builtin-reflog.c: don't install new reflog on write failure
[git/git.git] / Documentation / git-reflog.txt
1 git-reflog(1)
2 =============
3
4 NAME
5 ----
6 git-reflog - Manage reflog information
7
8
9 SYNOPSIS
10 --------
11 'git reflog' <subcommand> <options>
12
13 DESCRIPTION
14 -----------
15 The command takes various subcommands, and different options
16 depending on the subcommand:
17
18 [verse]
19 git reflog expire [--dry-run] [--stale-fix] [--verbose]
20 [--expire=<time>] [--expire-unreachable=<time>] [--all] <refs>...
21
22 git reflog [show] [log-options] [<ref>]
23
24 Reflog is a mechanism to record when the tip of branches are
25 updated. This command is to manage the information recorded in it.
26
27 The subcommand "expire" is used to prune older reflog entries.
28 Entries older than `expire` time, or entries older than
29 `expire-unreachable` time and are not reachable from the current
30 tip, are removed from the reflog. This is typically not used
31 directly by the end users -- instead, see linkgit:git-gc[1].
32
33 The subcommand "show" (which is also the default, in the absence of any
34 subcommands) will take all the normal log options, and show the log of
35 the reference provided in the command-line (or `HEAD`, by default).
36 The reflog will cover all recent actions (HEAD reflog records branch switching
37 as well). It is an alias for 'git log -g --abbrev-commit --pretty=oneline';
38 see linkgit:git-log[1].
39
40 The reflog is useful in various git commands, to specify the old value
41 of a reference. For example, `HEAD@\{2\}` means "where HEAD used to be
42 two moves ago", `master@\{one.week.ago\}` means "where master used to
43 point to one week ago", and so on. See linkgit:git-rev-parse[1] for
44 more details.
45
46
47 OPTIONS
48 -------
49
50 --stale-fix::
51 This revamps the logic -- the definition of "broken commit"
52 becomes: a commit that is not reachable from any of the refs and
53 there is a missing object among the commit, tree, or blob
54 objects reachable from it that is not reachable from any of the
55 refs.
56 +
57 This computation involves traversing all the reachable objects, i.e. it
58 has the same cost as 'git prune'. Fortunately, once this is run, we
59 should not have to ever worry about missing objects, because the current
60 prune and pack-objects know about reflogs and protect objects referred by
61 them.
62
63 --expire=<time>::
64 Entries older than this time are pruned. Without the
65 option it is taken from configuration `gc.reflogExpire`,
66 which in turn defaults to 90 days.
67
68 --expire-unreachable=<time>::
69 Entries older than this time and are not reachable from
70 the current tip of the branch are pruned. Without the
71 option it is taken from configuration
72 `gc.reflogExpireUnreachable`, which in turn defaults to
73 30 days.
74
75 --all::
76 Instead of listing <refs> explicitly, prune all refs.
77
78 --verbose::
79 Print extra information on screen.
80
81 Author
82 ------
83 Written by Junio C Hamano <junkio@cox.net>
84
85 Documentation
86 --------------
87 Documentation by Junio C Hamano and the git-list <git@vger.kernel.org>.
88
89 GIT
90 ---
91 Part of the linkgit:git[7] suite