in reply to Getopts and required args

Use Getopt::Long.

Breifly, here's an example of what your code may end up looking like:
use strict;
use warnings;
use Getopt::Long;
use vars qw($opt_u $opt_h $opt_a $opt_l);

&GetOptions('l=s','u','h','a') || exit 1;

print "Option found: u\n" if ($opt_u);
print "Option found: h\n" if ($opt_h);
print "Option found: a\n" if ($opt_a);
if ($opt_l) {
    print "Option found: l\n";
    print "  with value: $opt_l\n";
} else {
    print "You must specify -l\n";
    exit 1;
}

[download]
Note that 'l=s' means that l must be specified with a value, otherwise, GetOptions() fails.

Hope that helps,
Shendal

Replies are listed 'Best First'.
RE: Re: Getopts and required args
by husker (Chaplain) on Jun 22, 2000 at 20:34 UTC
    In this example, it appears that -l is a required switch, which it isn't. Or am I reading this wrong? 
    if ($opt_l) {
    print "Option found: l\n";
    print "  with value: $opt_l\n";
} else {
    print "You must specify -l\n";
    exit 1;
}

    [download]
    In other words, not having $opt_l should NOT be an error... only a NULL $opt_l. And in perl, is there a difference?
[reply]
[d/l]
      Well, in my example it is required. I must have misunderstood your question. If you want to require -l to be paired with a value, but not specifying -l is okay, too, try this:

      use strict;
use warnings;
use Getopt::Long;
use vars qw($opt_u $opt_h $opt_a $opt_l);

#Note that l=s says that l requires an option
#   l:s means that it is optional
#   I have chosen the option method here so that
#   I can handle it how I want programatically
&GetOptions('l:s','u','h','a') || exit 1;

print "Option found: u\n" if ($opt_u);
print "Option found: h\n" if ($opt_h);
print "Option found: a\n" if ($opt_a);
if (defined $opt_l) {
    print "Option found: l\n";
    if ($opt_l) {
    print "  with value: $opt_l\n";
    } else {
    print "  No value specified.\n";
    }
}

      [download]
[reply]
[d/l]

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