无法连接到本地主机

Question

我正在运行 linux mint 并在命令终端中输入了一些命令来连接到我的本地主机，但它一直说连接失败。

这是我输入的内容：

echo "echo test" | ./<my executable> localhost <port #>

这是我的连接代码：

  int r = connect(sock, addrList->ai_addr, addrList->ai_addrlen);
  if (r < 0) {
    printf("Connection failed\n");
    exit(1);
  }

这里是完整的代码：

int main(int argc, char *argv[]) {
  if (argc != 3) {
    printf("Invalid arguments\n");
    exit(1);
  }

  char *serverIP = argv[1]; /*Server hostname*/
  char *portNumber = argv[2]; /*Port Number*/
  void *numericAddress;
  char addrBuffer[INET6_ADDRSTRLEN];
  in_port_t port;
  char buffer_stdin[65535];
  char buffer_stdout[65535];
  int bytes_read = 0;
  int bytes_written = 0;

  /*getting integral number of string representation of port number*/
  in_port_t servPort = atoi(argv[2]);

  /*------------------get binary number of hostname-----------------*/
  struct addrinfo addrCriteria;
  memset(&addrCriteria, 0, sizeof(addrCriteria));
  addrCriteria.ai_family = AF_INET;
  addrCriteria.ai_socktype = SOCK_STREAM;
  addrCriteria.ai_protocol = IPPROTO_TCP;

  struct addrinfo *addrList;

  int rtnVal = getaddrinfo(serverIP, portNumber, &addrCriteria, &addrList);
  if (rtnVal != 0) {
    printf("getaddrinfo() failed\n");
    exit(1);
  }

  numericAddress = &((struct sockaddr_in *) (addrList->ai_addr))->sin_addr;
  /*Converting port to binary*/
  ((struct sockaddr_in *)(addrList->ai_addr))->sin_port = htons(servPort);
  /*----------------------------------------------------------------*/

  inet_ntop(addrList->ai_addr->sa_family, numericAddress, addrBuffer, sizeof(addrBuffer));
  printf("IP ADDRESS: %s\n", addrBuffer);

  /*Creating socket*/
  int sock = socket(AF_INET,SOCK_STREAM, IPPROTO_TCP);
  if (sock < 0) {
    printf("error creating socket\n");
    exit(1);
  }

  /*Establish connection to the echo server*/
  int r = connect(sock, addrList->ai_addr, addrList->ai_addrlen);
  if (r < 0) {
    perror("Connection failed\n");
    exit(1);
  }

  /*Reading from stdin and writing to socket until stdin ends
  bytes_read = read(0, buffer_stdin, sizeof(buffer_stdin));
  write(sock, buffer_stdin, bytes_read);*/

  while ((bytes_read = read(0, buffer_stdin, sizeof(buffer_stdin)-1)) > 0) {
    write(sock, buffer_stdin, bytes_read);
  }

  /*Shutting down write end of socket*/
  int r_shutdown = shutdown(sock, SHUT_WR);
  if (r_shutdown < 0) {
    printf("Shutting down write end of socket failed\n");
    exit(1);
  }

  /*Reading from socket and writing to stdout until socket ends*/
  while ((bytes_read = read(sock, buffer_stdout, sizeof(buffer_stdout)-1)) > 0) {
    write(1, buffer_stdout, bytes_read);
  }

  close(sock);
  exit(0);
}

我需要安装一些东西来连接到本地主机吗？

谢谢

编辑：好的，这是更新：

首先我在命令终端中输入：chmod a+x exe（其中 exe 是我们的 UDP 服务器） 然后我输入： ./exe 例如./exe 2525 然后我输入： echo "echo test" | ./本地主机

但是当这种情况发生时，终端不会返回“echo test”，它只是坐在那里，就像它正在等待用户的输入一样，或者就像它陷入无限循环一样。

Answer 1

看来您需要在命令行中提供本地主机：

./exe localhost 2525

或：

echo test | ./exe localhost 2525