using getopts::long and testing for command line options

[c]

I'd like to be able to test and see if a user has entered any command line flags for a script. If they do not, I'd like to echo an error, however, if they do, I'd like the script to continue forward. I have:

#!/usr/bin/perl -w

use strict;
use Getopt::Long;

my $in;

GetOptions (    'in=s' => \$in );

if ($#ARGV < 0) {
  print "you need to put in some command line options!\n";
  exit(1);
}

however, even when i run ./script --in something the warning is still echoed to the screen. Am i misinterpretting $#ARGV or does getopts::long decrease the value of $#ARGV as it reads in options?

humbly -c

[ozone]

according to the GetOpt cpan page:
"The command line options are taken from array @ARGV. Upon completion of GetOptions, @ARGV will contain the rest (i.e. the non-options) of the command line."

So your @ARGV should be empty

[idnopheq]

Move the GetOptions line after the @ARGV test. The Getopt modules clear their elements from @ARGV when they process.

HTH
--
idnopheq
Apply yourself to new problems without preparation, develop confidence in your ability to to meet situations as they arrise.

~ Shunryu Suzuki

[MZSanford]

If you want to check for any incorrect options, look at the return code from GetOptions(), and it will be 0 if there were any unknown options (or incorrect ones) provided.

---

_{can't sleep clowns will eat me}
-- MZSanford