Question regarding patches

[devendra.aaru]

On Wed, Dec 19, 2012 at 5:13 AM, Shraddha Kamat <sh2008ka at gmail.com> wrote:
> On Wed, 2012-12-19 at 13:58 +0400, Lijo Antony wrote:
>> On 12/19/2012 12:47 PM, Shraddha Kamat wrote:
>> > Sorry if this is not relevant to kernel. But since I am
>> > patching the kernel - Please consider this as a uber beginner
>> > question to ask on this mailing list - forgive me for that.
>> >
>> > Now my question is -
>> >
>> > What "@@ -321,7 +321,8 @@" mean in this snippet from the patch -
>> >
>> > diff --git a/exec.h b/exec.h
>> > index 722c620..6abb687 100644
>> > --- a/exec.h
>> > +++ b/exec.h
>> > @@ -321,7 +321,8 @@ static void acct_arg_size(struct linux_binprm *bprm,
>> > unsigned long pages);
>> >
>>
>> http://www.gnu.org/software/diffutils/manual/html_node/Detailed-Unified.html
>> http://www.artima.com/weblogs/viewpost.jsp?thread=164293
>>
>> -lijo
>>
> But I don't see any mention of the "index" field here //
> see line "index 722c620..6abb687 100644". What does this mean ?
>
the index 7222...6bbb are may be the git ids or some git's references...

100644 is the file mode.