Documentation / git-rev-parse.txton commit gitweb: provide a way to customize html headers (c1355b7)
   1git-rev-parse(1)
   2================
   3
   4NAME
   5----
   6git-rev-parse - Pick out and massage parameters
   7
   8
   9SYNOPSIS
  10--------
  11[verse]
  12'git rev-parse' [ --option ] <args>...
  13
  14DESCRIPTION
  15-----------
  16
  17Many git porcelainish commands take mixture of flags
  18(i.e. parameters that begin with a dash '-') and parameters
  19meant for the underlying 'git rev-list' command they use internally
  20and flags and parameters for the other commands they use
  21downstream of 'git rev-list'.  This command is used to
  22distinguish between them.
  23
  24
  25OPTIONS
  26-------
  27--parseopt::
  28        Use 'git rev-parse' in option parsing mode (see PARSEOPT section below).
  29
  30--keep-dashdash::
  31        Only meaningful in `--parseopt` mode. Tells the option parser to echo
  32        out the first `--` met instead of skipping it.
  33
  34--stop-at-non-option::
  35        Only meaningful in `--parseopt` mode.  Lets the option parser stop at
  36        the first non-option argument.  This can be used to parse sub-commands
  37        that take options themselves.
  38
  39--sq-quote::
  40        Use 'git rev-parse' in shell quoting mode (see SQ-QUOTE
  41        section below). In contrast to the `--sq` option below, this
  42        mode does only quoting. Nothing else is done to command input.
  43
  44--revs-only::
  45        Do not output flags and parameters not meant for
  46        'git rev-list' command.
  47
  48--no-revs::
  49        Do not output flags and parameters meant for
  50        'git rev-list' command.
  51
  52--flags::
  53        Do not output non-flag parameters.
  54
  55--no-flags::
  56        Do not output flag parameters.
  57
  58--default <arg>::
  59        If there is no parameter given by the user, use `<arg>`
  60        instead.
  61
  62--verify::
  63        The parameter given must be usable as a single, valid
  64        object name.  Otherwise barf and abort.
  65
  66-q::
  67--quiet::
  68        Only meaningful in `--verify` mode. Do not output an error
  69        message if the first argument is not a valid object name;
  70        instead exit with non-zero status silently.
  71
  72--sq::
  73        Usually the output is made one line per flag and
  74        parameter.  This option makes output a single line,
  75        properly quoted for consumption by shell.  Useful when
  76        you expect your parameter to contain whitespaces and
  77        newlines (e.g. when using pickaxe `-S` with
  78        'git diff-{asterisk}'). In contrast to the `--sq-quote` option,
  79        the command input is still interpreted as usual.
  80
  81--not::
  82        When showing object names, prefix them with '{caret}' and
  83        strip '{caret}' prefix from the object names that already have
  84        one.
  85
  86--symbolic::
  87        Usually the object names are output in SHA1 form (with
  88        possible '{caret}' prefix); this option makes them output in a
  89        form as close to the original input as possible.
  90
  91--symbolic-full-name::
  92        This is similar to \--symbolic, but it omits input that
  93        are not refs (i.e. branch or tag names; or more
  94        explicitly disambiguating "heads/master" form, when you
  95        want to name the "master" branch when there is an
  96        unfortunately named tag "master"), and show them as full
  97        refnames (e.g. "refs/heads/master").
  98
  99--abbrev-ref[=(strict|loose)]::
 100        A non-ambiguous short name of the objects name.
 101        The option core.warnAmbiguousRefs is used to select the strict
 102        abbreviation mode.
 103
 104--all::
 105        Show all refs found in `refs/`.
 106
 107--branches[=pattern]::
 108--tags[=pattern]::
 109--remotes[=pattern]::
 110        Show all branches, tags, or remote-tracking branches,
 111        respectively (i.e., refs found in `refs/heads`,
 112        `refs/tags`, or `refs/remotes`, respectively).
 113+
 114If a `pattern` is given, only refs matching the given shell glob are
 115shown.  If the pattern does not contain a globbing character (`?`,
 116`{asterisk}`, or `[`), it is turned into a prefix match by
 117appending `/{asterisk}`.
 118
 119--glob=pattern::
 120        Show all refs matching the shell glob pattern `pattern`. If
 121        the pattern does not start with `refs/`, this is automatically
 122        prepended.  If the pattern does not contain a globbing
 123        character (`?`, `{asterisk}`, or `[`), it is turned into a prefix
 124        match by appending `/{asterisk}`.
 125
 126--show-toplevel::
 127        Show the absolute path of the top-level directory.
 128
 129--show-prefix::
 130        When the command is invoked from a subdirectory, show the
 131        path of the current directory relative to the top-level
 132        directory.
 133
 134--show-cdup::
 135        When the command is invoked from a subdirectory, show the
 136        path of the top-level directory relative to the current
 137        directory (typically a sequence of "../", or an empty string).
 138
 139--git-dir::
 140        Show `$GIT_DIR` if defined. Otherwise show the path to
 141        the .git directory, relative to the current directory.
 142+
 143If `$GIT_DIR` is not defined and the current directory
 144is not detected to lie in a git repository or work tree
 145print a message to stderr and exit with nonzero status.
