use Sys::AlarmCall;

#open socket 
#....
&socket_read();

sub alarm_signal {
    print STDERR "Received alarm\n";
    &socket_read();
};

sub socket_read {

    while(1){
        alarm_call(60, 'alarm_signal');
        my $len = $socket->sysread($line,1024);
        #.....
    }
}