Allows you to combine getopt with getopts and also get rid of the need for --longopt=x

OPTOUT=1 - Only display all received arguments, do not parse

SHORTDASH=1 - Print one dash before short parsed arguments

PARSER=1 - Separate the key and its value from each other with a straight line (|)

./sortopts "a:b:c:d:-" "one:,two,three::" \
           -a1 -b 2 -c3 -d 4 \
	   --one --two --three 3

bash
getopt (from util-linux)

Use legacyopts. There, for parsing short arguments, getopts is used - a utility built into the bash.

Keep in mind that handling x:: and x:- arguments will NOT work in this version of the script.