NAME
----
-git-diff-index - Compares content and mode of blobs between the index and repository
+git-diff-index - Compare a tree to the working tree or index
SYNOPSIS
--------
+[verse]
'git diff-index' [-m] [--cached] [<common diff options>] <tree-ish> [<path>...]
DESCRIPTION
-----------
-Compares the content and mode of the blobs found via a tree
-object with the content of the current index and, optionally
-ignoring the stat state of the file on disk. When paths are
-specified, compares only those named paths. Otherwise all
-entries in the index are compared.
+Compares the content and mode of the blobs found in a tree object
+with the corresponding tracked files in the working tree, or with the
+corresponding paths in the index. When <path> arguments are present,
+compares only paths matching those patterns. Otherwise all tracked
+files are compared.
OPTIONS
-------
-m::
By default, files recorded in the index but not checked
out are reported as deleted. This flag makes
- 'git-diff-index' say that all non-checked-out files are up
+ 'git diff-index' say that all non-checked-out files are up
to date.
-Output format
--------------
include::diff-format.txt[]
Operating Modes
---------------
You can choose whether you want to trust the index file entirely
-(using the '--cached' flag) or ask the diff logic to show any files
+(using the `--cached` flag) or ask the diff logic to show any files
that don't match the stat state as being "tentatively changed". Both
of these operations are very useful indeed.
Cached Mode
-----------
-If '--cached' is specified, it allows you to ask:
+If `--cached` is specified, it allows you to ask:
show me the differences between HEAD and the current index
- contents (the ones I'd write using 'git-write-tree')
+ contents (the ones I'd write using 'git write-tree')
For example, let's say that you have worked on your working directory, updated
some files in the index and are ready to commit. You want to see exactly
Example: let's say I had renamed `commit.c` to `git-commit.c`, and I had
done an `update-index` to make that effective in the index file.
`git diff-files` wouldn't show anything at all, since the index file
-matches my working directory. But doing a 'git-diff-index' does:
+matches my working directory. But doing a 'git diff-index' does:
torvalds@ppc970:~/git> git diff-index --cached HEAD
-100644 blob 4161aecc6700a2eb579e842af0b7f22b98443f74 commit.c
You can see easily that the above is a rename.
In fact, `git diff-index --cached` *should* always be entirely equivalent to
-actually doing a 'git-write-tree' and comparing that. Except this one is much
+actually doing a 'git write-tree' and comparing that. Except this one is much
nicer for the case where you just want to check where you are.
-So doing a 'git-diff-index --cached' is basically very useful when you are
+So doing a `git diff-index --cached` is basically very useful when you are
asking yourself "what have I already marked for being committed, and
what's the difference to a previous tree".
---------------
The "non-cached" mode takes a different approach, and is potentially
the more useful of the two in that what it does can't be emulated with
-a 'git-write-tree' + 'git-diff-tree'. Thus that's the default mode.
+a 'git write-tree' + 'git diff-tree'. Thus that's the default mode.
The non-cached version asks the question:
show me the differences between HEAD and the currently checked out
tree - index contents _and_ files that aren't up-to-date
which is obviously a very useful question too, since that tells you what
-you *could* commit. Again, the output matches the 'git-diff-tree -r'
+you *could* commit. Again, the output matches the 'git diff-tree -r'
output to a tee, but with a twist.
The twist is that if some file doesn't match the index, we don't have
a backing store thing for it, and we use the magic "all-zero" sha1 to
show that. So let's say that you have edited `kernel/sched.c`, but
-have not actually done a 'git-update-index' on it yet - there is no
+have not actually done a 'git update-index' on it yet - there is no
"object" associated with the new state, and you get:
- torvalds@ppc970:~/v2.6/linux> git diff-index HEAD
- *100644->100664 blob 7476bb......->000000...... kernel/sched.c
+ torvalds@ppc970:~/v2.6/linux> git diff-index --abbrev HEAD
+ :100644 100664 7476bb... 000000... kernel/sched.c
i.e., it shows that the tree has changed, and that `kernel/sched.c` has is
not up-to-date and may contain new stuff. The all-zero sha1 means that to
get the real diff, you need to look at the object in the working directory
directly rather than do an object-to-object diff.
-NOTE: As with other commands of this type, 'git-diff-index' does not
+NOTE: As with other commands of this type, 'git diff-index' does not
actually look at the contents of the file at all. So maybe
`kernel/sched.c` hasn't actually changed, and it's just that you
touched it. In either case, it's a note that you need to
-'git-update-index' it to make the index be in sync.
+'git update-index' it to make the index be in sync.
NOTE: You can have a mixture of files show up as "has been updated"
and "is still dirty in the working directory" together. You can always
show a valid sha1, and the "not in sync with the index" ones will
always have the special all-zero sha1.
-
-Author
-------
-Written by Linus Torvalds <torvalds@osdl.org>
-
-Documentation
---------------
-Documentation by David Greaves, Junio C Hamano and the git-list <git@vger.kernel.org>.
-
GIT
---
Part of the linkgit:git[1] suite