丙 |套接字不接受通过 telnet 的连接

Question

首先，这是我的代码：

#include "database.h"
#include "pop3.h"
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/stat.h>
#include <fcntl.h>

#define PORT 1234

DBRecord fbPopHost = { "host", "pop3", "localhost" };
DBRecord fbPopPort = { "port", "pop3", "8110" };


int main(void) {
    int pop3socket;
    int clientSocket;
    int len;
    int binden;
    int zuhoeren;

    struct sockaddr_in mailserver;

    /* Socket erstellen */
    pop3socket = socket(AF_INET, SOCK_STREAM, 0);
    if(pop3socket < 0) {
        perror("Fehler beim Erstellen des Sockets!");
    }

    /* IP und Port festlegen mithilfe von Bind */
    memset(&mailserver, 0, sizeof(mailserver)); 
    mailserver.sin_family = AF_INET;
    mailserver.sin_addr.s_addr = htonl(INADDR_ANY);
    mailserver.sin_port = htons(1234);
    binden = (pop3socket, (struct sockaddr*)&mailserver, sizeof(mailserver));
    if(binden < 0) {
        perror("Fehler beim Binden des Sockets");
    }

    /* Warteschlange einrichten */
    zuhoeren = listen(pop3socket, 5);
    if(zuhoeren == -1) {
        perror("Fehler beim Listen");
    }

    /* Verbindung(en) akzeptieren */
    struct sockaddr_in pop3client; /* Client Infos */

    for(;;) {
        len = sizeof(struct sockaddr);
        clientSocket = accept(pop3socket, (struct sockaddr*)&pop3client, &len);
        if(clientSocket < 0) {
            perror("Fehler beim Accepten der Verbindung");
        }
        process_pop3(clientSocket);
    }


}

当我尝试通过 telnet 打开连接时：

telnet localhost 1234

它悲伤地说：

Trying 127.0.0.1... telnet: Unable to connect to remote host: Connection refused

当我启动程序时，它会监听连接，所以我不知道出了什么问题。有人可以帮助我吗，它越来越令人沮丧？

感谢您的帮助！

Answer 1

您实际上应该在这一行中调用 bind()：

binden = (pop3socket, (struct sockaddr*)&mailserver, sizeof(mailserver));

:-)

丙 |套接字不接受通过 telnet 的连接

C | socket not accepting connection via telnet

c

sockets

telnet