1.一段简单的客户服务器程序

[root@liumengli net]# cat client1.c
#include "/programe/net/head.h"
#include "stdio.h"
#include "stdlib.h"

int main(int argc, char ** argv) {
        int sockfd, n;
        int my;
        char buf[100];
        struct sockaddr_in servaddr;

        if((sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
                printf("create socket error\n");
                exit(1);
        }

        bzero(&servaddr, sizeof(servaddr));
        servaddr.sin_family = AF_INET;
        servaddr.sin_port = htons(atoi(argv[2]));

        if(inet_pton(AF_INET, argv[1], &servaddr.sin_addr) < 0) {
                printf("inet_pton error\n");
                exit(1);
        }

        if((my = connect(sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr))) < 0) {
                printf("connect error\n");
                exit(1);
        }

        n = read(sockfd, buf, 100);
        buf[n] = '\0';

        printf("%s\n", buf);
        printf("%d\n", my);
        getchar();
        exit(0);
}
[root@liumengli net]# cat head.h
#include "sys/types.h"
#include "sys/socket.h"
#include "netinet/in.h"
#include "arpa/inet.h"
#include "netdb.h"
[root@liumengli net]# cat server1.c
#include "/programe/net/head.h"
#include "stdio.h"
#include "stdlib.h"

int main(int argc, char ** argu) {
        int listenfd, connfd;
        struct sockaddr_in servaddr;
        char buf[] = "hello world";
        int n;

        listenfd = socket(AF_INET, SOCK_STREAM, 0);
        bzero(&servaddr, sizeof(servaddr));
        servaddr.sin_family = AF_INET;
        servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
        servaddr.sin_port = htons(atoi(argu[1]));
        bind(listenfd, (struct socket_addr *)&servaddr, sizeof(servaddr));
        listen(listenfd, n);
        for(;;) {
                connfd = accept(listenfd, (struct socket_addr *)NULL, NULL);
                write(connfd, buf, strlen(buf));
        }
}

 

unix网络编程最简单的例子，这里不做注释了，后面几篇将围绕这个做详细介绍。