getaddrinfo函数

#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <netdb.h>
#include <sys/socket.h>
#include <arpa/inet.h>

int main(int argc, char * * argv)
{
    printf("sethostent函数执行：\n");
    sethostent(1);
    printf("-1.-1**************************************\n");
    struct hostent * host = NULL;
    host = gethostent();
    printf("h_name      =[%s]\n", host->h_name);
    printf("*h_aliases  =[%s]\n", *(host->h_aliases));
    printf("h_addrtype  =[%d]\n", host->h_addrtype);
    printf("h_length    =[%d]\n", host->h_length);
    printf("h_addr_list =[%s]\n", host->h_addr_list[0]);
    printf("h_addr      =[%s]\n", host->h_addr);

    struct sockaddr_in sin;
    bzero(&sin, sizeof(sin));
    bcopy(host->h_addr, &sin.sin_addr, host->h_length);
    char ipbuf[128];
    memset(ipbuf, 0, sizeof(ipbuf));
    inet_ntop(AF_INET, &sin.sin_addr.s_addr, ipbuf, sizeof(ipbuf));
    printf("主机名=[%s],IP地址=[%s]\n",host->h_name,ipbuf);

    bzero(&sin, sizeof(sin));
    memcpy(&sin.sin_addr, host->h_addr, host->h_length);
    memset(ipbuf, 0, sizeof(ipbuf));
    inet_ntop(AF_INET, &sin.sin_addr.s_addr, ipbuf, sizeof(ipbuf));
    printf("主机名=[%s],IP地址=[%s]\n",host->h_name,ipbuf);

    printf("setservent 函数执行：\n");
    setservent(1);
    printf("000000**************************************\n");
    struct servent * serv0 = NULL;
    serv0 = getservent();
    if(serv0 != NULL)
    {
        printf("s_name      =[%s]\n", serv0->s_name);
        printf("s_aliases[0]=[%s]\n", serv0->s_aliases[0]);
        printf("s_port     =[%d]\n", serv0->s_port);
        printf("s_proto     =[%d]\n", serv0->s_proto);
    }
    else
    {
        printf("serv0 is null\n");
    }

    printf("111111**************************************\n");

    struct addrinfo hint;
  hint.ai_flags = AI_CANONNAME; /* AI_CANONNAME | AI_NUMERICHOST | AI_NUMERICSERV */
  hint.ai_family = 0;
  hint.ai_socktype = 0;
  hint.ai_protocol = 0;
  hint.ai_addrlen = 0;
  hint.ai_addr = NULL;
  hint.ai_canonname = NULL;
  hint.ai_next = NULL;

    /*bzero( &hint, sizeof(struct addrinfo));*/

    printf("222222**************************************\n");
    struct addrinfo * result = NULL;
    printf("333333**************************************\n");
    /*getaddrinfo("wangxczj", NULL, &hint, &result);*/
    /*
    getaddrinfo(NULL, "tcpmux", &hint, &result);
    */
    getaddrinfo("YH.localdomain", NULL, &hint, &result);
    printf("result->ai_flags=[%d]\n", result->ai_flags);
    printf("result->ai_family=[%d]\n", result->ai_family);
    printf("result->ai_socktype=[%d]\n", result->ai_socktype);
    printf("result->ai_protocol=[%d]\n", result->ai_protocol);
    printf("result->ai_addrlen=[%d]\n", result->ai_addrlen);

    struct sockaddr_in seraddr;
    memset(&seraddr, 0, sizeof(seraddr));
    memcpy(&seraddr, result->ai_addr, result->ai_addrlen);
    memset(ipbuf, 0, sizeof(ipbuf));
    inet_ntop(AF_INET, &seraddr.sin_addr.s_addr, ipbuf, sizeof(ipbuf));
    printf("IP地址=[%s]\n", ipbuf);
    printf("PORT=[%s]\n", ntohs(seraddr.sin_port));

