cloc counts blank lines, comment lines, and physical lines of source code in many programming languages. It is written entirely in Perl with no dependencies outside the standard distribution of Perl v5.6 and higher (code from some external modules is embedded within cloc) and so is quite portable. cloc is known to run on many flavors of Linux, Mac OS X, AIX, Solaris, IRIX, z/OS, and Windows. (To run the Perl source version of cloc on Windows one needs ActiveState Perl 5.6.1 or higher, or Cygwin installed. Alternatively one can use the Windows binary of cloc generated with perl2exe to run on Windows computers that have neither Perl nor Cygwin.)