$GIT_DIR/info/exclude, .gitignore
A gitignore file specifies intentionally untracked files that
git should ignore. Each line in a gitignore file specifies a
pattern.
When deciding whether to ignore a path, git normally checks
gitignore patterns from multiple sources, with the following
order of precedence:
-
Patterns read from the file specified by the configuration
variable core.excludesfile.
-
Patterns read from $GIT_DIR/info/exclude.
-
Patterns read from a .gitignore file in the same directory
as the path, or in any parent directory, ordered from the
deepest such file to a file in the root of the repository.
These patterns match relative to the location of the
.gitignore file. A project normally includes such
.gitignore files in its repository, containing patterns for
files generated as part of the project build.
The underlying git plumbing tools, such as
git-ls-files(1) and git-read-tree(1), read
gitignore patterns specified by command-line options, or from
files specified by command-line options. Higher-level git
tools, such as git-status(1) and git-add(1),
use patterns from the sources specified above.
Patterns have the following format:
-
A blank line matches no files, so it can serve as a separator
for readability.
-
A line starting with # serves as a comment.
-
An optional prefix ! which negates the pattern; any
matching file excluded by a previous pattern will become
included again.
-
If the pattern does not contain a slash /, git treats it as
a shell glob pattern and checks for a match against the
pathname without leading directories.
-
Otherwise, git treats the pattern as a shell glob suitable
for consumption by fnmatch(3) with the FNM_PATHNAME flag:
wildcards in the pattern will not match a / in the pathname.
For example, "Documentation/*.html" matches
"Documentation/git.html" but not
"Documentation/ppc/ppc.html". A leading slash matches the
beginning of the pathname; for example, "/*.c" matches
"cat-file.c" but not "mozilla-sha1/sha1.c".
An example:
$ git-status
[...]
# Untracked files:
[...]
# Documentation/foo.html
# Documentation/gitignore.html
# file.o
# lib.a
# src/internal.o
[...]
$ cat .git/info/exclude
# ignore objects and archives, anywhere in the tree.
*.[oa]
$ cat Documentation/.gitignore
# ignore generated html files,
*.html
# except foo.html which is maintained by hand
!foo.html
$ git-status
[...]
# Untracked files:
[...]
# Documentation/foo.html
[...]
Another example:
$ cat .gitignore
vmlinux*
$ ls arch/foo/kernel/vm*
arch/foo/kernel/vmlinux.lds.S
$ echo '!/vmlinux*' >arch/foo/kernel/.gitignore
The second .gitignore prevents git from ignoring
arch/foo/kernel/vmlinux.lds.S.
Documentation by David Greaves, Junio C Hamano, Josh Triplett,
Frank Lichtenheld, and the git-list <git@vger.kernel.org>.