Count, or compute differences of, physical lines of source code in the given files (may be archives such as compressed tarballs or zip files) and/or recursively below the given directories. It is written entirely in Perl, using only modules the standard distribution. -Count, or compute differences of, physical lines of source code in the given files (may be archives such as compressed tarballs or zip files) and/or recursively below the given directories. It is written entirely in Perl, using only modules　the standard distribution.