#! perl -slw
use strict;
use threads;
use IO::Socket;

my $pause :shared = 0;
async{
   while( <STDIN> ) {
       chomp;
       if( /^suspend/i ) {
           $pause = 1;
       }
       elsif( /^resume/i ) {
           $pause = 0;
       }
   }
}->detach;

my $lsn = IO::Socket::INET->new( Listen => 1, LocalPort => 12345 );

while( my $fname = <*.png> ) {
    my $client = $lst->accept;
    print $client $fname;
}

##</code><code>##

#! perl -slw
use strict;
use IO::Socket;

my $server = shift;

while( 1 ) {
    my $svr = IO::Socket->new( $server );
    my $fname = <$svr>;
    close $svr;
    ## Process $fname.
}