I'm trying to catch UDP broadcasts (this means the receiver address is set to 255.255.255.255), on a specific port. I've the following program: 
#!/usr/bin/perl

use strict;
use warnings;

use IO::Socket::INET;

my $port   = getservbyname 'bootps', 'udp'; 
my $socket = IO::Socket::INET -> new (LocalPort  => $port, 
                                      Broadcast  =>  1,
                                      Proto      => 'udp')
             or die "Failed to bind to socket: $@";

my $mess;     
while ($socket -> recv ($mess, 1024)) {  
    print "Saw a bootp request.\n";
}

__END__

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If I run this program, it creates the socket (the output of netstat -a inet confirms that: 
udp        0      0 *:bootps                *:*

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), but it gets blocked in the recv call - the while body never gets executed. tcpdump however shows that many requests come by.

I've looked in the documentation and on the web, and while I've found examples of UDP servers in Perl, I haven't found an example of a server that listens to broadcasts.

What am I doing wrong here?

Abigail

In reply to Intercepting UDP broadcasts by Abigail-II

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