Here's my web crawler: 
#!/usr/bin/perl -w

use LWP::Simple;
use HTML::SimpleLinkExtor;
use Data::Dumper;
use LWP::RobotUA;
use HTTP::Response;

open(LINKS,">>/home/baelnorn/urls.txt");

while(<LINKS>) {
chomp $_;
my $ua = LWP::RobotUA->new("theusefulbot", "akurtis3 at yahoo.com");
$ua->delay(.10/60);
my $content= $ua->get("$_");
my $extor = HTML::SimpleLinkExtor->new();
$extor->parse($content);

my @links=$extor->a;

foreach $links (@links) {
if($links=~m/^\// and $_=~m/\/$/) {
substr($links, 0, 1);
my $address="$_ $links";
print LINKS "$address\n";
} else  {
    if($links=~m/^http:\/\/|^www./) {
    print LINKS "$links\n";
}

if($links != ~m/^\// and $_=~m/\/$/) {
    my $address="$_ $links";
    print LINKS  "$address\n";
}

if($links != ~m/^\// and $_ != ~m/\/$/) {
    my $address="$_ \ $links";
    print LINKS  "$address\n";
}

}
}
print $content;
}

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When I run it it says: Useless use of substr in void context at newcrawler.pl line 23. I think that it is getting trapped in my if statements, which are meant to deal with links like /foo/foo.htm and foo.htm Any ideas, Thanks,

20040220 Edit by BazB: Changed title from 'Web Crawler'

In reply to Useless use of substr in void context by mkurtis

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