Documentation / git-check-ref-format.txton commit Disallow '\' in ref names (a4c2e69)
   1git-check-ref-format(1)
   2=======================
   3
   4NAME
   5----
   6git-check-ref-format - Ensures that a reference name is well formed
   7
   8SYNOPSIS
   9--------
  10[verse]
  11'git check-ref-format' <refname>
  12'git check-ref-format' [--branch] <branchname-shorthand>
  13
  14DESCRIPTION
  15-----------
  16Checks if a given 'refname' is acceptable, and exits with a non-zero
  17status if it is not.
  18
  19A reference is used in git to specify branches and tags.  A
  20branch head is stored under the `$GIT_DIR/refs/heads` directory, and
  21a tag is stored under the `$GIT_DIR/refs/tags` directory.  git
  22imposes the following rules on how references are named:
  23
  24. They can include slash `/` for hierarchical (directory)
  25  grouping, but no slash-separated component can begin with a
  26  dot `.`.
  27
  28. They cannot have two consecutive dots `..` anywhere.
  29
  30. They cannot have ASCII control characters (i.e. bytes whose
  31  values are lower than \040, or \177 `DEL`), space, tilde `~`,
  32  caret `{caret}`, colon `:`, question-mark `?`, asterisk `*`,
  33  or open bracket `[` anywhere.
  34
  35. They cannot end with a slash `/` nor a dot `.`.
  36
  37. They cannot end with the sequence `.lock`.
  38
  39. They cannot contain a sequence `@{`.
  40
  41- They cannot contain a `\\`.
  42
  43These rules make it easy for shell script based tools to parse
  44reference names, pathname expansion by the shell when a reference name is used
  45unquoted (by mistake), and also avoids ambiguities in certain
  46reference name expressions (see linkgit:git-rev-parse[1]):
  47
  48. A double-dot `..` is often used as in `ref1..ref2`, and in some
  49  contexts this notation means `{caret}ref1 ref2` (i.e. not in
  50  `ref1` and in `ref2`).
  51
  52. A tilde `~` and caret `{caret}` are used to introduce the postfix
  53  'nth parent' and 'peel onion' operation.
  54
  55. A colon `:` is used as in `srcref:dstref` to mean "use srcref\'s
  56  value and store it in dstref" in fetch and push operations.
  57  It may also be used to select a specific object such as with
  58  'git-cat-file': "git cat-file blob v1.3.3:refs.c".
  59
  60. at-open-brace `@{` is used as a notation to access a reflog entry.
  61
  62With the `--branch` option, it expands a branch name shorthand and
  63prints the name of the branch the shorthand refers to.
  64
  65EXAMPLE
  66-------
  67
  68git check-ref-format --branch @{-1}::
  69
  70Print the name of the previous branch.
  71
  72
  73GIT
  74---
  75Part of the linkgit:git[1] suite