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
deleted.
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 end.
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 replaced.
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 included.
If you do not specify a member, all files in the archive are
listed.
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
extracted.
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 directory.
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 Specify dependencies of this library. The dependencies must
immediately follow this option character, must use the same
syntax as the linker command line, and must be specified
within a single argument. I.e., if multiple items are
needed, they must be quoted to form a single command line
argument. For example L "-L/usr/local/lib -lmydep1 -lmydep2"
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 option.
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 replacement.
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
--enable-deterministic-archives.
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:
--help
Displays the list of command-line options supported by ar and
then exits.
--version
Displays the version information of ar and then exits.
-X32_64
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 ar.
--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 liblto_plugin.so.0.0.0. For
Clang based compilations it is called LLVMgold.so. 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.
--record-libdeps libdeps
The --record-libdeps option is identical to the l modifier,
just handled in long form.
@file
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 removed.
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.
