Dear Perl Monks

I want to monitor an open TCP connection on my client, as the server may have silently died or network connection is broken so I would continue to write data on my TCP socket until the send window will be 0 and eventually I may lose the data. Unfortunately the server speaks a very simple protocol without any application layer acks. It entirely relies on TCP doing the job. This I cannot change

In Linux there is a command 'ss' which gives some status information regarding socket connections. In particular it provides 'send-q' which is the count of sent TCP packets not yet acknowledged by the peer. Is there any way to get this information by a Perl function?

I would like to use it in the following way (just pseudo code) 

my $conn = IO::Socket::INET->new(PeerAddr => $host, PeerPort => $port,
+Proto => 'tcp');
die unless ($conn);
syswrite($conn, "message content");
doSomeOtherStuff();
#by now, under normal conditions, message should have reached the peer
+ and be acknowledged
my $pendingMessages = send_q($conn); #this is the function I am lookin
+g for but have not found yet
if ($pendingMessages)
{
  #perform some recovery actions here. Stop sending messages, until al
+l previous messages have been acknowledged
}

[download]

It would be so great, if someone could give me a hint how to do it. Thank you! Andreas

In reply to function to count pending packets in TCP socket by Anonymous Monk

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