Windows Socket

The project must be setting to link wsock32.lib or ws2_32.lib. The difference between them I know is ws2_32.lib supports select function, but the other doesn't.
#include <stdio.h> #include <winsock2.h> #include <time.h> #define SENDBUF_LEN 100 #define RECVBUF_LEN 100 int main(int argc, char *argv[]) { WSADATA wsaData; int cfd; struct sockaddr_in addr; char *ip; short port; char sendbuf[SENDBUF_LEN]; char recvbuf[RECVBUF_LEN]; int recvlen=0; fd_set rfds, wfds; struct timeval timeout; int S=0; timeout.tv_sec=1; timeout.tv_usec=0; if (argc != 3) { printf("Usage:\n\t%s server_ip server_port\n" , argv[0]); return -1; } ip = argv[1]; port = (short)atoi(argv[2]); WSAStartup(0x0101, &wsaData); if ( (cfd = socket(AF_INET, SOCK_STREAM, 0) < 0){ printf("Cannot create socekt\n"); return -1; } memset(&addr, 0x00, sizeof(addr)); addr.sin_family = AF_INET; addr.sin_port = htons(port); addr.sin_addr.s_addr = inet_addr(ip); if ( connect(cfd, (struct sockaddr *)&addr, sizeof(struct sockaddr)) < 0) { printf("Cannot connect to %s\n", ip); closesocket(cfd); return -1; } FD_ZERO(&wfds); FD_SET((unsigned int)cfd, &wfds); if ( select(cfd+1, NULL, &wfds, NULL, &timeout) <=0) { printf("select fail\n"); return -1; } sprintf(sendbuf, "GET / HTTP/1.0\r\n"); if (send(cfd, sendbuf, strlen(sendbuf), 0) < 0) { printf("Cannot send\n"); closesocket(cfd); return -1; } srand(time(NULL)); while (S < 2000) { int s=0; while (s < sizeof(sendbuf)) { sendbuf[s++] = (char)rand(); } if (send(cfd, sendbuf, sizeof(sendbuf), 0) < 0) { printf("Cannot send\n"); closesocket(cfd); return -1; } S += s; } sprintf(sendbuf, "\r\n\r\n"); if (send(cfd, sendbuf, strlen(sendbuf), 0) < 0) { printf("Cannot send\n"); closesocket(cfd); return -1; } FD_ZERO(&rfds); FD_SET((unsigned int)cfd, &rfds); if ( select(cfd+1, &rfds, NULL, NULL, &timeout) <=0) { printf("select fail\n"); return -1; } if ( (recvlen=recv(cfd, recvbuf, strlen(recvbuf), 0)) < 0) { printf("Cannot recv\n"); closesocket(cfd); return -1; } recvbuf[recvlen]=0x00; printf("%s", recvbuf); return 0; }