Update Nice (more excellent) link indeed merlyn (thanks!), but just how is a newbie to think of abigail? ;-)

--
I'd like to be able to assign to an luser

Not quite. Add "abigail" into the mix, and you end up with this most excellent link.

-- Randal L. Schwartz, Perl hacker

I don't think anyone mentioned the Find::URI module. I've never used it but I would hope it would either do a good job of this or you'd submit a patch for it based on other information in this thread. (:

I like the one Albannach mentions above except that I'd be sure to add "," to the list of punctuation marks! My limited experience with URL-matching regexen shows that the trailing comma is the number one problem for them.

I looked over the link merlyn gave and didn't see any regular expressions and was forced to actually start reading. (: The first line has a link to the regex that the discussed program generates. Somehow I cannot recommend the use of such a huge beast for the original requested purpose. Based on a very casual reading, I think that monster would actually match trailing punctation such as the period at the end of this sentence that also ends in a URL, http://www.perl.org/index.html.

        - tye (but my friends call me "Tye")

#!/usr/local/bin/perl -w

use strict;

my $file = "/export/home/ssesar/example";
my $line;
open (FILE, $file) || die "\n$!";

while ($line = <FILE>) {
    chomp $line;
    if ($line  =~ m/^http\:\/\//) {
        print "line = $line\n";
    }
    else {
        print "Sorry, dude\n";
  }
}
[download]

As long as that's your only line. You could have just said:

@ARGV = qw(/export/home/ssesar/example);
print "line = $_" for <>;
[download]

for the accuracy you give. See the other answers in this thread for things which actually detect valid URLs, and reject bad ones.

-- Randal L. Schwartz, Perl hacker

Thanks! Much easier!