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
2649 @var{infile} @var{outfile}
2653 @c man begin DESCRIPTION nlmconv
2655 @command{nlmconv} converts the relocatable @samp{i386} object file
2656 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
2657 reading @var{headerfile} for NLM header information. For instructions
2658 on writing the NLM command file language used in header files, see the
2659 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
2660 Development and Tools Overview}, which is part of the NLM Software
2661 Developer's Kit (``NLM SDK''), available from Novell, Inc.
2662 @command{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
2665 see @ref{BFD,,BFD,ld.info,Using LD}, for more information.
2668 @command{nlmconv} can perform a link step. In other words, you can list
2669 more than one object file for input if you list them in the definitions
2670 file (rather than simply specifying one input file on the command line).
2671 In this case, @command{nlmconv} calls the linker for you.
2675 @c man begin OPTIONS nlmconv
2678 @item -I @var{bfdname}
2679 @itemx --input-target=@var{bfdname}
2680 Object format of the input file. @command{nlmconv} can usually determine
2681 the format of a given file (so no default is necessary).
2682 @xref{Target Selection}, for more information.
2684 @item -O @var{bfdname}
2685 @itemx --output-target=@var{bfdname}
2686 Object format of the output file. @command{nlmconv} infers the output
2687 format based on the input format, e.g. for a @samp{i386} input file the
2688 output format is @samp{nlm32-i386}.
2689 @xref{Target Selection}, for more information.
2691 @item -T @var{headerfile}
2692 @itemx --header-file=@var{headerfile}
2693 Reads @var{headerfile} for NLM header information. For instructions on
2694 writing the NLM command file language used in header files, see@ see the
2695 @samp{linkers} section, of the @cite{NLM Development and Tools
2696 Overview}, which is part of the NLM Software Developer's Kit, available
2701 Displays (on standard error) the linker command line used by @command{nlmconv}.
2703 @item -l @var{linker}
2704 @itemx --linker=@var{linker}
2705 Use @var{linker} for any linking. @var{linker} can be an absolute or a
2710 Prints a usage summary.
2714 Prints the version number for @command{nlmconv}.
2720 @c man begin SEEALSO nlmconv
2721 the Info entries for @file{binutils}.
2728 @command{windres} may be used to manipulate Windows resources.
2731 @emph{Warning:} @command{windres} is not always built as part of the binary
2732 utilities, since it is only useful for Windows targets.
2735 @c man title windres manipulate Windows resources.
2738 @c man begin SYNOPSIS windres
2739 windres [options] [input-file] [output-file]
2743 @c man begin DESCRIPTION windres
2745 @command{windres} reads resources from an input file and copies them into
2746 an output file. Either file may be in one of three formats:
2750 A text format read by the Resource Compiler.
2753 A binary format generated by the Resource Compiler.
2756 A COFF object or executable.
2759 The exact description of these different formats is available in
2760 documentation from Microsoft.
2762 When @command{windres} converts from the @code{rc} format to the @code{res}
2763 format, it is acting like the Windows Resource Compiler. When
2764 @command{windres} converts from the @code{res} format to the @code{coff}
2765 format, it is acting like the Windows @code{CVTRES} program.
2767 When @command{windres} generates an @code{rc} file, the output is similar
2768 but not identical to the format expected for the input. When an input
2769 @code{rc} file refers to an external filename, an output @code{rc} file
2770 will instead include the file contents.
2772 If the input or output format is not specified, @command{windres} will
2773 guess based on the file name, or, for the input file, the file contents.
2774 A file with an extension of @file{.rc} will be treated as an @code{rc}
2775 file, a file with an extension of @file{.res} will be treated as a
2776 @code{res} file, and a file with an extension of @file{.o} or
2777 @file{.exe} will be treated as a @code{coff} file.
2779 If no output file is specified, @command{windres} will print the resources
2780 in @code{rc} format to standard output.
2782 The normal use is for you to write an @code{rc} file, use @command{windres}
2783 to convert it to a COFF object file, and then link the COFF file into
2784 your application. This will make the resources described in the
2785 @code{rc} file available to Windows.
