Greetings Monks,
   I have a script that opens a blocking socket to a messaging server, in a while(1) loop (it is a backgrounded processs). While the script is running, I want to interrupt the socket read process, say every 1 minute, and write a status message to, say, STDERR (basically I want to monitor the process). Here is how my code looks like this: 
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);
        #.....
    }
}

[download]

Although the alarm_signal is executed (not after 60 seconds), I get the:
 Deep recursion on subroutine "Sys::AlarmCall::alarm_call" at ... error.

I feel Im not using the alarm properly here. How would you implement a way to interrupt a background process to print a debug message, periodically ?

 I forgot to mention, this elaborate alarm call, is to monitor a messaging server. The socket read, is for the advisory message from the messaging server. Basically I wanted a "watch the watcher" kind of script, hence the interrupt to write a debug message.

In reply to blocking socket and alarm by InfiniteLoop

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