John the Ripper source code is distributed in the form of tarballs (tar archives) compressed with either gzip or bzip2. On a Unix-like system with GNU tar (or on Cygwin if you use Windows), please use the following command for gzip-compressed tarballs:

tar xzvf john-VERSION.tar.gz

(where VERSION is a John the Ripper version number, such as 1.7.2). For bzip2-compressed tarballs use:

tar xjvf john-VERSION.tar.bz2

On some commercial Unices, you might need to download and install gzip or bzip2 on your own (perhaps from a pre-compiled freeware archive for your flavor of Unix) and/or to use more complicated command-line syntax, such as:

gzip -dc john-VERSION.tar.gz | tar xvf -

Please refer to man (manual) pages and texinfo documentation on tar, gzip, and bzip2 for information on the command-line options.

To apply a contributed patch that was generated in accordance with our conventions and compressed with gzip, on a Unix-like system with GNU software (or on Cygwin), please use the following commands (assuming that you have just extracted the source code from a tarball as shown above):

cd john-VERSION
zcat ../john-VERSION-WHAT-REVISION.diff.gz | patch -p1 -Z

(where VERSION, WHAT, and REVISION are parts of the patch file name).

Please note that you must not enter the “src” subdirectory prior to applying patches generated in accordance with our conventions.

You may omit the -Z option to patch if you don't intend to make source code changes of your own and to regenerate the patch for others to use, as well as if you use a non-GNU patch program. Also, if the zcat shortcut is missing, replace it with gzip -dc. The resulting command might be:

gzip -dc ../john-VERSION-WHAT-REVISION.diff.gz | patch -p1

To apply an uncompressed patch, use:

patch -p1 -Z < ../john-VERSION-WHAT-REVISION.diff

or without the -Z option (that is, not setting timestamps):

patch -p1 < ../john-VERSION-WHAT-REVISION.diff