Linux C网络编程中最简单的例子(源码)

/* A simple server in the internet domain using TCP The port number is passed as an argument */ #include <stdio.h> /*标准的输入输出流*/ #include <sys/types.h> /*定义系统的数据类型*/ #include <sys/socket.h>/**/ #include <netinet/in.h> void error(char *msg) { perror(msg); exit(1); } int main(int argc, char *argv[]) { int sockfd, newsockfd, portno, clilen; char buffer[256]; struct sockaddr_in serv_addr, cli_addr; int n; if (argc < 2) { fprintf(stderr,"ERROR, no port provided\n"); exit(1); } sockfd = socket(AF_INET, SOCK_STREAM, 0); if (sockfd < 0) error("ERROR opening socket"); bzero((char *) &serv_addr, sizeof(serv_addr)); portno = atoi(argv[1]); serv_addr.sin_family = AF_INET; serv_addr.sin_addr.s_addr = INADDR_ANY; serv_addr.sin_port = htons(portno); if (bind(sockfd, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0) error("ERROR on binding"); listen(sockfd,5); clilen = sizeof(cli_addr); newsockfd = accept(sockfd, (struct sockaddr *) &cli_addr, &clilen); if (newsockfd < 0) error("ERROR on accept"); bzero(buffer,256); n = read(newsockfd,buffer,255); if (n < 0) error("ERROR reading from socket"); printf("Here is the message: %s\n",buffer); n = write(newsockfd,"I got your message",18); if (n < 0) error("ERROR writing to socket"); return 0; }