PERL 옵션 설정

HELP 옵션과 VERBOSE 설정을 예로

my $options = {}; # `my' defines a local variable.

getopts("hv", $options);

$debug_mode = $options->{v};

sub print_usage_and_exit {

my $fh = shift || *STDOUT;

my $message = shift;

print $fh $message, "\n" if defined $message;

print $fh <<END;

Usage: $0 [-h] [-v] [-v] <keywords_file> [<output_file>]

keywords_file             - input filename which lists keywords

output_file               - output filename to write

Options -

-h          shows this help message

-v          enables verbose mode

END

exit;

}

print_usage_and_exit if $options->{h};