/* Connect to loopback address port 65535, unconnect, shutdown for writing, and then test sending a datagram to loopback address port 65535. */ #include "udp.h" int main(void) { signal(SIGPIPE, sigpipe); int fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP); if ( fd < 0 ) err(1, "socket"); struct sockaddr_in sin; memset(&sin, 0, sizeof(sin)); sin.sin_family = AF_INET; sin.sin_addr.s_addr = htobe32(INADDR_LOOPBACK); sin.sin_port = htobe16(65535); if ( connect(fd, (const struct sockaddr*) &sin, sizeof(sin)) < 0 ) err(1, "first connect"); struct sockaddr cos; memset(&cos, 0, sizeof(cos)); cos.sa_family = AF_UNSPEC; if ( connect(fd, (const struct sockaddr*) &cos, sizeof(cos)) < 0 ) err(1, "second connect"); if ( shutdown(fd, SHUT_WR) ) err(1, "shutdown"); char x = 'x'; if ( sendto(fd, &x, sizeof(x), 0, (const struct sockaddr*) &sin, sizeof(sin)) < 0 ) err(1, "sendto"); return 0; }