2789 @c man begin OPTIONS windres
2792 @item -i @var{filename}
2793 @itemx --input @var{filename}
2794 The name of the input file. If this option is not used, then
2795 @command{windres} will use the first non-option argument as the input file
2796 name. If there are no non-option arguments, then @command{windres} will
2797 read from standard input. @command{windres} can not read a COFF file from
2800 @item -o @var{filename}
2801 @itemx --output @var{filename}
2802 The name of the output file. If this option is not used, then
2803 @command{windres} will use the first non-option argument, after any used
2804 for the input file name, as the output file name. If there is no
2805 non-option argument, then @command{windres} will write to standard output.
2806 @command{windres} can not write a COFF file to standard output. Note,
2807 for compatability with @command{rc} the option @option{-fo} is also
2808 accepted, but its use is not recommended.
2810 @item -J @var{format}
2811 @itemx --input-format @var{format}
2812 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
2813 @samp{coff}. If no input format is specified, @command{windres} will
2814 guess, as described above.
2816 @item -O @var{format}
2817 @itemx --output-format @var{format}
2818 The output format to generate. @var{format} may be @samp{res},
2819 @samp{rc}, or @samp{coff}. If no output format is specified,
2820 @command{windres} will guess, as described above.
2822 @item -F @var{target}
2823 @itemx --target @var{target}
2824 Specify the BFD format to use for a COFF file as input or output. This
2825 is a BFD target name; you can use the @option{--help} option to see a list
2826 of supported targets. Normally @command{windres} will use the default
2827 format, which is the first one listed by the @option{--help} option.
2829 @ref{Target Selection}.
2832 @item --preprocessor @var{program}
2833 When @command{windres} reads an @code{rc} file, it runs it through the C
2834 preprocessor first. This option may be used to specify the preprocessor
2835 to use, including any leading arguments. The default preprocessor
2836 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
2838 @item -I @var{directory}
2839 @itemx --include-dir @var{directory}
2840 Specify an include directory to use when reading an @code{rc} file.
2841 @command{windres} will pass this to the preprocessor as an @option{-I}
2842 option. @command{windres} will also search this directory when looking for
2843 files named in the @code{rc} file. If the argument passed to this command
2844 matches any of the supported @var{formats} (as descrived in the @option{-J}
2845 option), it will issue a deprecation warning, and behave just like the
2846 @option{-J} option. New programs should not use this behaviour. If a
2847 directory happens to match a @var{format}, simple prefix it with @samp{./}
2848 to disable the backward compatibility.
2850 @item -D @var{target}
2851 @itemx --define @var{sym}[=@var{val}]
2852 Specify a @option{-D} option to pass to the preprocessor when reading an
2855 @item -U @var{target}
2856 @itemx --undefine @var{sym}
2857 Specify a @option{-U} option to pass to the preprocessor when reading an
2861 Ignored for compatibility with rc.
2864 Enable verbose mode. This tells you what the preprocessor is if you
2868 @item --language @var{val}
2869 Specify the default language to use when reading an @code{rc} file.
2870 @var{val} should be a hexadecimal language code. The low eight bits are
2871 the language, and the high eight bits are the sublanguage.
2873 @item --use-temp-file
2874 Use a temporary file to instead of using popen to read the output of
2875 the preprocessor. Use this option if the popen implementation is buggy
2876 on the host (eg., certain non-English language versions of Windows 95 and
2877 Windows 98 are known to have buggy popen where the output will instead
2880 @item --no-use-temp-file
2881 Use popen, not a temporary file, to read the output of the preprocessor.
2882 This is the default behaviour.
2886 Prints a usage summary.
2890 Prints the version number for @command{windres}.
2893 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
2894 this will turn on parser debugging.
2900 @c man begin SEEALSO windres
2901 the Info entries for @file{binutils}.
2910 @command{dlltool} is used to create the files needed to create dynamic
2911 link libraries (DLLs) on systems which understand PE format image
2912 files such as Windows. A DLL contains an export table which contains
2913 information that the runtime loader needs to resolve references from a
2914 referencing program.
2916 The export table is generated by this program by reading in a
2917 @file{.def} file or scanning the @file{.a} and @file{.o} files which
2918 will be in the DLL. A @file{.o} file can contain information in
2919 special @samp{.drectve} sections with export information.
