A small example of Linux socket

Server:

#include <stdlib.h>#include <sys/types.h>#include <stdio.h>#include <sys/socket.h>#include <netinet/in.h>#include <string.h>int main(int argc, char** argv){    int serv_sock, cli_sock;    char buf[1024];    struct sockaddr_in seraddr, cliaddr;    if((serv_sock=socket(AF_INET, SOCK_STREAM, 0)) == -1){    printf("create socket fail\n");exit(1);    }     printf("create socket ok\n");        bzero(&seraddr, sizeof(struct sockaddr_in));    seraddr.sin_family = AF_INET;    seraddr.sin_addr.s_addr = htonl(INADDR_ANY);    seraddr.sin_port = htons(6666);    printf("s_addr = %#x ,port : %#x\r\n", seraddr.sin_addr.s_addr, seraddr.sin_port);    if(bind(serv_sock, (struct sockaddr*)(&seraddr), sizeof(struct sockaddr)) == -1){printf("bind socket fail\n");    exit(1);    }    printf("bind ok\n");    if(listen(serv_sock, 5) == -1){printf("listen socket fail\n");    }    printf("listen ok\n");    while(1){int len = sizeof(struct sockaddr);if((cli_sock = accept(serv_sock, (struct sockaddr*)(&cliaddr), &len)) == -1){printf("accept fail\n");exit(1);}    printf("accept ok!\r\nServer start get connect from %#x : %#x\r\n",ntohl(cliaddr.sin_addr.s_addr),ntohs(cliaddr.sin_port));   int ret = read(cli_sock, buf, sizeof(buf));printf("read from client %s\n", buf);    close(cli_sock);     }     close(serv_sock);     exit(0);}

Client:

#include <stdlib.h>#include <sys/types.h>#include <stdio.h>#include <sys/socket.h>#include <netinet/in.h>#include <string.h>int main(){int sock;struct sockaddr_in ser_addr;char buff[1024];if((sock=socket(AF_INET, SOCK_STREAM, 0)) == -1){printf("client create socket fail\n");exit(1);}printf("create socket ok\n");bzero(&ser_addr, sizeof(struct sockaddr_in));ser_addr.sin_family = AF_INET;ser_addr.sin_port = htons(6666);;ser_addr.sin_addr.s_addr = inet_addr("192.168.1.104");if(connect(sock, (struct sockaddr *)(&ser_addr), sizeof(struct sockaddr)) == -1){printf("connect fail\n");exit(1);}printf("connect ok\n");//buff = {'a', 'b'};buff[0] = 'a';buff[1] = 'b';buff[2] = 'f';if(write(sock, buff, strlen(buff)) == -1){printf("write fail\n");exit(1);}printf("write ok\n");close(sock);return 0;}