if ((fdflags = fcntl(ttyfd, F_GETFL)) == -1
|| fcntl(ttyfd, F_SETFL, fdflags & ~O_NONBLOCK) < 0)
warn("Couldn't reset non-blocking mode on device: %m");
if ((fdflags = fcntl(ttyfd, F_GETFL)) == -1
|| fcntl(ttyfd, F_SETFL, fdflags & ~O_NONBLOCK) < 0)
warn("Couldn't reset non-blocking mode on device: %m");