2922 @emph{Note:} @command{dlltool} is not always built as part of the
2923 binary utilities, since it is only useful for those targets which
2927 @c man title dlltool Create files needed to build and use DLLs.
2930 @c man begin SYNOPSIS dlltool
2931 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
2932 [@option{-b}|@option{--base-file} @var{base-file-name}]
2933 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
2934 [@option{-z}|@option{--output-def} @var{def-file-name}]
2935 [@option{-l}|@option{--output-lib} @var{library-file-name}]
2936 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
2937 [@option{--exclude-symbols} @var{list}]
2938 [@option{--no-default-excludes}]
2939 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
2940 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
2941 [@option{-a}|@option{--add-indirect}] [@option{-U}|@option{--add-underscore}] [@option{-k}|@option{--kill-at}]
2942 [@option{-A}|@option{--add-stdcall-alias}]
2943 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
2944 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}] [@option{-i}|@option{--interwork}]
2945 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
2946 [@option{-v}|@option{--verbose}]
2947 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
2948 [object-file @dots{}]
2952 @c man begin DESCRIPTION dlltool
2954 @command{dlltool} reads its inputs, which can come from the @option{-d} and
2955 @option{-b} options as well as object files specified on the command
2956 line. It then processes these inputs and if the @option{-e} option has
2957 been specified it creates a exports file. If the @option{-l} option
2958 has been specified it creates a library file and if the @option{-z} option
2959 has been specified it creates a def file. Any or all of the @option{-e},
2960 @option{-l} and @option{-z} options can be present in one invocation of
2963 When creating a DLL, along with the source for the DLL, it is necessary
2964 to have three other files. @command{dlltool} can help with the creation of
2967 The first file is a @file{.def} file which specifies which functions are
2968 exported from the DLL, which functions the DLL imports, and so on. This
2969 is a text file and can be created by hand, or @command{dlltool} can be used
2970 to create it using the @option{-z} option. In this case @command{dlltool}
2971 will scan the object files specified on its command line looking for
2972 those functions which have been specially marked as being exported and
2973 put entries for them in the @file{.def} file it creates.
2975 In order to mark a function as being exported from a DLL, it needs to
2976 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
2977 section of the object file. This can be done in C by using the
2981 asm (".section .drectve");
2982 asm (".ascii \"-export:my_func\"");
2984 int my_func (void) @{ @dots{} @}
2987 The second file needed for DLL creation is an exports file. This file
2988 is linked with the object files that make up the body of the DLL and it
2989 handles the interface between the DLL and the outside world. This is a
2990 binary file and it can be created by giving the @option{-e} option to
2991 @command{dlltool} when it is creating or reading in a @file{.def} file.
2993 The third file needed for DLL creation is the library file that programs
2994 will link with in order to access the functions in the DLL. This file
2995 can be created by giving the @option{-l} option to dlltool when it
2996 is creating or reading in a @file{.def} file.
2998 @command{dlltool} builds the library file by hand, but it builds the
2999 exports file by creating temporary files containing assembler statements
3000 and then assembling these. The @option{-S} command line option can be
3001 used to specify the path to the assembler that dlltool will use,
3002 and the @option{-f} option can be used to pass specific flags to that
3003 assembler. The @option{-n} can be used to prevent dlltool from deleting
3004 these temporary assembler files when it is done, and if @option{-n} is
3005 specified twice then this will prevent dlltool from deleting the
3006 temporary object files it used to build the library.
3008 Here is an example of creating a DLL from a source file @samp{dll.c} and
3009 also creating a program (from an object file called @samp{program.o})
3014 dlltool -e exports.o -l dll.lib dll.o
3015 gcc dll.o exports.o -o dll.dll
3016 gcc program.o dll.lib -o program
3021 @c man begin OPTIONS dlltool
3023 The command line options have the following meanings:
3027 @item -d @var{filename}
3028 @itemx --input-def @var{filename}
3029 @cindex input .def file
3030 Specifies the name of a @file{.def} file to be read in and processed.
3032 @item -b @var{filename}
3033 @itemx --base-file @var{filename}
3035 Specifies the name of a base file to be read in and processed. The
3036 contents of this file will be added to the relocation section in the
3037 exports file generated by dlltool.
