Socket Programming Pointer Error

試著忘記壹切 提交于 2021-02-10 23:54:38

问题


I am trying to learn a bit of socket programming, I am also pretty new to c and having some trouble creating my server.

I am having trouble with pointers and the error I get when I try to run the code is

warning: passing 'int *' to parameter of type 'socklen_t *' (aka 'unsigned int *') converts between pointers to integer types with different sign [-Wpointer-sign]`

My server code is as follows, can anyone help with the error I am getting? Any other tips or comments are welcome as well

#include <sys/types.h>
#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>

int main( int argc, char *argv[] )
{
   int sockfd, newsockfd, portno, clilen;
   char buffer[256];
   struct sockaddr_in serv_addr, cli_addr;
   int  n;

   /* First call to socket() function */
   sockfd = socket(AF_INET, SOCK_STREAM, 0);

   if (sockfd < 0)
      {
      perror("ERROR opening socket");
      exit(1);
      }

   /* Initialize socket structure */
   bzero((char *) &serv_addr, sizeof(serv_addr));
   portno = 5001;

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

   /* Now bind the host address using bind() call.*/
   if (bind(sockfd, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0)
      {
      perror("ERROR on binding");
      exit(1);
      }

   /* Now start listening for the clients, here process will
   * go in sleep mode and will wait for the incoming connection
   */

   listen(sockfd,5);
   clilen = sizeof(cli_addr);

   /* Accept actual connection from the client */
   newsockfd = accept(sockfd, (struct sockaddr *)&cli_addr, &clilen);
   if (newsockfd < 0)
      {
      perror("ERROR on accept");
      exit(1);
      }

   /* If connection is established then start communicating */
   bzero(buffer,256);
   n = read( newsockfd,buffer,255 );

   if (n < 0)
      {
      perror("ERROR reading from socket");
      exit(1);
      }

   printf("Here is the message: %s\n",buffer);

   /* Write a response to the client */
   n = write(newsockfd,"I got your message",18);

   if (n < 0)
      {
      perror("ERROR writing to socket");
      exit(1);
      }

   return 0;
}

回答1:


Well, Actually you could mention to the the exact place of the error so we could look faster.

Anyway the error is in the accept call where you passed an int * instead of socklen_t *. in

 newsockfd = accept(sockfd, (struct sockaddr *)&cli_addr, &clilen);

So in this line:

int sockfd, newsockfd, portno, clilen;

change the declaration of clilen to

socklen_t clilen;

and it'll work.



来源:https://stackoverflow.com/questions/28550748/socket-programming-pointer-error

标签
易学教程内所有资源均来自网络或用户发布的内容,如有违反法律规定的内容欢迎反馈
该文章没有解决你所遇到的问题?点击提问,说说你的问题,让更多的人一起探讨吧!