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.\" Title: git-patch-id
.\" Author: [FIXME: author] [see http://docbook.sf.net/el/author]
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.\" Date: 04/08/2014
.\" Manual: Git Manual
.\" Source: Git 1.9.1
.\" Language: English
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.TH "GIT\-PATCH\-ID" "1" "04/08/2014" "Git 1\&.9\&.1" "Git Manual"
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.SH "NAME"
git-patch-id \- Compute unique ID for a patch
.SH "SYNOPSIS"
.sp
.nf
\fIgit patch\-id\fR <
.fi
.sp
.SH "DESCRIPTION"
.sp
A "patch ID" is nothing but a SHA\-1 of the diff associated with a patch, with whitespace and line numbers ignored\&. As such, it\(cqs "reasonably stable", but at the same time also reasonably unique, i\&.e\&., two patches that have the same "patch ID" are almost guaranteed to be the same thing\&.
.sp
IOW, you can use this thing to look for likely duplicate commits\&.
.sp
When dealing with \fIgit diff\-tree\fR output, it takes advantage of the fact that the patch is prefixed with the object name of the commit, and outputs two 40\-byte hexadecimal strings\&. The first string is the patch ID, and the second string is the commit ID\&. This can be used to make a mapping from patch ID to commit ID\&.
.SH "OPTIONS"
.PP
.RS 4
The diff to create the ID of\&.
.RE
.SH "GIT"
.sp
Part of the \fBgit\fR(1) suite