hmmm...bad news for me then. The perl client is simple. It doesn't use IO::Socket. 
#!/usr/bin/perl -w
use strict;

# simple client

use Socket;
use IO::Handle;

socket(TSOCK, PF_UNIX, SOCK_STREAM,0);
connect(TSOCK, sockaddr_un("/tmp/testsock")) or print "ERROR!";

while (defined(my $messg = <TSOCK>)) {
    print $messg;
    print TSOCK "Hello server!\n";
    TSOCK->flush;
}

[download]
Both servers work fine with their counter-part (but I wrote them to do that). I haven't tried to change anything to debug the "c<->perl" problem, because I have a hard time understanding what could be wrong (they are just exchanging strings) and thought I would ask here to find out if there is something I'm unaware of.

If I connect the above perl client to the c server, it accepts a new connection, but it does not recieve the "Hello", and the client does not recieve messages from the server.

What could go wrong, considering the c server works fine with connections to other c programs?

In reply to Re^2: Local socket model by Anonymous Monk
in thread Local socket model by Anonymous Monk

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