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Assig 4 - accept(2) interrupted by SIGCHLD

On Wed, 9 Apr 1997, Rob Flores wrote:

> Writing signal handlers for both is an exercise in portability.
> My problem occurs when I try to run a signal handler in SunOS signal mode:
>  When my childs exit, the signal handler interrupts my accept system call
> to the socket, and the server can no longer accept connections on the
> socket. (this info courtesy of perror and erno).

Yes, this is an old problem. The portable solution is to check if
accept(2) returns with -1 and errno==EINTR, and in this case
loop back to accept again.

Something like the following should do.

        while (! end_of_the_show) {
                sock=accept(blah, growl, grumble);
                if (-1==sock) {
                        if (EINTR==errno) {
                                continue; /* Restart accept */
                        }
                        else {
                                perror("Ouch ouch accept");
                                end_of_the_show=TRUE;
                        }
                }
                else {
                        process_connection(sock);
                }
        }

Ciao
Franco