psame [options] file1 file2
  psame [options] file
  psame [options] -r version file
  psame [options] -r version_a -r version_b file

The first usage compares the two files. The second usage compares the latest version from Subversion, CVS or RCS against the given file. The third usage will compare the given version from Subversion, CVS or RCS against the given file. The fourth usage will compare the two versions of the given file from Subversion, CVS or RCS.

By default, blank lines, whitespace and case are ignored when comparing. The output will be a side-by-side view of matching regions with a few lines of context.