edit: I am completely rephrasing the question, with new code.

I am having problems with IO::Socket pretending it has a connection when it does not. I wrote the following proof-of-concept code because the production code had too much extraneous information. A (a.pl) connects to B (b.pl) and sends data. C (c.pl) then *also* connects to B, and thinks it is sending data to B, but B never gets anything from C.

What I want here is not to have A and C both talk successfully to B. What I want is for C to recognize B is busy with A, and perform the appropriate task.

#!/usr/bin/perl
# a.pl
use strict;
use warnings;
use IO::Socket;
use less 'java';        #;-)
my $b_address = '127.0.0.1';    #IP of box A
my $b_port = '8888';        #Port number guipartner set to on A
my $eol = "\015\012";   #sets end of line chracters for socket transmi
+ssions
my $skipA = 0;
my $socketA = new IO::Socket::INET (
                PeerAddr => $b_address,
                PeerPort => $b_port,
                Proto => 'tcp',
                ) or $skipA = 1;
local $/=$eol;          #set default EOL to $eol so chomp works
while (!$skipA) {
    print $socketA "a.pl sends \$skipA=$skipA", $eol;
    print "message sent\n";
    sleep 2;
}
print "socket not available\n";
close $socketA;

#!/usr/bin/perl
# b.pl
use strict;
use warnings;
use IO::Socket;
use less 'java';    #;-)
my $eol = "\015\012";    #sets end of line chracters for socket transm
+issions
while (1){        #continuous loop: wait for socket connections until 
+end of time
    my $sock = new IO::Socket::INET (
        LocalPort => '8888',
        Proto => 'tcp',
        Listen => 1,
        ) or die "Could not create socket: $!\n";
    my $newsock = $sock->accept();        #waiting for incoming socket
+ connection
    while (my $incoming = <$newsock>){
        local $/=$eol;            #set default EOL to $eol so chomp wo
+rks
        chomp($incoming);
        print "received: $incoming\n";
    }
    close $newsock;
    close $sock;
}

#!/usr/bin/perl
# c.pl
use strict;
use warnings;
use IO::Socket;
use less 'java';        #;-)
my $b_address = '127.0.0.1';    #IP of box A
my $b_port = '8888';        #Port number guipartner set to on A
my $eol = "\015\012";   #sets end of line chracters for socket transmi
+ssions
my $skipC = 0;
my $socketC = new IO::Socket::INET (
                PeerAddr => $b_address,
                PeerPort => $b_port,
                Proto => 'tcp',
                ) or $skipC = 1;
local $/=$eol;          #set default EOL to $eol so chomp works
while (!$skipC) {
    print $socketC "c.pl sends \$skipC=$skipC", $eol;
    print "message sent\n";
    sleep 2;
}
print "socket not available\n";
close $socketC;

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In reply to IO::Socket *always* making connection? by wolfger

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