getops

getopts optionstring variable [argumentlist]

• It will use the positional parameters unless the optional argumentlist is supplied.

• getopts puts the matching option character into your variable and puts the number of the next char into OPTIND.

• If the option is not matched, variable is set to "?" and an error message is written to stderr (unless ":" is the first character of optionstring to suppress that behaviour).

• Dash arguments that have arguments themselves (like cut -f 5) can be followed by a colon in optionlist, and the next item in the parameter list will be assigned to OPTARG for use in the script.

• Processing stops when the first non-dash argument is found.