Documentation / git-for-each-ref.txton commit git grep: Add "-z/--null" option as in GNU's grep. (83caecc)
   1git-for-each-ref(1)
   2===================
   3
   4NAME
   5----
   6git-for-each-ref - Output information on each ref
   7
   8SYNOPSIS
   9--------
  10[verse]
  11'git for-each-ref' [--count=<count>] [--shell|--perl|--python|--tcl]
  12                   [--sort=<key>]\* [--format=<format>] [<pattern>...]
  13
  14DESCRIPTION
  15-----------
  16
  17Iterate over all refs that match `<pattern>` and show them
  18according to the given `<format>`, after sorting them according
  19to the given set of `<key>`.  If `<count>` is given, stop after
  20showing that many refs.  The interpolated values in `<format>`
  21can optionally be quoted as string literals in the specified
  22host language allowing their direct evaluation in that language.
  23
  24OPTIONS
  25-------
  26<count>::
  27        By default the command shows all refs that match
  28        `<pattern>`.  This option makes it stop after showing
  29        that many refs.
  30
  31<key>::
  32        A field name to sort on.  Prefix `-` to sort in
  33        descending order of the value.  When unspecified,
  34        `refname` is used.  You may use the --sort=<key> option
  35        multiple times, in which case the last key becomes the primary
  36        key.
  37
  38<format>::
  39        A string that interpolates `%(fieldname)` from the
  40        object pointed at by a ref being shown.  If `fieldname`
  41        is prefixed with an asterisk (`*`) and the ref points
  42        at a tag object, the value for the field in the object
  43        tag refers is used.  When unspecified, defaults to
  44        `%(objectname) SPC %(objecttype) TAB %(refname)`.
  45        It also interpolates `%%` to `%`, and `%xx` where `xx`
  46        are hex digits interpolates to character with hex code
  47        `xx`; for example `%00` interpolates to `\0` (NUL),
  48        `%09` to `\t` (TAB) and `%0a` to `\n` (LF).
  49
  50<pattern>...::
  51        If one or more patterns are given, only refs are shown that
  52        match against at least one pattern, either using fnmatch(3) or
  53        literally, in the latter case matching completely or from the
  54        beginning up to a slash.
  55
  56--shell::
  57--perl::
  58--python::
  59--tcl::
  60        If given, strings that substitute `%(fieldname)`
  61        placeholders are quoted as string literals suitable for
  62        the specified host language.  This is meant to produce
  63        a scriptlet that can directly be `eval`ed.
  64
  65
  66FIELD NAMES
  67-----------
  68
  69Various values from structured fields in referenced objects can
  70be used to interpolate into the resulting output, or as sort
  71keys.
  72
  73For all objects, the following names can be used:
  74
  75refname::
  76        The name of the ref (the part after $GIT_DIR/).
  77        For a non-ambiguous short name of the ref append `:short`.
  78
  79objecttype::
  80        The type of the object (`blob`, `tree`, `commit`, `tag`).
  81
  82objectsize::
  83        The size of the object (the same as 'git-cat-file -s' reports).
  84
  85objectname::
  86        The object name (aka SHA-1).
  87
  88In addition to the above, for commit and tag objects, the header
  89field names (`tree`, `parent`, `object`, `type`, and `tag`) can
  90be used to specify the value in the header field.
  91
  92Fields that have name-email-date tuple as its value (`author`,
  93`committer`, and `tagger`) can be suffixed with `name`, `email`,
  94and `date` to extract the named component.
  95
  96The first line of the message in a commit and tag object is
  97`subject`, the remaining lines are `body`.  The whole message
  98is `contents`.
  99
 100For sorting purposes, fields with numeric values sort in numeric
 101order (`objectsize`, `authordate`, `committerdate`, `taggerdate`).
 102All other fields are used to sort in their byte-value order.
 103
 104In any case, a field name that refers to a field inapplicable to
 105the object referred by the ref does not cause an error.  It
 106returns an empty string instead.
 107
 108As a special case for the date-type fields, you may specify a format for
 109the date by adding one of `:default`, `:relative`, `:short`, `:local`,
 110`:iso8601` or `:rfc2822` to the end of the fieldname; e.g.
 111`%(taggerdate:relative)`.
 112
 113
 114EXAMPLES
 115--------
 116
 117An example directly producing formatted text.  Show the most recent
 1183 tagged commits::
 119
 120------------
 121#!/bin/sh
 122
 123git for-each-ref --count=3 --sort='-*authordate' \
 124--format='From: %(*authorname) %(*authoremail)
 125Subject: %(*subject)
 126Date: %(*authordate)
 127Ref: %(*refname)
 128
 129%(*body)
 130' 'refs/tags'
 131------------
 132
 133
 134A simple example showing the use of shell eval on the output,
 135demonstrating the use of --shell.  List the prefixes of all heads::
 136------------
 137#!/bin/sh
 138
 139git for-each-ref --shell --format="ref=%(refname)" refs/heads | \
 140while read entry
 141do
 142        eval "$entry"
 143        echo `dirname $ref`
 144done
 145------------
 146
 147
 148A bit more elaborate report on tags, demonstrating that the format
 149may be an entire script::
 150------------
 151#!/bin/sh
 152
 153fmt='
 154        r=%(refname)
 155        t=%(*objecttype)
 156        T=${r#refs/tags/}
 157
 158        o=%(*objectname)
 159        n=%(*authorname)
 160        e=%(*authoremail)
 161        s=%(*subject)
 162        d=%(*authordate)
 163        b=%(*body)
 164
 165        kind=Tag
 166        if test "z$t" = z
 167        then
 168                # could be a lightweight tag
 169                t=%(objecttype)
 170                kind="Lightweight tag"
 171                o=%(objectname)
 172                n=%(authorname)
 173                e=%(authoremail)
 174                s=%(subject)
 175                d=%(authordate)
 176                b=%(body)
 177        fi
 178        echo "$kind $T points at a $t object $o"
 179        if test "z$t" = zcommit
 180        then
 181                echo "The commit was authored by $n $e
 182at $d, and titled
 183
 184    $s
 185
 186Its message reads as:
 187"
 188                echo "$b" | sed -e "s/^/    /"
 189                echo
 190        fi
 191'
 192
 193eval=`git for-each-ref --shell --format="$fmt" \
 194        --sort='*objecttype' \
 195        --sort=-taggerdate \
 196        refs/tags`
 197eval "$eval"
 198------------