I would like to run script as a cronjob and only get the image if it has been updated.

Honing in on this, I'd say a better bet is to use LWP::Simple's mirror method:

use LWP::Simple qw(mirror);
my $result = mirror("http://host.example.com/url/foo.jpg", "localfile.
+jpg");
if ($result == 304) {
  print "no update needed\n":
} elsif ($result = 200) {
  print "New image has arrived!\n";
} else {
  die "Bad mirror status: $result\n";
}
[download]

This is presuming that the image is either a static file, updated from time to time, or that the image is dynamically generated but with a proper handling of "if-modified-since".

Using mirror with a proper webserver guarantees minimal web traffic. I use it to mirror web pages and images a lot. I've even written a few columns using it. {grin}

-- Randal L. Schwartz, Perl hacker
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