C服務器 - 響應w /他們的IP？

Question

線：

printf("Client IP : [%s]\n", inet_ntoa(cli_addr.sin_addr)); 

將打印客戶端IP在終端中。

我想把它放到「響應」，所以它也發送到客戶端。

，而不是與「測試」響應

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

char response[] = "test\r\n"; 

int main() 
{ 
    int one = 1, client_fd; 
    struct sockaddr_in svr_addr, cli_addr; 
    socklen_t sin_len = sizeof(cli_addr); 

    int sock = socket(AF_INET, SOCK_STREAM, 0); 
    if (sock < 0) 
    err(1, "can't open socket"); 

    setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(int)); 

    int port = 85; 
    svr_addr.sin_family = AF_INET; 
    svr_addr.sin_addr.s_addr = INADDR_ANY; 
    svr_addr.sin_port = htons(port); 

    if (bind(sock, (struct sockaddr *) &svr_addr, sizeof(svr_addr)) == -1) { 
    close(sock); 
    err(1, "Can't bind"); 
    } 

    listen(sock, 5); 
    while (1) { 
    client_fd = accept(sock, (struct sockaddr *) &cli_addr, &sin_len); 
    printf("Client IP : [%s]\n", inet_ntoa(cli_addr.sin_addr)); 

    if (client_fd == -1) { 
     perror("Can't accept"); 
     continue; 
    } 

    write(client_fd, response, sizeof(response) - 1); /*-1:'\0'*/ 
    close(client_fd); 
    } 
} 

Answer 1

這應該是你在尋找：

snprintf(response, sizeof response, "%s", inet_ntoa(cli_addr.sin_addr)); 

病程的

，你需要有足夠的規模來聲明響應以前存儲ip地址：

char response[16];