1The GetoptLong class allows you to parse command line options similarly to the 2GNU getopt_long() C library call. Note, however, that GetoptLong is a pure Ruby 3implementation. 4 5GetoptLong allows for POSIX-style options like --file as well as single letter 6options like -f 7 8The empty option -- (two minus symbols) is used to end option processing. This 9can be particularly important if options have optional arguments. 10