git-cat-file

GIT-CAT-FILE(1)                   Git Manual                   GIT-CAT-FILE(1)

NAME
       git-cat-file - Provide content or type and size information for
       repository objects

SYNOPSIS
       git cat-file (-t [--allow-unknown-type]| -s [--allow-unknown-type]| -e | -p | <type> | --textconv | --filters ) [--path=<path>] <object>
       git cat-file (--batch | --batch-check) [ --textconv | --filters ] [--follow-symlinks]

DESCRIPTION
       In its first form, the command provides the content or the type of an
       object in the repository. The type is required unless -t or -p is used
       to find the object type, or -s is used to find the object size, or
       --textconv or --filters is used (which imply type "blob").

       In the second form, a list of objects (separated by linefeeds) is
       provided on stdin, and the SHA-1, type, and size of each object is
       printed on stdout. The output format can be overridden using the
       optional <format> argument. If either --textconv or --filters was
       specified, the input is expected to list the object names followed by
       the path name, separated by a single whitespace, so that the
       appropriate drivers can be determined.

OPTIONS
       <object>
           The name of the object to show. For a more complete list of ways to
           spell object names, see the "SPECIFYING REVISIONS" section in
           gitrevisions(7).

       -t
           Instead of the content, show the object type identified by
           <object>.

       -s
           Instead of the content, show the object size identified by
           <object>.

       -e
           Exit with zero status if <object> exists and is a valid object. If
           <object> is of an invalid format exit with non-zero and emits an
           error on stderr.

       -p
           Pretty-print the contents of <object> based on its type.

       <type>
           Typically this matches the real type of <object> but asking for a
           type that can trivially be dereferenced from the given <object> is
           also permitted. An example is to ask for a "tree" with <object>
           being a commit object that contains it, or to ask for a "blob" with
           <object> being a tag object that points at it.

       --textconv
           Show the content as transformed by a textconv filter. In this case,
           <object> has to be of the form <tree-ish>:<path>, or :<path> in
           order to apply the filter to the content recorded in the index at
           <path>.

       --filters
           Show the content as converted by the filters configured in the
           current working tree for the given <path> (i.e. smudge filters,
           end-of-line conversion, etc). In this case, <object> has to be of
           the form <tree-ish>:<path>, or :<path>.

       --path=<path>
           For use with --textconv or --filters, to allow specifying an object
           name and a path separately, e.g. when it is difficult to figure out
           the revision from which the blob came.

       --batch, --batch=<format>
           Print object information and contents for each object provided on
           stdin. May not be combined with any other options or arguments
           except --textconv or --filters, in which case the input lines also
           need to specify the path, separated by whitespace. See the section
           BATCH OUTPUT below for details.

       --batch-check, --batch-check=<format>
           Print object information for each object provided on stdin. May not
           be combined with any other options or arguments except --textconv
           or --filters, in which case the input lines also need to specify
           the path, separated by whitespace. See the section BATCH OUTPUT
           below for details.

       --batch-all-objects
           Instead of reading a list of objects on stdin, perform the
           requested batch operation on all objects in the repository and any
           alternate object stores (not just reachable objects). Requires
           --batch or --batch-check be specified. Note that the objects are
           visited in order sorted by their hashes.

       --buffer
           Normally batch output is flushed after each object is output, so
           that a process can interactively read and write from cat-file. With
           this option, the output uses normal stdio buffering; this is much
           more efficient when invoking --batch-check on a large number of
           objects.

       --unordered
           When --batch-all-objects is in use, visit objects in an order which
           may be more efficient for accessing the object contents than hash
           order. The exact details of the order are unspecified, but if you
           do not require a specific order, this should generally result in
           faster output, especially with --batch. Note that cat-file will
           still show each object only once, even if it is stored multiple
           times in the repository.

       --allow-unknown-type
           Allow -s or -t to query broken/corrupt objects of unknown type.

       --follow-symlinks
           With --batch or --batch-check, follow symlinks inside the
           repository when requesting objects with extended SHA-1 expressions
           of the form tree-ish:path-in-tree. Instead of providing output
           about the link itself, provide output about the linked-to object.
           If a symlink points outside the tree-ish (e.g. a link to /foo or a
           root-level link to ../foo), the portion of the link which is
           outside the tree will be printed.

           This option does not (currently) work correctly when an object in
           the index is specified (e.g.  :link instead of HEAD:link) rather
           than one in the tree.

           This option cannot (currently) be used unless --batch or
           --batch-check is used.

