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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] [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; if you also want to see the
	   modes (permissions), timestamp, owner, group, and size, you can
	   request that by also specifying the v modifier.

	   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.

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

	   Displays the version information of ar and then exits.

       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.

       P   Use the full path name when matching names in the archive.  GNU ar
	   can not create an archive with a full path name (such archives are
	   not POSIX complaint), but other archive creators can.  This option
	   will cause GNU ar to match file names using a complete path name,
	   which can be convenient when extracting a single file from an
	   archive created by another tool.

       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.

       ar ignores an initial option spelt -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 ar.

       The optional command line switch --plugin name causes ar to load the
       plugin called name which adds support for more file formats.  This
       option is only available if the toolchain has been built with plugin
       support enabled.

       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

	   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) 1991-2016 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-2.27			  2016-08-03				 AR(1)