3039 @item -e @var{filename}
3040 @itemx --output-exp @var{filename}
3041 Specifies the name of the export file to be created by dlltool.
3043 @item -z @var{filename}
3044 @itemx --output-def @var{filename}
3045 Specifies the name of the @file{.def} file to be created by dlltool.
3047 @item -l @var{filename}
3048 @itemx --output-lib @var{filename}
3049 Specifies the name of the library file to be created by dlltool.
3051 @item --export-all-symbols
3052 Treat all global and weak defined symbols found in the input object
3053 files as symbols to be exported. There is a small list of symbols which
3054 are not exported by default; see the @option{--no-default-excludes}
3055 option. You may add to the list of symbols to not export by using the
3056 @option{--exclude-symbols} option.
3058 @item --no-export-all-symbols
3059 Only export symbols explicitly listed in an input @file{.def} file or in
3060 @samp{.drectve} sections in the input object files. This is the default
3061 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
3062 attributes in the source code.
3064 @item --exclude-symbols @var{list}
3065 Do not export the symbols in @var{list}. This is a list of symbol names
3066 separated by comma or colon characters. The symbol names should not
3067 contain a leading underscore. This is only meaningful when
3068 @option{--export-all-symbols} is used.
3070 @item --no-default-excludes
3071 When @option{--export-all-symbols} is used, it will by default avoid
3072 exporting certain special symbols. The current list of symbols to avoid
3073 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
3074 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
3075 to go ahead and export these special symbols. This is only meaningful
3076 when @option{--export-all-symbols} is used.
3079 @itemx --as @var{path}
3080 Specifies the path, including the filename, of the assembler to be used
3081 to create the exports file.
3083 @item -f @var{options}
3084 @itemx --as-flags @var{options}
3085 Specifies any specific command line options to be passed to the
3086 assembler when building the exports file. This option will work even if
3087 the @option{-S} option is not used. This option only takes one argument,
3088 and if it occurs more than once on the command line, then later
3089 occurrences will override earlier occurrences. So if it is necessary to
3090 pass multiple options to the assembler they should be enclosed in
3094 @itemx --dll-name @var{name}
3095 Specifies the name to be stored in the @file{.def} file as the name of
3096 the DLL when the @option{-e} option is used. If this option is not
3097 present, then the filename given to the @option{-e} option will be
3098 used as the name of the DLL.
3100 @item -m @var{machine}
3101 @itemx -machine @var{machine}
3102 Specifies the type of machine for which the library file should be
3103 built. @command{dlltool} has a built in default type, depending upon how
3104 it was created, but this option can be used to override that. This is
3105 normally only useful when creating DLLs for an ARM processor, when the
3106 contents of the DLL are actually encode using Thumb instructions.
3109 @itemx --add-indirect
3110 Specifies that when @command{dlltool} is creating the exports file it
3111 should add a section which allows the exported functions to be
3112 referenced without using the import library. Whatever the hell that
3116 @itemx --add-underscore
3117 Specifies that when @command{dlltool} is creating the exports file it
3118 should prepend an underscore to the names of the exported functions.
3122 Specifies that when @command{dlltool} is creating the exports file it
3123 should not append the string @samp{@@ <number>}. These numbers are
3124 called ordinal numbers and they represent another way of accessing the
3125 function in a DLL, other than by name.
3128 @itemx --add-stdcall-alias
3129 Specifies that when @command{dlltool} is creating the exports file it
3130 should add aliases for stdcall symbols without @samp{@@ <number>}
3131 in addition to the symbols with @samp{@@ <number>}.
3134 @itemx --ext-prefix-alias @var{prefix}
3135 Causes @command{dlltool} to create external aliases for all DLL
3136 imports with the specified prefix. The aliases are created for both
3137 external and import symbols with no leading underscore.
3141 Specifies that when @command{dlltool} is creating the exports and library
3142 files it should omit the @code{.idata4} section. This is for compatibility
3143 with certain operating systems.
3147 Specifies that when @command{dlltool} is creating the exports and library
3148 files it should omit the @code{.idata5} section. This is for compatibility
3149 with certain operating systems.
