/* Connect to the loopback address port 65535 and then test receiving a datagram. */ #include "udp.h" int main(void) { 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, "connect"); char x; ssize_t amount = recv(fd, &x, sizeof(x), MSG_DONTWAIT); if ( amount < 0 ) err(1, "recv"); if ( amount == 0 ) puts("EOF"); return 0; }