unix环境IPC编程之套接字（二），UDP编程实例

/******************************************************************************

*  *

*         udp_server.c  *

*  *

******************************************************************************/

#include <stdio.h>

#include <sys/types.h>

#include <sys/socket.h>

#include <string.h>

#include <netinet/in.h>

#define PORT 8888

#define MSG_SIZE 128

int main()

{

    int sockfd;

    struct sockaddr_in server_addr;

    struct sockaddr_in client_addr;

    char buffer[MSG_SIZE];

    int addrlen;

    int n;

    /* 1.创建套接字 */

    sockfd = socket(AF_INET, SOCK_DGRAM, 0);

    /* 2.1设置地址 */

    bzero(&server_addr,sizeof(struct sockaddr_in));

    server_addr.sin_family = AF_INET;

    server_addr.sin_port = htons(PORT);

    server_addr.sin_addr.s_addr = htonl(INADDR_ANY);

    /* 2.2绑定地址 */

    bind(sockfd,(struct sockaddr *)&server_addr,

                    sizeof(struct sockaddr));

    /* 3.接收数据 */

    while(1)

    {

        addrlen = sizeof(struct sockaddr);

        bzero(buffer, sizeof(buffer));

        n = recvfrom(sockfd, buffer, MSG_SIZE, 0, (struct sockaddr *)&client_addr,&addrlen);

        buffer[n] = 0;

        printf("Server received: %s\n", buffer);

    }

    /* 4.关闭套接字 */

    close(sockfd);

    return 0;

}

/******************************************************************************

*  *

*         udp_client.c  *

*  *

******************************************************************************/

#include <stdio.h>

#include <sys/types.h>

#include <sys/socket.h>

#include <netinet/in.h>

#define BUF_SIZE 128

#define PORT 8888

int main(int argc, char *argv[])

{

    int sockfd;

    char buffer[128];

    struct sockaddr_in server_addr;

    if(argc != 2)

    {

        printf("Usage: %s server_ip\n",argv[0]);

        exit(1);

    }

    /* 1.创建套接字 */

    sockfd = socket(AF_INET, SOCK_DGRAM, 0);

    /* 初始化服务器的地址 */

    bzero(&server_addr,sizeof(struct sockaddr_in));

    server_addr.sin_family = AF_INET;

    server_addr.sin_port = htons(PORT);

    inet_aton(argv[1],&server_addr.sin_addr);

    while(1)

    {

        printf("Please input char: \n");

        fgets(buffer, BUF_SIZE, stdin);

        /* 2.发送数据 */

        sendto(sockfd, buffer, strlen(buffer), 0,(struct sockaddr *)&server_addr, sizeof(struct sockaddr));

        bzero(buffer, BUF_SIZE);

    }

    /* 3.关闭套接字 */

    close(sockfd);

    return 0;

}