套接字编程，ipv6客户端程序不起作用

Question

Below is my code for IPv6 client program on local machine. When I run this program it just pauses like Reading Mode , not even printing "Start:". When I comment the line of socket() system call , then only it proceeds .

#include<stdio.h> 
#include<string.h>    
#include<sys/socket.h>
#include<arpa/inet.h> 
#include<unistd.h>
#include<errno.h>

int main( int argc, char *argv[])
{
    printf("Start:");
    int sock;
    char msg[20];
    struct sockaddr_in6 server;

    server.sin6_family=AF_INET6;
    server.sin6_port=htons(8888);
    inet_pton(AF_INET6, "127.0.0.1", &(server.sin6_addr) );


    sock=socket(AF_INET6, SOCK_STREAM , 0);
    if( sock == -1)
    {
     perror("Socket Creation Failed");
     return 1;
    }

    printf("Connecting");

   if( connect(sock, (struct sockaddr *)&server , sizeof(server)) < 0)
   {
    perror("Connection Failed");
    return 1;
   }

   if( read(sock, msg , sizeof(msg)) < 0)
   {
    perror("Reading Failed");
    return 1;
   }

   puts(msg);
   }

Answer 1

The problem was the inet_pton function . After passing the loopback address in IPv6 formate (0:0:0:0:0:0:0:1) , the program runs fine.

Answer 2

Your program is stuck at the blocking read(sock...). You need to add every where you have printf \\n to flush output to STDOUT to see output with printf!