Selecting the patch Input Format

patch normally determines which diff format the patch file uses by examining its contents. For patch files that contain particularly confusing leading text, you might need to use one of the following options to force patch to interpret the patch file as a certain format of diff. The output formats listed here are the only ones that patch can understand.

-c

--context

context diff.

-e

--ed

ed script.

-n

--normal

normal diff.

-u

--unified

unified diff.