lua_altgetopt is a module for Lua programming language for processing application's arguments the same way BSD/GNU getopt_long(3) functions do. Main features and goals: 1) compatibility to SUS "Utility Syntax Guidelines" http://www.opengroup.org/onlinepubs/009695399/basedefs/xbd_chap12.html#tag_12_02 guidelines 3-13. 2) This module is for plain Lua 2) No extra dependencies 3) No hooks, no functional tricks ;-) 4) Support for long options, e.g. compatibility with getopt_long(3) C function present in *BSD and GNU libc. 5) Long options may optionally have one-char synonym or other long synonym 6) Strict error checking (checks for an incorrect use of options) 7) alt_getopt.lua is a Lua module.