$ curl cheat.sh/

# getopt
# Parse command line arguments.
# More information: <https://www.gnu.org/software/libc/manual/html_node/Getopt.html>.

# Parse optional `verbose`/`version` flags with shorthands:
getopt --options vV --longoptions verbose,version -- --version --verbose

# Add a `--file` option with a required argument with shorthand `-f`:
getopt --options f: --longoptions file: -- --file=somefile

# Add a `--verbose` option with an optional argument with shorthand `-v`, and pass a non-option parameter `arg`:
getopt --options v:: --longoptions verbose:: -- --verbose arg

# Accept a `-r` and `--verbose` flag, a `--accept` option with an optional argument and add a `--target` with a required argument option with shorthands:
getopt --options rv::s::t: --longoptions verbose,source::,target: -- -v --target target

$

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