Introduction

A patch is exactly what the word says: a small piece of code used to repair a breach. It is normally a plain text file containing only the differences between the current version of the code and the fixed version.

Often patches are also used to submit enhancements.

Generating a Patch

The preferred way of creating a patch is to create it against latest CVS. This ensures that the patch works with the latest version of the source code and makes it easier to apply the patch.

To generate the patch you need to check out a copy of the source code from CVS. Look a the CVS Howto for the details.

After you have made the changes to the source code and made sure it compiles and works as expected, you can create the patch file using the command cvs diff -u > /path/to/patchfile.patch.

It is recommended to include the diff -u line in ~/.cvsrc.

If you do not have access to CVS you can generate the patch against the latest release.

To generate the patch you will need two copies of the source code: one that is unmodified and one containing your changes to the source. Start by downloading the source code of the latest release, extract it and make a copy of the entire source directory. After you have made your changes to one of the source directories and made sure it compiles and works as expected, you can create the patch file using the command diff -ru /path/to/unmodified/source /path/to/modified/source > /path/to/patchfile.patch.

Sending a Patch

The preferred way to submit a patch is via the Bug Tracker. The patch can be reviewed there in public and other suggestions can be discussed.