There is a difference between the getopt() method and the getopts() method which is the boolean one you want. Read the docs for details. With getopt() if you supply the command line argument -p12 then $opt_p = '12'. If you go -p then you just get an undefined value. With getopts() if you go -p you get then $opt_p = '1' which is what I imagine you want. If you don't supply the -p command line arg then you get an undefined value. This is presumably fixed version. 1 lousy 's' is all that was missing!

use strict;
use warnings;
use Getopt::Std;
use LWP::UserAgent;

our($opt_p);
getopts('p'); # getopts() not getopt()

print "\nThe value in \$opt_p is ";
print defined($opt_p) ? "'$opt_p'" : "undefined";

my $agent = LWP::UserAgent->new();
($opt_p == 1 ? $agent->env_proxy() : $agent->proxy(http => $opt_p)) if
+ (defined($opt_p));
[download]

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print

Here is the difference between the getopt() method and the getopts() method.

getopt()

C:\>type getopt.pl

use Getopt::Std;
our($opt_p);
getopt('p');
print "Using the getopt() method \$opt_p is ";
print defined $opt_p ? "'$opt_p'" : "undefined";

C:\>perl getopt.pl
Using the getopt() method $opt_p is undefined

C:\>perl getopt.pl -p
Using the getopt() method $opt_p is undefined

C:\>perl getopt.pl -p123
Using the getopt() method $opt_p is '123'
[download]

getopts() with an s!

C:\>type getopts.pl

use Getopt::Std;
our($opt_p);
getopts('p');
print "Using the getopts() method \$opt_p is ";
print defined $opt_p ? "'$opt_p'" : "undefined";

C:\>perl getopts.pl
Using the getopts() method $opt_p is undefined

C:\>perl getopts.pl -p
Using the getopts() method $opt_p is '1'

C:\>perl getopts.pl -p123
Unknown option: 1
Unknown option: 2
Unknown option: 3
Using the getopts() method $opt_p is '1'
C:\>
[download]

cheers

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print

Okay, thanks for all the help. I'm halfway there now, I think. So if I wanted to get $switch to equal 1 if the switch was on its own and $arg to equal the argument, I should be able to this...

use Getopt::Std;
our($opt_p);
getopt('p');
my $arg = $opt_p;
getopts('p');
my $switch = $opt_p;

print "Switch is $switch and arg is $arg\n";
[download]

Sadly, when run:

>perl stuff.pl
Switch is  and arg is  # Okay so far...

>perl stuff.pl -p
Switch is  and arg is  # No, switch should equal 1...

>perl stuff.pl -p http://www.proxy.com
Switch is http://www.proxy.com and arg is http://www.proxy.com  # Shou
+ldn't switch equal 1 here too?
[download]

So, any input on how to get the desired behaviour, or maybe I shouldn't be going about it like this anyway?

I don't generaly use the Getopt module. I parse stuff myself to get the behaviour I want. You get the command line args in @ARGV. Here is an example with minimal flexibility and error checking. It takes a -p flag and and optional proxy arg.

C:\>type test.pl

my ($switch, $proxy) = @ARGV;
$switch = ($switch eq '-p') ? 1 : 0;
$proxy = defined $proxy ? $proxy : 'undef';
print "Switch is '$switch', and proxy is '$proxy'\n";

C:\>perl test.pl

Switch is '0', and proxy is 'undef'

C:\>perl test.pl -p

Switch is '1', and proxy is 'undef'

C:\>perl test.pl -p http://proxy.foo.com/proxy.pac

Switch is '1', and proxy is 'http://proxy.foo.com/proxy.pac'

C:\>perl test.pl http://proxy.foo.com/proxy.pac

Switch is '0', and proxy is 'undef'

C:\>
[download]

cheers

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print

There is an excellent tutorial on this stuff by grinder here on PM. You will find it at Parsing your script's command line

cheers

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print