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GIT\-FOR\-EACH\-REF

Section: Git Manual (1)
Updated: 09/30/2007
Index Return to Main Contents
 

NAME

git-for-each-ref - Output information on each ref  

SYNOPSIS

git-for-each-ref [--count=<count>]*
                   [--shell|--perl|--python|--tcl]
                   [--sort=<key>]* [--format=<format>] [<pattern>]
 

DESCRIPTION

Iterate over all refs that match <pattern> and show them according to the given <format>, after sorting them according to the given set of <key>. If <max> is given, stop after showing that many refs. The interpolated values in <format> can optionally be quoted as string literals in the specified host language allowing their direct evaluation in that language.  

OPTIONS

<count>

By default the command shows all refs that match <pattern>. This option makes it stop after showing that many refs.

<key>

A field name to sort on. Prefix - to sort in descending order of the value. When unspecified, refname is used. More than one sort keys can be given.

<format>

A string that interpolates %(fieldname) from the object pointed at by a ref being shown. If fieldname is prefixed with an asterisk (*) and the ref points at a tag object, the value for the field in the object tag refers is used. When unspecified, defaults to %(objectname) SPC %(objecttype) TAB %(refname). It also interpolates %% to %, and %xx where xx are hex digits interpolates to character with hex code xx; for example %00 interpolates to \0 (NUL), %09 to \t (TAB) and %0a to \n (LF).

<pattern>

If given, the name of the ref is matched against this using fnmatch(3). Refs that do not match the pattern are not shown.

--shell, --perl, --python, --tcl

If given, strings that substitute %(fieldname) placeholders are quoted as string literals suitable for the specified host language. This is meant to produce a scriptlet that can directly be `eval`ed.
 

FIELD NAMES

Various values from structured fields in referenced objects can be used to interpolate into the resulting output, or as sort keys.

For all objects, the following names can be used:

refname

The name of the ref (the part after $GIT_DIR/).

objecttype

The type of the object (blob, tree, commit, tag).

objectsize

The size of the object (the same as git-cat-file -s reports).

objectname

The object name (aka SHA-1).
In addition to the above, for commit and tag objects, the header field names (tree, parent, object, type, and tag) can be used to specify the value in the header field.

Fields that have name-email-date tuple as its value (author, committer, and tagger) can be suffixed with name, email, and date to extract the named component.

The first line of the message in a commit and tag object is subject, the remaining lines are body. The whole message is contents.

For sorting purposes, fields with numeric values sort in numeric order (objectsize, authordate, committerdate, taggerdate). All other fields are used to sort in their byte-value order.

In any case, a field name that refers to a field inapplicable to the object referred by the ref does not cause an error. It returns an empty string instead.  

EXAMPLES

An example directly producing formatted text. Show the most recent 3 tagged commits::


.ft C
#!/bin/sh

git-for-each-ref --count=3 --sort='-*authordate' \
--format='From: %(*authorname) %(*authoremail)
Subject: %(*subject)
Date: %(*authordate)
Ref: %(*refname)

%(*body)
' 'refs/tags'
.ft

A simple example showing the use of shell eval on the output, demonstrating the use of --shell. List the prefixes of all heads::


.ft C
#!/bin/sh

git-for-each-ref --shell --format="ref=%(refname)" refs/heads | \
while read entry
do
        eval "$entry"
        echo `dirname $ref`
done
.ft

A bit more elaborate report on tags, demonstrating that the format may be an entire script::


.ft C
#!/bin/sh

fmt='
        r=%(refname)
        t=%(*objecttype)
        T=${r#refs/tags/}

        o=%(*objectname)
        n=%(*authorname)
        e=%(*authoremail)
        s=%(*subject)
        d=%(*authordate)
        b=%(*body)

        kind=Tag
        if test "z$t" = z
        then
                # could be a lightweight tag
                t=%(objecttype)
                kind="Lightweight tag"
                o=%(objectname)
                n=%(authorname)
                e=%(authoremail)
                s=%(subject)
                d=%(authordate)
                b=%(body)
        fi
        echo "$kind $T points at a $t object $o"
        if test "z$t" = zcommit
        then
                echo "The commit was authored by $n $e
at $d, and titled

    $s

Its message reads as:
"
                echo "$b" | sed -e "s/^/    /"
                echo
        fi
'

eval=`git-for-each-ref --shell --format="$fmt" \
        --sort='*objecttype' \
        --sort=-taggerdate \
        refs/tags`
eval "$eval"
.ft


 

Index

NAME
SYNOPSIS
DESCRIPTION
OPTIONS
FIELD NAMES
EXAMPLES