use constant SOCK_PATH => '/tmp/catsock';

socket(Server, AF_UNIX, SOCK_STREAM,0) or die "socket: $!";
setsockopt(Server, SOL_SOCKET, SO_PASSCRED, 1) or die "SO_PASSCRED: $!\n";
unlink(SOCK_PATH);
bind  (Server, sockaddr_un(SOCK_PATH)) or die "bind: $!";
listen(Server, SOMAXCONN) or die "listen: $!";

for ( $waitedpid = 0; accept(Client,Server) || $waitedpid; $waitedpid = 0, close Client) {
    next if $waitedpid;
    my $n = unpack_sockaddr_un(getsockname(Client));
    logmsg 'peer: ' . $n . "\n" . <Client>;
}