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AR(1)			     GNU Development Tools			 AR(1)

       ar - create, modify, and	extract	from archives

       ar [-X32_64] [-]p[mod] [--plugin	name] [--target	bfdname] [--output
       dirname]	[relpos] [count] archive [member...]

       The GNU ar program creates, modifies, and extracts from archives.  An
       archive is a single file	holding	a collection of	other files in a
       structure that makes it possible	to retrieve the	original individual
       files (called members of	the archive).

       The original files' contents, mode (permissions), timestamp, owner, and
       group are preserved in the archive, and can be restored on extraction.

       GNU ar can maintain archives whose members have names of	any length;
       however,	depending on how ar is configured on your system, a limit on
       member-name length may be imposed for compatibility with	archive
       formats maintained with other tools.  If	it exists, the limit is	often
       15 characters (typical of formats related to a.out) or 16 characters
       (typical	of formats related to coff).

       ar is considered	a binary utility because archives of this sort are
       most often used as libraries holding commonly needed subroutines.

       ar creates an index to the symbols defined in relocatable object
       modules in the archive when you specify the modifier s.	Once created,
       this index is updated in	the archive whenever ar	makes a	change to its
       contents	(save for the q	update operation).  An archive with such an
       index speeds up linking to the library, and allows routines in the
       library to call each other without regard to their placement in the

       You may use nm -s or nm --print-armap to	list this index	table.	If an
       archive lacks the table,	another	form of	ar called ranlib can be	used
       to add just the table.

       GNU ar can optionally create a thin archive, which contains a symbol
       index and references to the original copies of the member files of the
       archive.	 This is useful	for building libraries for use within a	local
       build tree, where the relocatable objects are expected to remain
       available, and copying the contents of each object would	only waste
       time and	space.

       An archive can either be	thin or	it can be normal.  It cannot be	both
       at the same time.  Once an archive is created its format	cannot be
       changed without first deleting it and then creating a new archive in
       its place.

       Thin archives are also flattened, so that adding	one thin archive to
       another thin archive does not nest it, as would happen with a normal
       archive.	 Instead the elements of the first archive are added
       individually to the second archive.

       The paths to the	elements of the	archive	are stored relative to the
       archive itself.

       GNU ar is designed to be	compatible with	two different facilities.  You
       can control its activity	using command-line options, like the different
       varieties of ar on Unix systems;	or, if you specify the single command-
       line option -M, you can control it with a script	supplied via standard
       input, like the MRI "librarian" program.

       GNU ar allows you to mix	the operation code p and modifier flags	mod in
       any order, within the first command-line	argument.

       If you wish, you	may begin the first command-line argument with a dash.

       The p keyletter specifies what operation	to execute; it may be any of
       the following, but you must specify only	one of them:

       d   Delete modules from the archive.  Specify the names of modules to
	   be deleted as member...; the	archive	is untouched if	you specify no
	   files to delete.

	   If you specify the v	modifier, ar lists each	module as it is

       m   Use this operation to move members in an archive.

	   The ordering	of members in an archive can make a difference in how
	   programs are	linked using the library, if a symbol is defined in
	   more	than one member.

	   If no modifiers are used with "m", any members you name in the
	   member arguments are	moved to the end of the	archive; you can use
	   the a, b, or	i modifiers to move them to a specified	place instead.

       p   Print the specified members of the archive, to the standard output
	   file.  If the v modifier is specified, show the member name before
	   copying its contents	to standard output.

	   If you specify no member arguments, all the files in	the archive
	   are printed.

       q   Quick append; Historically, add the files member... to the end of
	   archive, without checking for replacement.

	   The modifiers a, b, and i do	not affect this	operation; new members
	   are always placed at	the end	of the archive.

	   The modifier	v makes	ar list	each file as it	is appended.

	   Since the point of this operation is	speed, implementations of ar
	   have	the option of not updating the archive's symbol	table if one
	   exists.  Too	many different systems however assume that symbol
	   tables are always up-to-date, so GNU	ar will	rebuild	the table even
	   with	a quick	append.

	   Note	- GNU ar treats	the command qs as a synonym for	r - replacing
	   already existing files in the archive and appending new ones	at the

       r   Insert the files member... into archive (with replacement). This
	   operation differs from q in that any	previously existing members
	   are deleted if their	names match those being	added.

