spw=p[1];
spr=p[0];
if (fcntl(spw, F_SETFL, fcntl(spw, F_GETFL)|O_NONBLOCK)==-1) {
fatal_perror("start_signal_handling: fcntl(O_NONBLOCK)");
}
spw=p[1];
spr=p[0];
if (fcntl(spw, F_SETFL, fcntl(spw, F_GETFL)|O_NONBLOCK)==-1) {
fatal_perror("start_signal_handling: fcntl(O_NONBLOCK)");
}