 146
 147--is-inside-git-dir::
 148        When the current working directory is below the repository
 149        directory print "true", otherwise "false".
 150
 151--is-inside-work-tree::
 152        When the current working directory is inside the work tree of the
 153        repository print "true", otherwise "false".
 154
 155--is-bare-repository::
 156        When the repository is bare print "true", otherwise "false".
 157
 158--local-env-vars::
 159        List the GIT_* environment variables that are local to the
 160        repository (e.g. GIT_DIR or GIT_WORK_TREE, but not GIT_EDITOR).
 161        Only the names of the variables are listed, not their value,
 162        even if they are set.
 163
 164--short::
 165--short=number::
 166        Instead of outputting the full SHA1 values of object names try to
 167        abbreviate them to a shorter unique name. When no length is specified
 168        7 is used. The minimum length is 4.
 169
 170--since=datestring::
 171--after=datestring::
 172        Parse the date string, and output the corresponding
 173        --max-age= parameter for 'git rev-list'.
 174
 175--until=datestring::
 176--before=datestring::
 177        Parse the date string, and output the corresponding
 178        --min-age= parameter for 'git rev-list'.
 179
 180<args>...::
 181        Flags and parameters to be parsed.
 182
 183
 184include::revisions.txt[]
 185
 186PARSEOPT
 187--------
 188
 189In `--parseopt` mode, 'git rev-parse' helps massaging options to bring to shell
 190scripts the same facilities C builtins have. It works as an option normalizer
 191(e.g. splits single switches aggregate values), a bit like `getopt(1)` does.
 192
 193It takes on the standard input the specification of the options to parse and
 194understand, and echoes on the standard output a string suitable for `sh(1)` `eval`
 195to replace the arguments with normalized ones.  In case of error, it outputs
 196usage on the standard error stream, and exits with code 129.
 197
 198Note: Make sure you quote the result when passing it to `eval`.  See
 199below for an example.
 200
 201Input Format
 202~~~~~~~~~~~~
 203
 204'git rev-parse --parseopt' input format is fully text based. It has two parts,
 205separated by a line that contains only `--`. The lines before the separator
 206(should be more than one) are used for the usage.
 207The lines after the separator describe the options.
 208
 209Each line of options has this format:
 210
 211------------
 212<opt_spec><flags>* SP+ help LF
 213------------
 214
 215`<opt_spec>`::
 216        its format is the short option character, then the long option name
 217        separated by a comma. Both parts are not required, though at least one
 218        is necessary. `h,help`, `dry-run` and `f` are all three correct
 219        `<opt_spec>`.
 220
 221`<flags>`::
 222        `<flags>` are of `*`, `=`, `?` or `!`.
 223        * Use `=` if the option takes an argument.
 224
 225        * Use `?` to mean that the option is optional (though its use is discouraged).
 226
 227        * Use `*` to mean that this option should not be listed in the usage
 228          generated for the `-h` argument. It's shown for `--help-all` as
 229          documented in linkgit:gitcli[7].
 230
 231        * Use `!` to not make the corresponding negated long option available.
 232
 233The remainder of the line, after stripping the spaces, is used
 234as the help associated to the option.
 235
 236Blank lines are ignored, and lines that don't match this specification are used
 237as option group headers (start the line with a space to create such
 238lines on purpose).
 239
 240Example
 241~~~~~~~
 242
 243------------
 244OPTS_SPEC="\
 245some-command [options] <args>...
 246
 247some-command does foo and bar!
 248--
 249h,help    show the help
 250
 251foo       some nifty option --foo
 252bar=      some cool option --bar with an argument
 253
 254  An option group Header
 255C?        option C with an optional argument"
 256
 257eval "$(echo "$OPTS_SPEC" | git rev-parse --parseopt -- "$@" || echo exit $?)"
 258------------
 259
 260SQ-QUOTE
 261--------
 262
 263In `--sq-quote` mode, 'git rev-parse' echoes on the standard output a
 264single line suitable for `sh(1)` `eval`. This line is made by
 265normalizing the arguments following `--sq-quote`. Nothing other than
 266quoting the arguments is done.
 267
 268If you want command input to still be interpreted as usual by
 269'git rev-parse' before the output is shell quoted, see the `--sq`
 270option.
 271
 272Example
 273~~~~~~~
 274
 275------------
 276$ cat >your-git-script.sh <<\EOF
 277#!/bin/sh
 278args=$(git rev-parse --sq-quote "$@")   # quote user-supplied arguments
 279command="git frotz -n24 $args"          # and use it inside a handcrafted
 280                                        # command line
 281eval "$command"
 282EOF
 283
 284$ sh your-git-script.sh "a b'c"
 285------------
 286
 287EXAMPLES
 288--------
 289
 290* Print the object name of the current commit:
 291+
 292------------
 293$ git rev-parse --verify HEAD
 294------------
 295
 296* Print the commit object name from the revision in the $REV shell variable:
 297+
 298------------
 299$ git rev-parse --verify $REV
 300------------
 301+
 302This will error out if $REV is empty or not a valid revision.
 303
 304* Same as above:
 305+
 306------------
 307$ git rev-parse --default master --verify $REV
 308------------
 309+
 310but if $REV is empty, the commit object name from master will be printed.
 311
 312GIT
 313---
 314Part of the linkgit:git[1] suite