[C/C++] Socket 範例

說明:
Socket Server/Client範例

Code:

Server=>

#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <time.h> 

int socket_server(int port)
{
    int listenfd = 0, connfd = 0;
    struct sockaddr_in serv_addr; 
    char buffer[1024];

    listenfd = socket(AF_INET, SOCK_STREAM, 0);
    memset(&serv_addr, '0', sizeof(serv_addr));   

    serv_addr.sin_family = AF_INET;
    serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    serv_addr.sin_port = htons(port); 

    bind(listenfd, (struct sockaddr*)&serv_addr, sizeof(serv_addr)); 
    listen(listenfd, 10); 
    connfd = accept(listenfd, (struct sockaddr*)NULL, NULL); 
    
    memset(buffer, '0', sizeof(buffer)); 
    strcpy(buffer, "I get server message!");
    
    if (write(connfd, buffer, strlen(buffer)) < 0)
    {
        printf("\n Error : Write Failed \n");
        return 1;
    } 
    
    memset(buffer, '\0', sizeof(buffer)); 
    
    if (read(connfd, buffer, sizeof(buffer)) < 0)
    {
        printf("\n Error : Read Failed \n");
        return 1;
    } 
    
    printf("buffer : [%s]\n\n", buffer);
    close(connfd);
    return 0;
}

int main(int argc, char *argv[])
{
    socket_server(5000);
    return 0;
}

Client=>

#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <netdb.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <arpa/inet.h> 

int socket_client(char *ip, int port)
{
    int sockfd = 0;
    char buffer[1024];
    struct sockaddr_in serv_addr; 

    memset(buffer, '\0',sizeof(buffer));
    
    if((sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
    {
        printf("\n Error : Could not create socket \n");
        return 1;
    } 

    memset(&serv_addr, '0', sizeof(serv_addr)); 

    serv_addr.sin_family = AF_INET;
    serv_addr.sin_port = htons(port); 

    if(inet_pton(AF_INET, ip, &serv_addr.sin_addr)<=0)
    {
        printf("\n inet_pton error occured\n");
        return 1;
    } 

    if(connect(sockfd, (struct sockaddr *)&serv_addr, sizeof(serv_addr)) < 0)
    {
       printf("\n Error : Connect Failed \n");
       return 1;
    } 

    if (read(sockfd, buffer, sizeof(buffer)) < 0)
    {
        printf("\n Error : Read Failed \n");
        return 1;
    } 
    
    printf("buffer : [%s]\n\n", buffer);

    sleep(1);
    
    memset(buffer, '\0', sizeof(buffer));
    strcpy(buffer, "I get client message!");
    
    if (write(sockfd, buffer, strlen(buffer)) < 0) 
    {
        printf("\n Error : Write Failed \n");
        return 1;
    } 
    
    close(sockfd);
    
    return 0;
}

int main(int argc, char *argv[])
{
    socket_client("127.0.0.1", 5000);
    
    return 0;
}

Result:

buffer : [I get server message!]

buffer : [I get client message!]