I would look at AnyEvent::HTTP, which allows you to run lots (and lots) of HTTP requests in parallel. To reduce bandwidth on errors, you could first test with a HEAD request and follow up with a GET request on success. If you expect most URLs to be successfull and want the body then, I would just use a GET request.

For grouping all your requests, have a look at the ->begin method of CondVars in AnyEvent.

A rough, untested program could look something like this:

#!perl -w
use strict;
use AnyEvent;
use AnyEvent::HTTP;

my $done = AnyEvent->condvar;
while (my $url = <DATA>) {
    $url =~ s!\s+$!!;
    $done->begin( sub { $_[0]->send } );
    http_get $url, sub {
        my ($body, $headers) = @_;
        print "Retrieved $url ($headers->{Status})";
        $done->end
    };
};
print "All requests sent. Waiting for responses.\n";
$done->recv;

print "Done.\n";

__DATA__
http://localhost
http://example.com
http://google.in

[download]

Update: Remove whitespace at end of the URLs

In reply to Re: Fast fetching of HTML response code by Corion
in thread Fast fetching of HTML response code by mrguy123

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