           For example, consider a git repository containing:

               f: a file containing "hello\n"
               link: a symlink to f
               dir/link: a symlink to ../f
               plink: a symlink to ../f
               alink: a symlink to /etc/passwd

           For a regular file f, echo HEAD:f | git cat-file --batch would
           print

               ce013625030ba8dba906f756967f9e9ca394464a blob 6

           And echo HEAD:link | git cat-file --batch --follow-symlinks would
           print the same thing, as would HEAD:dir/link, as they both point at
           HEAD:f.

           Without --follow-symlinks, these would print data about the symlink
           itself. In the case of HEAD:link, you would see

               4d1ae35ba2c8ec712fa2a379db44ad639ca277bd blob 1

           Both plink and alink point outside the tree, so they would
           respectively print:

               symlink 4
               ../f

               symlink 11
               /etc/passwd

OUTPUT
       If -t is specified, one of the <type>.

       If -s is specified, the size of the <object> in bytes.

       If -e is specified, no output, unless the <object> is malformed.

       If -p is specified, the contents of <object> are pretty-printed.

       If <type> is specified, the raw (though uncompressed) contents of the
       <object> will be returned.

BATCH OUTPUT
       If --batch or --batch-check is given, cat-file will read objects from
       stdin, one per line, and print information about them. By default, the
       whole line is considered as an object, as if it were fed to git-rev-
       parse(1).

       You can specify the information shown for each object by using a custom
       <format>. The <format> is copied literally to stdout for each object,
       with placeholders of the form %(atom) expanded, followed by a newline.
       The available atoms are:

       objectname
           The 40-hex object name of the object.

       objecttype
           The type of the object (the same as cat-file -t reports).

       objectsize
           The size, in bytes, of the object (the same as cat-file -s
           reports).

       objectsize:disk
           The size, in bytes, that the object takes up on disk. See the note
           about on-disk sizes in the CAVEATS section below.

       deltabase
           If the object is stored as a delta on-disk, this expands to the
           40-hex sha1 of the delta base object. Otherwise, expands to the
           null sha1 (40 zeroes). See CAVEATS below.

       rest
           If this atom is used in the output string, input lines are split at
           the first whitespace boundary. All characters before that
           whitespace are considered to be the object name; characters after
           that first run of whitespace (i.e., the "rest" of the line) are
           output in place of the %(rest) atom.

       If no format is specified, the default format is %(objectname)
       %(objecttype) %(objectsize).

       If --batch is specified, the object information is followed by the
       object contents (consisting of %(objectsize) bytes), followed by a
       newline.

       For example, --batch without a custom format would produce:

           <sha1> SP <type> SP <size> LF
           <contents> LF

       Whereas --batch-check='%(objectname) %(objecttype)' would produce:

           <sha1> SP <type> LF

       If a name is specified on stdin that cannot be resolved to an object in
       the repository, then cat-file will ignore any custom format and print:

           <object> SP missing LF

       If a name is specified that might refer to more than one object (an
       ambiguous short sha), then cat-file will ignore any custom format and
       print:

           <object> SP ambiguous LF

       If --follow-symlinks is used, and a symlink in the repository points
       outside the repository, then cat-file will ignore any custom format and
       print:

           symlink SP <size> LF
           <symlink> LF

       The symlink will either be absolute (beginning with a /), or relative
       to the tree root. For instance, if dir/link points to ../../foo, then
       <symlink> will be ../foo. <size> is the size of the symlink in bytes.

       If --follow-symlinks is used, the following error messages will be
       displayed:

           <object> SP missing LF

       is printed when the initial symlink requested does not exist.

           dangling SP <size> LF
           <object> LF

       is printed when the initial symlink exists, but something that it
       (transitive-of) points to does not.

           loop SP <size> LF
           <object> LF

       is printed for symlink loops (or any symlinks that require more than 40
       link resolutions to resolve).

           notdir SP <size> LF
           <object> LF

       is printed when, during symlink resolution, a file is used as a
       directory name.

CAVEATS
       Note that the sizes of objects on disk are reported accurately, but
       care should be taken in drawing conclusions about which refs or objects
       are responsible for disk usage. The size of a packed non-delta object
       may be much larger than the size of objects which delta against it, but
       the choice of which object is the base and which is the delta is
       arbitrary and is subject to change during a repack.

       Note also that multiple copies of an object may be present in the
       object database; in this case, it is undefined which copy's size or
       delta base will be reported.

GIT
       Part of the git(1) suite

Git 2.25.1                        04/26/2023                   GIT-CAT-FILE(1)