	   If one of the files named in	member... does not exist, ar displays
	   an error message, and leaves	undisturbed any	existing members of
	   the archive matching	that name.

	   By default, new members are added at	the end	of the file; but you
	   may use one of the modifiers	a, b, or i to request placement
	   relative to some existing member.

	   The modifier	v used with this operation elicits a line of output
	   for each file inserted, along with one of the letters a or r	to
	   indicate whether the	file was appended (no old member deleted) or

       s   Add an index	to the archive,	or update it if	it already exists.
	   Note	this command is	an exception to	the rule that there can	only
	   be one command letter, as it	is possible to use it as either	a
	   command or a	modifier.  In either case it does the same thing.

       t   Display a table listing the contents	of archive, or those of	the
	   files listed	in member... that are present in the archive.
	   Normally only the member name is shown, but if the modifier O is
	   specified, then the corresponding offset of the member is also
	   displayed.  Finally,	in order to see	the modes (permissions),
	   timestamp, owner, group, and	size the v modifier should be

	   If you do not specify a member, all files in	the archive are

	   If there is more than one file with the same	name (say, fie)	in an
	   archive (say	b.a), ar t b.a fie lists only the first	instance; to
	   see them all, you must ask for a complete listing---in our example,
	   ar t	b.a.

       x   Extract members (named member) from the archive.  You can use the v
	   modifier with this operation, to request that ar list each name as
	   it extracts it.

	   If you do not specify a member, all files in	the archive are

	   Files cannot	be extracted from a thin archive, and there are
	   restrictions	on extracting from archives created with P: The	paths
	   must	not be absolute, may not contain "..", and any subdirectories
	   in the paths	must exist.  If	it is desired to avoid these
	   restrictions	then used the --output option to specify an output

       A number	of modifiers (mod) may immediately follow the p	keyletter, to
       specify variations on an	operation's behavior:

       a   Add new files after an existing member of the archive.  If you use
	   the modifier	a, the name of an existing archive member must be
	   present as the relpos argument, before the archive specification.

       b   Add new files before	an existing member of the archive.  If you use
	   the modifier	b, the name of an existing archive member must be
	   present as the relpos argument, before the archive specification.
	   (same as i).

       c   Create the archive.	The specified archive is always	created	if it
	   did not exist, when you request an update.  But a warning is	issued
	   unless you specify in advance that you expect to create it, by
	   using this modifier.

       D   Operate in deterministic mode.  When	adding files and the archive
	   index use zero for UIDs, GIDs, timestamps, and use consistent file
	   modes for all files.	 When this option is used, if ar is used with
	   identical options and identical input files,	multiple runs will
	   create identical output files regardless of the input files'
	   owners, groups, file	modes, or modification times.

	   If binutils was configured with --enable-deterministic-archives,
	   then	this mode is on	by default.  It	can be disabled	with the U
	   modifier, below.

       f   Truncate names in the archive.  GNU ar will normally	permit file
	   names of any	length.	 This will cause it to create archives which
	   are not compatible with the native ar program on some systems.  If
	   this	is a concern, the f modifier may be used to truncate file
	   names when putting them in the archive.

       i   Insert new files before an existing member of the archive.  If you
	   use the modifier i, the name	of an existing archive member must be
	   present as the relpos argument, before the archive specification.
	   (same as b).

       l   This	modifier is accepted but not used.

       N   Uses	the count parameter.  This is used if there are	multiple
	   entries in the archive with the same	name.  Extract or delete
	   instance count of the given name from the archive.

       o   Preserve the	original dates of members when extracting them.	 If
	   you do not specify this modifier, files extracted from the archive
	   are stamped with the	time of	extraction.

       O   Display member offsets inside the archive. Use together with	the t

       P   Use the full	path name when matching	or storing names in the
	   archive.  Archives created with full	path names are not POSIX
	   compliant, and thus may not work with tools other than up to	date
	   GNU tools.  Modifying such archives with GNU	ar without using P
	   will	remove the full	path names unless the archive is a thin
	   archive.  Note that P may be	useful when adding files to a thin
	   archive since r without P ignores the path when choosing which
	   element to replace.	Thus

		   ar rcST archive.a subdir/file1 subdir/file2 file1

	   will	result in the first "subdir/file1" being replaced with "file1"
	   from	the current directory.	Adding P will prevent this

       s   Write an object-file	index into the archive,	or update an existing
	   one,	even if	no other change	is made	to the archive.	 You may use
	   this	modifier flag either with any operation, or alone.  Running ar
	   s on	an archive is equivalent to running ranlib on it.