3153 Specifies that @command{dlltool} should mark the objects in the library
3154 file and exports file that it produces as supporting interworking
3155 between ARM and Thumb code.
3159 Makes @command{dlltool} preserve the temporary assembler files it used to
3160 create the exports file. If this option is repeated then dlltool will
3161 also preserve the temporary object files it uses to create the library
3164 @item -t @var{prefix}
3165 @itemx --temp-prefix @var{prefix}
3166 Makes @command{dlltool} use @var{prefix} when constructing the names of
3167 temporary assembler and object files. By default, the temp file prefix
3168 is generated from the pid.
3172 Make dlltool describe what it is doing.
3176 Displays a list of command line options and then exits.
3180 Displays dlltool's version number and then exits.
3187 * def file format:: The format of the dlltool @file{.def} file
3190 @node def file format
3191 @section The format of the @command{dlltool} @file{.def} file
3193 A @file{.def} file contains any number of the following commands:
3197 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
3198 The result is going to be named @var{name}@code{.exe}.
3200 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
3201 The result is going to be named @var{name}@code{.dll}.
3203 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) )}
3204 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
3205 Declares @var{name1} as an exported symbol from the DLL, with optional
3206 ordinal number @var{integer}, or declares @var{name1} as an alias
3207 (forward) of the function @var{external-name} in the DLL
3210 @item @code{IMPORTS ( (} @var{internal-name} @code{=} @var{module-name} @code{.} @var{integer} @code{) | [} @var{internal-name} @code{= ]} @var{module-name} @code{.} @var{external-name} @code{) ) *}
3211 Declares that @var{external-name} or the exported function whose
3212 ordinal number is @var{integer} is to be imported from the file
3213 @var{module-name}. If @var{internal-name} is specified then this is
3214 the name that the imported function will be referred to in the body of
3217 @item @code{DESCRIPTION} @var{string}
3218 Puts @var{string} into the output @file{.exp} file in the
3219 @code{.rdata} section.
3221 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
3222 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
3223 Generates @code{--stack} or @code{--heap}
3224 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
3225 section. The linker will see this and act upon it.
3227 @item @code{CODE} @var{attr} @code{+}
3228 @item @code{DATA} @var{attr} @code{+}
3229 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
3230 Generates @code{--attr} @var{section-name} @var{attr} in the output
3231 @code{.drectve} section, where @var{attr} is one of @code{READ},
3232 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
3233 this and act upon it.
3238 @c man begin SEEALSO dlltool
3239 The Info pages for @file{binutils}.
3246 @cindex ELF file information
3249 @c man title readelf Displays information about ELF files.
3252 @c man begin SYNOPSIS readelf
3253 readelf [@option{-a}|@option{--all}]
3254 [@option{-h}|@option{--file-header}]
3255 [@option{-l}|@option{--program-headers}|@option{--segments}]
3256 [@option{-S}|@option{--section-headers}|@option{--sections}]
3257 [@option{-g}|@option{--section-groups}]
3258 [@option{-t}|@option{--section-details}]
3259 [@option{-e}|@option{--headers}]
3260 [@option{-s}|@option{--syms}|@option{--symbols}]
3261 [@option{-n}|@option{--notes}]
3262 [@option{-r}|@option{--relocs}]
3263 [@option{-u}|@option{--unwind}]
3264 [@option{-d}|@option{--dynamic}]
3265 [@option{-V}|@option{--version-info}]
3266 [@option{-A}|@option{--arch-specific}]
3267 [@option{-D}|@option{--use-dynamic}]
3268 [@option{-x} <number>|@option{--hex-dump=}<number>]
3269 [@option{-w[liaprmfFsoR]}|
3270 @option{--debug-dump}[=line,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges]]
3271 [@option{-I}|@option{-histogram}]
3272 [@option{-v}|@option{--version}]
3273 [@option{-W}|@option{--wide}]
3274 [@option{-H}|@option{--help}]
3275 @var{elffile}@dots{}
3279 @c man begin DESCRIPTION readelf
3281 @command{readelf} displays information about one or more ELF format object
3282 files. The options control what particular information to display.
3284 @var{elffile}@dots{} are the object files to be examined. 32-bit and
3285 64-bit ELF files are supported, as are archives containing ELF files.
