View source for Perl Notes/IO::Socket::INET client server

'''Client'''

<pre>
#!/usr/bin/perl -w                    
                                      
use strict;                           
use IO::Socket;                       
                                      
# initialize host and port            
my $port = 7890;                      
my $server = "1.2.3.3";
my $verbose = 1;                      

my $sock = new IO::Socket::INET (
    PeerAddr => $server,
    PeerPort => $port,
    Proto => 'tcp');

die "Could not create socket: $!\n" unless $sock;

$now = time;
$verbose && print "$now Socket created\n";

my $Now = 0;
my $Tower = 56;
my $ServerNum = 3;
my $Range = 0;

my $line;

eval { $line = <$sock>; };
if ( $@) { die "$now Failed to read first line\n"; }

$now = time;
if ( ! $line =~ /HELO/ ) {
    die "$now Server not ready\n";
}  else {
    $now = time;
    print "$now got HELO\n"
}

print $sock "ShowGraph $Now:$Tower:$ServerNum:$Range:ScanQueue:Scan Queue Length:average\n";

$now = time;
$verbose && print "$now Sent Show graph\n";

eval { $line = <$sock>; };
if ( $@) { die "$now Failed to get response to Showgreaph\n" }

$now = time;
if ( $line =~ /OK/ ) {
    print "$now Got OK: " .$line;
} else {
    print "$now Error: $line \n";
}
$now = time;
print "$now Sending quit\n";
print $sock "QUIT\n";

close($sock) or die "close: $!";
</pre>

'''Server'''
<pre>
#!/usr/bin/perl -w

use strict;
use IO::Socket;

my $port = 7890;
my $proto = getprotobyname('tcp');
my $now ;
my $verbose =1;
$|++;

my $server = new IO::Socket::INET (
        LocalHost => '1.2.3.4',
        LocalPort => $port,
        Proto => $proto,
        Listen => 10,
        Reuse => 1,
    );
die "Could not create server socket: $!\n" unless $server;

sub myexit {
    my $sig  = shift;
    print STDOUT time . " $$ Caught $sig on server side\n" ;
    # close($server);
};

sub Wait {
    print STDOUT time . " Wait called (SIG CHLD signal)\n";
    wait; #wait needed to keep <defunct> pids from building up
}

$SIG{CHLD} = \&Wait;
$SIG{QUIT} = \&myexit;
$SIG{INT}  = \&myexit;

$verbose && print time . " Server Socket created\n";

my $client;

while ( $client = $server->accept()) {

    $verbose && print time ." Accepted socket\n";

    next if my $pid = fork;
    die "fork  - $!\n" unless defined $pid;
    $verbose && print time . " Forked!\n";
    $verbose && print STDOUT time . " Child Closing Server\n";
    # close ( $server );

    select $client;

    $now = time;
    $verbose && print "$now child selected\n";


    while(my $line = <$client>) {
        chomp $line;

        if ( $line =~ /QUIT/ ) {
            $now = time;
            $verbose && print STDOUT "$now RECV QUIT command, QUITING\n";
            next;
        } elsif ( $line =~ /SpecialCommand\s{1}?(.*)/ ) {
            $now = time;
            $verbose && print STDOUT "$now RECV command Special Command arg: $1\n";
            $verbose && print STDOUT "$now SEND OK: Special Command Result\n";
            $verbose && print $client "OK: Showgraph\n";
        } else {
            $verbose && print STDOUT "$now RECV Unrecognized command: $line\n";
            $verbose && print $client "ERROR: Unrecognized command\n";
        }
    }
    $verbose && print STDOUT time . " child closing client\n";
    close ($client);
    exit(0);
} continue {
    $verbose && print STDOUT time . " Parent Continue, closing client\n";
    close($client);
    $verbose && print STDOUT time . " Parent client closed, sending CHLD to children\n";
    kill CHLD => -$$;
}