       S   Do not generate an archive symbol table.  This can speed up
	   building a large library in several steps.  The resulting archive
	   can not be used with	the linker.  In	order to build a symbol	table,
	   you must omit the S modifier	on the last execution of ar, or	you
	   must	run ranlib on the archive.

       T   Make	the specified archive a	thin archive.  If it already exists
	   and is a regular archive, the existing members must be present in
	   the same directory as archive.

       u   Normally, ar	r... inserts all files listed into the archive.	 If
	   you would like to insert only those of the files you	list that are
	   newer than existing members of the same names, use this modifier.
	   The u modifier is allowed only for the operation r (replace).  In
	   particular, the combination qu is not allowed, since	checking the
	   timestamps would lose any speed advantage from the operation	q.

       U   Do not operate in deterministic mode.  This is the inverse of the D
	   modifier, above: added files	and the	archive	index will get their
	   actual UID, GID, timestamp, and file	mode values.

	   This	is the default unless binutils was configured with

       v   This	modifier requests the verbose version of an operation.	Many
	   operations display additional information, such as filenames
	   processed, when the modifier	v is appended.

       V   This	modifier shows the version number of ar.

       The ar program also supports some command-line options which are
       neither modifiers nor actions, but which	do change its behaviour	in
       specific	ways:

	   Displays the	list of	command-line options supported by ar and then

	   Displays the	version	information of ar and then exits.

	   ar ignores an initial option	spelled	-X32_64, for compatibility
	   with	AIX.  The behaviour produced by	this option is the default for
	   GNU ar.  ar does not	support	any of the other -X options; in
	   particular, it does not support -X32	which is the default for AIX

       --plugin	name
	   The optional	command-line switch --plugin name causes ar to load
	   the plugin called name which	adds support for more file formats,
	   including object files with link-time optimization information.

	   This	option is only available if the	toolchain has been built with
	   plugin support enabled.

	   If --plugin is not provided,	but plugin support has been enabled
	   then	ar iterates over the files in ${libdir}/bfd-plugins in
	   alphabetic order and	the first plugin that claims the object	in
	   question is used.

	   Please note that this plugin	search directory is not	the one	used
	   by ld's -plugin option.  In order to	make ar	use the	 linker	plugin
	   it must be copied into the ${libdir}/bfd-plugins directory.	For
	   GCC based compilations the linker plugin is called  For	Clang based compilations it is called	 The GCC plugin	is always backwards compatible with
	   earlier versions, so	it is sufficient to just copy the newest one.

       --target	target
	   The optional	command-line switch --target bfdname specifies that
	   the archive members are in an object	code format different from
	   your	system's default format.  See

       --output	dirname
	   The --output	option can be used to specify a	path to	a directory
	   into	which archive members should be	extracted.  If this option is
	   not specified then the current directory will be used.

	   Note	- although the presence	of this	option does imply a x
	   extraction operation	that option must still be included on the
	   command line.

	   Read	command-line options from file.	 The options read are inserted
	   in place of the original @file option.  If file does	not exist, or
	   cannot be read, then	the option will	be treated literally, and not

	   Options in file are separated by whitespace.	 A whitespace
	   character may be included in	an option by surrounding the entire
	   option in either single or double quotes.  Any character (including
	   a backslash)	may be included	by prefixing the character to be
	   included with a backslash.  The file	may itself contain additional
	   @file options; any such options will	be processed recursively.

       nm(1), ranlib(1), and the Info entries for binutils.

       Copyright (c) 1991-2020 Free Software Foundation, Inc.

       Permission is granted to	copy, distribute and/or	modify this document
       under the terms of the GNU Free Documentation License, Version 1.3 or
       any later version published by the Free Software	Foundation; with no
       Invariant Sections, with	no Front-Cover Texts, and with no Back-Cover
       Texts.  A copy of the license is	included in the	section	entitled "GNU
       Free Documentation License".

binutils-2.34			  2022-09-06				 AR(1)


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