command line option

software (Or "option", "flag", "switch", "option switch") An

argument to a command that modifies its function rather than

providing data. Options generally start with "-" in Unix or

"/" in MS-DOS. This is usually followed by a single letter

or occasionally a digit.

Some commands require each option to be a separate argument,

introduced by a new "-" or "/", others allow multiple option

letters to be concatenated into a single argument with a

single "-" or "/", e.g. "ls -al". A few Unix commands

(e.g. ar, tar) allow the "-" to be omitted. Some options

may or must be followed by a value, e.g. "cc prog.c -o prog",

sometimes with and sometimes without an intervening space.

getopt and getopts are commands for parsing command line

options. There is also a C library routine called getopt

for the same purpose.

(1996-12-11)