how to debug xinit?

[Carlos Eduardo Rodrigues Diógenes]

Hi,

I'm trying to debug xinit to see how it's avaliate the ViewPort in the 
xorg.conf. But when I'm using GDB, it's never get in this point, it's 
output an message "Server error." and exits the program. This occur in 
these lines:

    if (startServer(server) > 0
     && startClient(client) > 0) {
        pid = -1;
        while (pid != clientpid && pid != serverpid
#ifndef X_NOT_POSIX
               && gotSignal == 0
#endif
            )
            pid = wait(NULL);
    }
    signal(SIGQUIT, SIG_IGN);
    signal(SIGINT, SIG_IGN);
    signal(SIGHUP, SIG_IGN);
    signal(SIGPIPE, SIG_IGN);

    shutdown();

the first line is 451 in xc/programs/xinit/xinit.c and when I use 'step' 
in gdb to verify whats ocurr in 'startServer' I get the error. If I use 
'next' it pass, but the validation of the xorg.conf pass through and I 
can't see how it's done.

Thanks,

Carlos.