Patch (Unix) - Usage Examples

Usage Examples

To create a patch, one could run the following command in a shell:

$ diff -u oldFile newFile > mods.diff # -u tells diff to output unified diff format

To apply a patch, one could run the following command in a shell:

$ patch < mods.diff

This tells patch to apply the changes to the specified files described in mods.diff. Patches to files in subdirectories require the additional -pnumber option, where number is 1 if the base directory of the source tree is included in the diff, and 0 otherwise.

Patches can be undone, or reversed, with the '-R' option:

$ patch -R < mods.diff

If the file is not identical to the version the diff was generated against, the patch will not be able to be applied cleanly. For example, if lines of text are inserted at the beginning, the line numbers referred to in the patch will be incorrect. patch is able to recover from this, by looking at nearby lines to relocate the text to be patched. It will also recover when lines of context (for context and unified diffs) are altered; this is described as fuzz.

Read more about this topic:  Patch (Unix)

Famous quotes containing the words usage and/or examples:

    ...Often the accurate answer to a usage question begins, “It depends.” And what it depends on most often is where you are, who you are, who your listeners or readers are, and what your purpose in speaking or writing is.
    Kenneth G. Wilson (b. 1923)

    There are many examples of women that have excelled in learning, and even in war, but this is no reason we should bring ‘em all up to Latin and Greek or else military discipline, instead of needle-work and housewifry.
    Bernard Mandeville (1670–1733)