/* Shut down for writing and then test sending a datagram. */ #include "udp.h" int main(void) { signal(SIGPIPE, sigpipe); int fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP); if ( fd < 0 ) err(1, "socket"); if ( shutdown(fd, SHUT_WR) ) err(1, "shutdown"); struct sockaddr_in sin; memset(&sin, 0, sizeof(sin)); sin.sin_family = AF_INET; sin.sin_addr.s_addr = htobe32(BLACKHOLE_HOST); sin.sin_port = htobe16(BLACKHOLE_PORT); char x = 'x'; if ( sendto(fd, &x, sizeof(x), 0, (const struct sockaddr*) &sin, sizeof(sin)) < 0 ) err(1, "sendto"); return 0; }