Unified diff

File Format
Name	Unified diff
Ontology	Electronic File Formats Archiving Unified diff
Extension(s)	.patch, .diff
Released	1991
Unified diff example

Unified diff (or diff unified format, unified context diff, unidiff) is a diff format commonly used for patch files.

Identification

Unlike other diff formats, Unified diff has lines that begin with "@@".

Specifications

• Unified Diff Format - Ad-hoc specification by Guido van Rossum
• GNU Diffutilis manual: Detailed Description of Unified Format

Software

• GNU Diffutils: diff (with -u option), patch

Sample files

• Example from the GNU Diffutils manual
• http://www.apache.org/dist/httpd/patches/ ...

Links

• Wikipedia:Diff utility has a section on Unified diff