SunOS 5.6 Perl 5.6.1

I have the following:

$SIG{'CHLD'} = 'IGNORE';

open(STDOUT, ">>my.log");
STDOUT->autoflush(1);
open(STDERR, ">>my.log");
STDERR->autoflush(1);

my $sock = new IO::Socket::INET (LocalHost => 'foo.com',
                                 LocalPort => 1234,
                                 Proto     => 'tcp',
                                 Listen    => 5,
                                 ReuseAddr => 1
                                );

$sock or die("Failed to create sock: $!.");
ONE: while ( 1 ) {
    my $new_sock = $sock->accept;
    if (!defined($new_sock)) {
      print(STDERR "Warning: Bad connect.\n");
          next ONE;
    }

    if ( ! defined($child = fork) ) {
      print("Could not fork: $!.\n");
      exit(1);
    }

    $child && next;
    <do something as the child>
    shutdown($new_sock,2);
    close($new_sock);
    exit(0);
} # End ONE
close($sock);

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My questions are:

1. For the close($new_sock);, should I be checking the return value for this. I wasn't sure why a close on a socket connection would fail.

2. For the close($sock);, is this necessary/useful and can/should I check for a failure? Also, would shutdown($sock,2); do anything useful? I didn't think so, but I saw it while googling for example code.

3. If the child process is executing a command like system("echo Hello");, I need to reap child processes before closing the forked child process so as not to leave "zombies" right? Or is my handling that via capturing the CHLD signal ($SIG{'CHLD'} = 'IGNORE';) before I even start up the socket sufficient? I wasn't sure I needed to do one of these:

while ( my $child_process = waitpid(-1,WNOHANG) > 0 ) {
}

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before I close the child each time.

4. In Perl 5.6.1, after each accepted connection do I need to reset STDERR and STDOUT that I set prior creating the socket? Previously in Perl 5.005_02 I was having to reset these with each new connection. If that's the same, can someone tell me why?

I think that's it. I thank you for any help you can offer.

Regards,

NOTE: Updated to remove filehandle comment so we can better focus on the questions. Thanks -sk

Shannon Kerr

2005-10-21 Retitled by planetscape, as per Monastery guidelines
Original title: 'Socket'

In reply to Handling sockets in a server by skerr1

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