原理大家都懂
环境- ubuntu14.04 直接上代码
#include#include #include #include #include #include #include #include #include #include int main(int argc, char *argv[]){ int sockfd; char recvbuffer[1024*4]; // char buffer[1024]; struct sockaddr_in server_addr; struct hostent *host; int portnumber, nbytes; int i = 0; char *t; char send_buffer[] = "GET / HTTP/1.1\r\nUser-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/79.0.3945.117 Safari/537.36\r\n\r\n"; if (argc != 3) { fprintf(stderr, "Usage :%s hostname portnumber\a\n", argv[0]); exit(1); } if ((host = gethostbyname(argv[1])) == NULL) { herror("Get host name error\n"); exit(1); } printf("h_name: %s\n", host->h_name); //IP地址 for (; host->h_addr_list[i]; i++) { printf("IP addr %d: %s\n", i + 1, inet_ntoa(*(struct in_addr *)host->h_addr_list[i])); } if ((portnumber = atoi(argv[2])) < 0) { fprintf(stderr, "Usage:%s hostname portnumber\a\n", argv[0]); exit(1); } if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) { fprintf(stderr, "Socket Error:%s\a\n", strerror(errno)); exit(1); } bzero(&server_addr, sizeof(server_addr)); server_addr.sin_family = AF_INET; server_addr.sin_port = htons(portnumber); server_addr.sin_addr = *((struct in_addr *)host->h_addr_list[0]); if (connect(sockfd, (struct sockaddr *)(&server_addr), sizeof(struct sockaddr)) == -1) { fprintf(stderr, "Connect error:%s\n", strerror(errno)); exit(1); } printf("Request:\n%s",send_buffer); send(sockfd, send_buffer, strlen(send_buffer), 0); recv(sockfd, recvbuffer, sizeof(recvbuffer), 0); t = strstr(recvbuffer,"\r\n\r\n"); *t = (char)0; printf("\nResponse:\n%s\n", recvbuffer); close(sockfd); exit(0);}
编译
gcc -o tcp_client tcp_client.c
运行
./tcp_client www.baidu.com 80
输入了http请求头部和响应头
运行结果