# git-check-ref-format(1) Manual Page

## NAME

git-check-ref-format - Make sure ref name is well formed

## SYNOPSIS

git-check-ref-format <refname>

## DESCRIPTION

Checks if a given refname is acceptable, and exits non-zero if it is not.

A reference is used in git to specify branches and tags. A branch head is stored under `$GIT_DIR/refs/heads` directory, and a tag is stored under `$GIT_DIR/refs/tags` directory. git imposes the following rules on how refs are named:

1. It can include slash `/` for hierarchical (directory) grouping, but no slash-separated component can begin with a dot `.`;

2. It cannot have two consecutive dots `..` anywhere;

3. It cannot have ASCII control character (i.e. bytes whose values are lower than \040, or \177 `DEL`), space, tilde `~`, caret `^`, colon `:`, question-mark `?`, asterisk `*`, or open bracket `[` anywhere;

4. It cannot end with a slash `/`.

These rules makes it easy for shell script based tools to parse refnames, pathname expansion by the shell when a refname is used unquoted (by mistake), and also avoids ambiguities in certain refname expressions (see git-rev-parse(1)). Namely:

1. double-dot `..` are often used as in `ref1..ref2`, and in some context this notation means `^ref1 ref2` (i.e. not in ref1 and in ref2).

2. tilde `~` and caret `^` are used to introduce postfix nth parent and peel onion operation.

3. colon `:` is used as in `srcref:dstref` to mean "use srcref's value and store it in dstref" in fetch and push operations. It may also be used to select a specific object such as with git-cat-file(1) "git-cat-file blob v1.3.3:refs.c".

## GIT

Part of the git(1) suite