This was from here. Extract the patch tar -xvzf /usr/src/web100-2.5.22-200810130047.tar.gz bzip2 web100/ web100-2.6.27-2.5.22-200810130047.patch Test the patch bzip2 -dc /usr/src/linux/web100/ web100-2.6.27-2.5.22-200810130047.patch.bz2 | patch -p1 --dry-run I looked at the .patch, the diff output of many files and the file .patch.bz2 after the bzip2 command which is too also the diff output of many files, they seem to be the same. My question is why is bzip2 even needed to turn the .patch into a .patch.bz2? Is it for the redirection to std output from the -dc option for the patch command? Even if it is, why not just not just use the patch command in the form something like this:patch -p1 < patchfile? I don't see why the bzip2 is done here. Also, I think the bzip2 might have an extra space in the command after web100/, right?