7 getopt, getopts - Process single-character switches with switch clustering
13 getopt('oDI'); # -o, -D & -I take arg. Sets $opt_* as a side effect.
14 getopt('oDI', \%opts); # -o, -D & -I take arg. Values in %opts
15 getopts('oif:'); # -o & -i are boolean flags, -f takes an argument
16 # Sets $opt_* as a side effect.
17 getopts('oif:', \%opts); # options as above. Values in %opts
21 The getopt() function processes single-character switches with switch
22 clustering. Pass one argument which is a string containing all switches
23 that take an argument. For each switch found, sets $opt_x (where x is the
24 switch name) to the value of the argument if an argument is expected,
25 or 1 otherwise. Switches which take an argument don't care whether
26 there is a space between the switch and the argument.
28 The getopts() function is similar, but you should pass to it the list of all
29 switches to be recognized. If unspecified switches are found on the
30 command-line, the user will be warned that an unknown option was given.
31 The getopts() function returns true unless an invalid option was found.
33 Note that, if your code is running under the recommended C<use strict
34 'vars'> pragma, you will need to declare these package variables
39 For those of you who don't like additional global variables being created, getopt()
40 and getopts() will also accept a hash reference as an optional second argument.
41 Hash keys will be x (where x is the switch name) with key values the value of
42 the argument or 1 if no argument is specified.
44 To allow programs to process arguments that look like switches, but aren't,
45 both functions will stop processing switches when they see the argument
46 C<-->. The C<--> will be removed from @ARGV.
48 =head1 C<--help> and C<--version>
50 If C<-> is not a recognized switch letter, getopts() supports arguments
51 C<--help> and C<--version>. If C<main::HELP_MESSAGE()> and/or
52 C<main::VERSION_MESSAGE()> are defined, they are called; the arguments are
53 the output file handle, the name of option-processing package, its version,
54 and the switches string. If the subroutines are not defined, an attempt is
55 made to generate intelligent messages; for best results, define $main::VERSION.
57 If embedded documentation (in pod format, see L<perlpod>) is detected
58 in the script, C<--help> will also show how to access the documentation.
60 Note that due to excessive paranoia, if $Getopt::Std::STANDARD_HELP_VERSION
61 isn't true (the default is false), then the messages are printed on STDERR,
62 and the processing continues after the messages are printed. This being
63 the opposite of the standard-conforming behaviour, it is strongly recommended
64 to set $Getopt::Std::STANDARD_HELP_VERSION to true.
66 One can change the output file handle of the messages by setting
67 $Getopt::Std::OUTPUT_HELP_VERSION. One can print the messages of C<--help>
68 (without the C<Usage:> line) and C<--version> by calling functions help_mess()
69 and version_mess() with the switches string as an argument.
74 @EXPORT = qw(getopt getopts);
76 # uncomment the next line to disable 1.03-backward compatibility paranoia
77 # $STANDARD_HELP_VERSION = 1;
79 # Process single-character switches with switch clustering. Pass one argument
80 # which is a string containing all switches that take an argument. For each
81 # switch found, sets $opt_x (where x is the switch name) to the value of the
82 # argument, or 1 if no argument. Switches which take an argument don't care
83 # whether there is a space between the switch and the argument.
86 # getopt('oDI'); # -o, -D & -I take arg. Sets opt_* as a side effect.
89 my ($argumentative, $hash) = @_;
90 $argumentative = '' if !defined $argumentative;
95 while (@ARGV && ($_ = $ARGV[0]) =~ /^-(.)(.*)/) {
96 ($first,$rest) = ($1,$2);
97 if (/^--$/) { # early exit if --
101 if (index($argumentative,$first) >= 0) {
107 $rest = shift(@ARGV);
110 $$hash{$first} = $rest;
113 ${"opt_$first"} = $rest;
114 push( @EXPORT, "\$opt_$first" );
123 push( @EXPORT, "\$opt_$first" );
134 local $Exporter::ExportLevel = 1;
140 return $OUTPUT_HELP_VERSION if defined $OUTPUT_HELP_VERSION;
141 return \*STDOUT if $STANDARD_HELP_VERSION;
146 exit 0 if $STANDARD_HELP_VERSION;
148 print {output_h()} <<EOM;
149 [Now continuing due to backward compatibility and excessive paranoia.
150 See ``perldoc $p'' about \$$p\::STANDARD_HELP_VERSION.]
154 sub version_mess ($;$) {
157 if (@_ and defined &main::VERSION_MESSAGE) {
158 main::VERSION_MESSAGE($h, __PACKAGE__, $VERSION, $args);
160 my $v = $main::VERSION;
161 $v = '[unknown]' unless defined $v;
163 $myv .= ' [paranoid]' unless $STANDARD_HELP_VERSION;
165 $perlv = sprintf "%vd", $^V if $] >= 5.006;
167 $0 version $v calling Getopt::Std::getopts (version $myv),
168 running under Perl version $perlv.
173 sub help_mess ($;$) {
176 if (@_ and defined &main::HELP_MESSAGE) {
177 main::HELP_MESSAGE($h, __PACKAGE__, $VERSION, $args);
179 my (@witharg) = ($args =~ /(\S)\s*:/g);
180 my (@rest) = ($args =~ /([^\s:])(?!\s*:)/g);
181 my ($help, $arg) = ('', '');
183 $help .= "\n\tWith arguments: -" . join " -", @witharg;
184 $arg = "\nSpace is not required between options and their arguments.";
187 $help .= "\n\tBoolean (without arguments): -" . join " -", @rest;
189 my ($scr) = ($0 =~ m,([^/\\]+)$,);
190 print $h <<EOH if @_; # Let the script override this
192 Usage: $scr [-OPTIONS [-MORE_OPTIONS]] [--] [PROGRAM_ARG1 ...]
196 The following single-character options are accepted:$help
198 Options may be merged together. -- stops processing of options.$arg
201 if ( defined $0 and $0 ne '-e' and -f $0 and -r $0
202 and open my $script, '<', $0 ) {
204 $has_pod = 1, last if /^=(pod|head1)/;
207 print $h <<EOH if $has_pod;
216 # getopts('a:bc'); # -a takes arg. -b & -c not. Sets opt_* as a
220 my ($argumentative, $hash) = @_;
221 my (@args,$first,$rest,$exit);
226 @args = split( / */, $argumentative );
227 while(@ARGV && ($_ = $ARGV[0]) =~ /^-(.)(.*)/s) {
228 ($first,$rest) = ($1,$2);
229 if (/^--$/) { # early exit if --
233 my $pos = index($argumentative,$first);
235 if (defined($args[$pos+1]) and ($args[$pos+1] eq ':')) {
238 ++$errs unless @ARGV;
239 $rest = shift(@ARGV);
242 $$hash{$first} = $rest;
245 ${"opt_$first"} = $rest;
246 push( @EXPORT, "\$opt_$first" );
255 push( @EXPORT, "\$opt_$first" );
266 if ($first eq '-' and $rest eq 'help') {
267 version_mess($argumentative, 'main');
268 help_mess($argumentative, 'main');
272 } elsif ($first eq '-' and $rest eq 'version') {
273 version_mess($argumentative, 'main');
278 warn "Unknown option: $first\n";
289 local $Exporter::ExportLevel = 1;