For installation instructions see the Section called Installing Patch-2.5.4 in Chapter 6.
Patch (2.5.4):
ftp://ftp.gnu.org/gnu/patch/
The patch program modifies a file according to a patch file. A patch file usually is a list, created by the diff program, that contains instructions on how an original file needs to be modified.
Installed program: patch
patch modifies files according to a patch file. A patch file normally is a difference listing created with the diff program. By applying these differences to the original files, patch creates the patched versions. Using patches instead a entire new tarballs to keep your sources up-to-date can save you a lot of download time.
Patch depends on: Bash, Binutils, Coreutils, Diffutils, GCC, Glibc, Grep, Make, Sed.