3287 This program performs a similar function to @command{objdump} but it
3288 goes into more detail and it exists independently of the @sc{bfd}
3289 library, so if there is a bug in @sc{bfd} then readelf will not be
3294 @c man begin OPTIONS readelf
3296 The long and short forms of options, shown here as alternatives, are
3297 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
3303 Equivalent to specifiying @option{--file-header},
3304 @option{--program-headers}, @option{--sections}, @option{--symbols},
3305 @option{--relocs}, @option{--dynamic}, @option{--notes} and
3306 @option{--version-info}.
3309 @itemx --file-header
3310 @cindex ELF file header information
3311 Displays the information contained in the ELF header at the start of the
3315 @itemx --program-headers
3317 @cindex ELF program header information
3318 @cindex ELF segment information
3319 Displays the information contained in the file's segment headers, if it
3324 @itemx --section-headers
3325 @cindex ELF section information
3326 Displays the information contained in the file's section headers, if it
3330 @itemx --section-groups
3331 @cindex ELF section group information
3332 Displays the information contained in the file's section groups, if it
3336 @itemx --section-details
3337 @cindex ELF section information
3338 Displays the detailed section information. Implies @option{-S}.
3343 @cindex ELF symbol table information
3344 Displays the entries in symbol table section of the file, if it has one.
3348 Display all the headers in the file. Equivalent to @option{-h -l -S}.
3353 Displays the contents of the NOTE segments and/or sections, if any.
3357 @cindex ELF reloc information
3358 Displays the contents of the file's relocation section, if it has one.
3362 @cindex unwind information
3363 Displays the contents of the file's unwind section, if it has one. Only
3364 the unwind sections for IA64 ELF files are currently supported.
3368 @cindex ELF dynamic section information
3369 Displays the contents of the file's dynamic section, if it has one.
3372 @itemx --version-info
3373 @cindex ELF version sections informations
3374 Displays the contents of the version sections in the file, it they
3378 @itemx --arch-specific
3379 Displays architecture-specific information in the file, if there
3383 @itemx --use-dynamic
3384 When displaying symbols, this option makes @command{readelf} use the
3385 symbol table in the file's dynamic section, rather than the one in the
3389 @itemx --hex-dump=<number>
3390 Displays the contents of the indicated section as a hexadecimal dump.
3392 @item -w[liaprmfFsoR]
3393 @itemx --debug-dump[=line,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges]
3394 Displays the contents of the debug sections in the file, if any are
3395 present. If one of the optional letters or words follows the switch
3396 then only data found in those specific sections will be dumped.
3400 Display a histogram of bucket list lengths when displaying the contents
3401 of the symbol tables.
3405 Display the version number of readelf.
3409 Don't break output lines to fit into 80 columns. By default
3410 @command{readelf} breaks section header and segment listing lines for
3411 64-bit ELF files, so that they fit into 80 columns. This option causes
3412 @command{readelf} to print each section header resp. each segment one a
3413 single line, which is far more readable on terminals wider than 80 columns.
3417 Display the command line options understood by @command{readelf}.
3424 @c man begin SEEALSO readelf
3425 objdump(1), and the Info entries for @file{binutils}.
3429 @node Selecting The Target System
3430 @chapter Selecting the Target System
3432 You can specify two aspects of the target system to the @sc{gnu}
3433 binary file utilities, each in several ways:
3443 In the following summaries, the lists of ways to specify values are in
3444 order of decreasing precedence. The ways listed first override those
3447 The commands to list valid values only list the values for which the
3448 programs you are running were configured. If they were configured with
3449 @option{--enable-targets=all}, the commands list most of the available
3450 values, but a few are left out; not all targets can be configured in at
3451 once because some of them can only be configured @dfn{native} (on hosts
3452 with the same type as the target system).
3455 * Target Selection::
3456 * Architecture Selection::
3459 @node Target Selection
3460 @section Target Selection
3462 A @dfn{target} is an object file format. A given target may be
3463 supported for multiple architectures (@pxref{Architecture Selection}).
3464 A target selection may also have variations for different operating
3465 systems or architectures.
3467 The command to list valid target values is @samp{objdump -i}
3468 (the first column of output contains the relevant information).
