projects / thirdparty / git.git / blame
| Commit | Line | Data |
|---|---|---|
| 12905637 JH |
1 | git-symbolic-ref(1) |
| 2 | =================== | |
| 3 | ||
| 4 | NAME | |
| 5 | ---- | |
| 6 | git-symbolic-ref - read and modify symbolic refs | |
| 7 | ||
| 8 | SYNOPSIS | |
| 9 | -------- | |
| 10 | 'git-symbolic-ref' <name> [<ref>] | |
| 11 | ||
| 12 | DESCRIPTION | |
| 13 | ----------- | |
| 14 | Given one argument, reads which branch head the given symbolic | |
| 15 | ref refers to and outputs its path, relative to the `.git/` | |
| 16 | directory. Typically you would give `HEAD` as the <name> | |
| 17 | argument to see on which branch your working tree is on. | |
| 18 | ||
| 19 | Give two arguments, create or update a symbolic ref <name> to | |
| 20 | point at the given branch <ref>. | |
| 21 | ||
| 22 | Traditionally, `.git/HEAD` is a symlink pointing at | |
| 23 | `refs/heads/master`. When we want to switch to another branch, | |
| 24 | we did `ln -sf refs/heads/newbranch .git/HEAD`, and when we want | |
| 25 | to find out which branch we are on, we did `readlink .git/HEAD`. | |
| 26 | This was fine, and internally that is what still happens by | |
| 27dedf0c JH |
27 | default, but on platforms that do not have working symlinks, |
| 28 | or that do not have the `readlink(1)` command, this was a bit | |
| 12905637 JH |
29 | cumbersome. On some platforms, `ln -sf` does not even work as |
| 30 | advertised (horrors). | |
| 31 | ||
| 32 | A symbolic ref can be a regular file that stores a string that | |
| 33 | begins with `ref: refs/`. For example, your `.git/HEAD` *can* | |
| 34 | be a regular file whose contents is `ref: refs/heads/master`. | |
| 35 | This can be used on a filesystem that does not support symbolic | |
| 36 | links. Instead of doing `readlink .git/HEAD`, `git-symbolic-ref | |
| 37 | HEAD` can be used to find out which branch we are on. To point | |
| 38 | the HEAD to `newbranch`, instead of `ln -sf refs/heads/newbranch | |
| 39 | .git/HEAD`, `git-symbolic-ref HEAD refs/heads/newbranch` can be | |
| 40 | used. | |
| 41 | ||
| 42 | Currently, .git/HEAD uses a regular file symbolic ref on Cygwin, | |
| 43 | and everywhere else it is implemented as a symlink. This can be | |
| 44 | changed at compilation time. | |
| 45 | ||
| 46 | Author | |
| 47 | ------ | |
| 48 | Written by Junio C Hamano <junkio@cox.net> | |
| 49 | ||
| 50 | GIT | |
| 51 | --- | |
| 52 | Part of the gitlink:git[7] suite |