This manual describes how to compare and merge files using GNU diff and patch. Comparing and merging files is a common activity for software developers. These programs make it easy to find and apply changes. GNU diff is part of the GNU diffutils package, a complete set of programs for handling differences between groups of files. GNU patch allows these differences to be distributed in an efficient format. This is a printed copy of the offical GNU diffutils manual. It documents all the diffutils programs (diff, cmp, sdiff, diff3), plus GNU patch. GNU diff and patch are free software. For each copy of this manual sold, $1 will be donated to the Free Software Foundation.
The authors of this manual are the original developers of the GNU diffutils programs:
David MacKenzie wrote many of the GNU utilities and their documentation. He was the principal designer and author of Autoconf, and prototyped Automake. He has worked for the FSF and Cygnus (now Redhat).
Paul Eggert is a faculty member in the Computer Science Department at UCLA. He has contributed to many important GNU projects, including Autoconf, Bison, Diffutils, GNU Emacs, GCC, the GNU C Library, the GNU core utilities, and GNU tar. He is currently a member of the GNU C Library Steering Committee and is a maintainer or developer for far too many GNU projects.
Richard Stallman founded the GNU Project in 1984. He is the principal or initial author of GNU Emacs, the GNU C Compiler, the GNU Debugger GDB and parts of other packages. He is the President of the Free Software Foundation (FSF).