3470 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
3471 @samp{a.out-sunos-big}.
3473 You can also specify a target using a configuration triplet. This is
3474 the same sort of name that is passed to @file{configure} to specify a
3475 target. When you use a configuration triplet as an argument, it must be
3476 fully canonicalized. You can see the canonical version of a triplet by
3477 running the shell script @file{config.sub} which is included with the
3480 Some sample configuration triplets are: @samp{m68k-hp-bsd},
3481 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
3483 @subheading @command{objdump} Target
3489 command line option: @option{-b} or @option{--target}
3492 environment variable @code{GNUTARGET}
3495 deduced from the input file
3498 @subheading @command{objcopy} and @command{strip} Input Target
3504 command line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
3507 environment variable @code{GNUTARGET}
3510 deduced from the input file
3513 @subheading @command{objcopy} and @command{strip} Output Target
3519 command line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
3522 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
3525 environment variable @code{GNUTARGET}
3528 deduced from the input file
3531 @subheading @command{nm}, @command{size}, and @command{strings} Target
3537 command line option: @option{--target}
3540 environment variable @code{GNUTARGET}
3543 deduced from the input file
3546 @node Architecture Selection
3547 @section Architecture Selection
3549 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
3550 to run. Its name may contain a colon, separating the name of the
3551 processor family from the name of the particular @sc{cpu}.
3553 The command to list valid architecture values is @samp{objdump -i} (the
3554 second column contains the relevant information).
3556 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
3558 @subheading @command{objdump} Architecture
3564 command line option: @option{-m} or @option{--architecture}
3567 deduced from the input file
3570 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
3576 deduced from the input file
3579 @node Reporting Bugs
3580 @chapter Reporting Bugs
3582 @cindex reporting bugs
3584 Your bug reports play an essential role in making the binary utilities
3587 Reporting a bug may help you by bringing a solution to your problem, or
3588 it may not. But in any case the principal function of a bug report is
3589 to help the entire community by making the next version of the binary
3590 utilities work better. Bug reports are your contribution to their
3593 In order for a bug report to serve its purpose, you must include the
3594 information that enables us to fix the bug.
3597 * Bug Criteria:: Have you found a bug?
3598 * Bug Reporting:: How to report bugs
3602 @section Have You Found a Bug?
3603 @cindex bug criteria
3605 If you are not sure whether you have found a bug, here are some guidelines:
3608 @cindex fatal signal
3611 If a binary utility gets a fatal signal, for any input whatever, that is
3612 a bug. Reliable utilities never crash.
3614 @cindex error on valid input
3616 If a binary utility produces an error message for valid input, that is a
3620 If you are an experienced user of binary utilities, your suggestions for
3621 improvement are welcome in any case.
3625 @section How to Report Bugs
3627 @cindex bugs, reporting
3629 A number of companies and individuals offer support for @sc{gnu}
3630 products. If you obtained the binary utilities from a support
3631 organization, we recommend you contact that organization first.
3633 You can find contact information for many support companies and
3634 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
3637 In any event, we also recommend that you send bug reports for the binary
3638 utilities to @samp{bug-binutils@@gnu.org}.
3640 The fundamental principle of reporting bugs usefully is this:
3641 @strong{report all the facts}. If you are not sure whether to state a
3642 fact or leave it out, state it!
3644 Often people omit facts because they think they know what causes the
3645 problem and assume that some details do not matter. Thus, you might
3646 assume that the name of a file you use in an example does not matter.
3647 Well, probably it does not, but one cannot be sure. Perhaps the bug is
3648 a stray memory reference which happens to fetch from the location where
3649 that pathname is stored in memory; perhaps, if the pathname were
3650 different, the contents of that location would fool the utility into
3651 doing the right thing despite the bug. Play it safe and give a
3652 specific, complete example. That is the easiest thing for you to do,
3653 and the most helpful.
3655 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
3656 it is new to us. Therefore, always write your bug reports on the assumption
3657 that the bug has not been reported previously.
3659 Sometimes people give a few sketchy facts and ask, ``Does this ring a
3660 bell?'' This cannot help us fix a bug, so it is basically useless. We
3661 respond by asking for enough details to enable us to investigate.
3662 You might as well expedite matters by sending them to begin with.
3664 To enable us to fix the bug, you should include all these things:
3668 The version of the utility. Each utility announces it if you start it
3669 with the @option{--version} argument.
3671 Without this, we will not know whether there is any point in looking for
3672 the bug in the current version of the binary utilities.
3675 Any patches you may have applied to the source, including any patches
3676 made to the @code{BFD} library.
3679 The type of machine you are using, and the operating system name and
3683 What compiler (and its version) was used to compile the utilities---e.g.
3687 The command arguments you gave the utility to observe the bug. To
3688 guarantee you will not omit something important, list them all. A copy
3689 of the Makefile (or the output from make) is sufficient.
3691 If we were to try to guess the arguments, we would probably guess wrong
3692 and then we might not encounter the bug.
3695 A complete input file, or set of input files, that will reproduce the
3696 bug. If the utility is reading an object file or files, then it is
3697 generally most helpful to send the actual object files, uuencoded if
3698 necessary to get them through the mail system. Note that
3699 @samp{bug-binutils@@gnu.org} is a mailing list, so you should avoid
3700 sending very large files to it. Making the files available for
3701 anonymous FTP is OK.
3703 If the source files were produced exclusively using @sc{gnu} programs
3704 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
3705 may be OK to send the source files rather than the object files. In
3706 this case, be sure to say exactly what version of @command{gcc}, or
3707 whatever, was used to produce the object files. Also say how
3708 @command{gcc}, or whatever, was configured.
3711 A description of what behavior you observe that you believe is
3712 incorrect. For example, ``It gets a fatal signal.''
3714 Of course, if the bug is that the utility gets a fatal signal, then we
3715 will certainly notice it. But if the bug is incorrect output, we might
3716 not notice unless it is glaringly wrong. You might as well not give us
3717 a chance to make a mistake.
3719 Even if the problem you experience is a fatal signal, you should still
3720 say so explicitly. Suppose something strange is going on, such as your
3721 copy of the utility is out of synch, or you have encountered a bug in
3722 the C library on your system. (This has happened!) Your copy might
3723 crash and ours would not. If you told us to expect a crash, then when
3724 ours fails to crash, we would know that the bug was not happening for
3725 us. If you had not told us to expect a crash, then we would not be able
3726 to draw any conclusion from our observations.
3729 If you wish to suggest changes to the source, send us context diffs, as
3730 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
3731 option. Always send diffs from the old file to the new file. If you
3732 wish to discuss something in the @command{ld} source, refer to it by
3733 context, not by line number.
3735 The line numbers in our development sources will not match those in your
3736 sources. Your line numbers would convey no useful information to us.
3739 Here are some things that are not necessary:
3743 A description of the envelope of the bug.
3745 Often people who encounter a bug spend a lot of time investigating
3746 which changes to the input file will make the bug go away and which
3747 changes will not affect it.
3749 This is often time consuming and not very useful, because the way we
3750 will find the bug is by running a single example under the debugger
3751 with breakpoints, not by pure deduction from a series of examples.
3752 We recommend that you save your time for something else.
3754 Of course, if you can find a simpler example to report @emph{instead}
3755 of the original one, that is a convenience for us. Errors in the
3756 output will be easier to spot, running under the debugger will take
3757 less time, and so on.
3759 However, simplification is not vital; if you do not want to do this,
3760 report the bug anyway and send us the entire test case you used.
3763 A patch for the bug.
3765 A patch for the bug does help us if it is a good one. But do not omit
3766 the necessary information, such as the test case, on the assumption that
3767 a patch is all we need. We might see problems with your patch and decide
3768 to fix the problem another way, or we might not understand it at all.
3770 Sometimes with programs as complicated as the binary utilities it is
3771 very hard to construct an example that will make the program follow a
3772 certain path through the code. If you do not send us the example, we
3773 will not be able to construct one, so we will not be able to verify that
3776 And if we cannot understand what bug you are trying to fix, or why your
3777 patch should be an improvement, we will not install it. A test case will
3778 help us to understand.
3781 A guess about what the bug is or what it depends on.
3783 Such guesses are usually wrong. Even we cannot guess right about such
3784 things without first using the debugger to find the facts.