    printf("result->ai_canonname=[%s]\n", result->ai_canonname);
    if(result->ai_next == NULL)
    {
        printf("result->ai_next is null!\n");
    }
    else
    {
        printf("result->ai_next is not null!\n");
    }
    printf("444444**************************************\n");
    struct addrinfo * result2 = result->ai_next;
    printf("result2->ai_flags=[%d]\n", result2->ai_flags);
    printf("result2->ai_family=[%d]\n", result2->ai_family);
    printf("result2->ai_socktype=[%d]\n", result2->ai_socktype);
    printf("result2->ai_protocol=[%d]\n", result2->ai_protocol);
    printf("result2->ai_addrlen=[%d]\n", result2->ai_addrlen);

    struct sockaddr_in seraddr2;
    memset(&seraddr2, 0, sizeof(seraddr2));
    memcpy(&seraddr2, result2->ai_addr, result2->ai_addrlen);
    memset(ipbuf, 0, sizeof(ipbuf));
    inet_ntop(AF_INET, &seraddr2.sin_addr.s_addr, ipbuf, sizeof(ipbuf));
    printf("IP地址=[%s]\n", ipbuf);
    printf("PORT=[%s]\n", ntohs(seraddr2.sin_port));

    printf("result2->ai_canonname=[%s]\n", result2->ai_canonname);
    if(result2->ai_next == NULL)
    {
        printf("result2->ai_next is null!\n");
    }
    else
    {
        printf("result2->ai_next is not null!\n");
    }



    printf("555555**************************************\n");
    struct addrinfo * result3 = result2->ai_next;
    printf("result3->ai_flags=[%d]\n", result3->ai_flags);
    printf("result3->ai_family=[%d]\n", result3->ai_family);
    printf("result3->ai_socktype=[%d]\n", result3->ai_socktype);
    printf("result3->ai_protocol=[%d]\n", result3->ai_protocol);
    printf("result3->ai_addrlen=[%d]\n", result3->ai_addrlen);

    struct sockaddr_in seraddr3;
    memset(&seraddr3, 0, sizeof(seraddr3));
    memcpy(&seraddr3, result3->ai_addr, result3->ai_addrlen);
    memset(ipbuf, 0, sizeof(ipbuf));
    inet_ntop(AF_INET, &seraddr3.sin_addr.s_addr, ipbuf, sizeof(ipbuf));
    printf("IP地址=[%s]\n", ipbuf);
    printf("PORT=[%s]\n", ntohs(seraddr3.sin_port));

    printf("result3->ai_canonname=[%s]\n", result3->ai_canonname);
    if(result3->ai_next == NULL)
    {
        printf("result3->ai_next is null!\n");
    }
    else
    {
        printf("result3->ai_next is not null!\n");
    }


    printf("666666**************************************\n");
    struct addrinfo * result4 = result3->ai_next;
    printf("result4->ai_flags=[%d]\n", result4->ai_flags);
    printf("result4->ai_family=[%d]\n", result4->ai_family);
    printf("result4->ai_socktype=[%d]\n", result4->ai_socktype);
    printf("result4->ai_protocol=[%d]\n", result4->ai_protocol);
    printf("result4->ai_addrlen=[%d]\n", result4->ai_addrlen);

    struct sockaddr_in seraddr4;
    memset(&seraddr4, 0, sizeof(seraddr4));
    memcpy(&seraddr4, result4->ai_addr, result4->ai_addrlen);
    memset(ipbuf, 0, sizeof(ipbuf));
    inet_ntop(AF_INET, &seraddr4.sin_addr.s_addr, ipbuf, sizeof(ipbuf));
    printf("IP地址=[%s]\n", ipbuf);

    printf("result4->ai_canonname=[%s]\n", result4->ai_canonname);
    if(result4->ai_next == NULL)
    {
        printf("result4->ai_next is null!\n");
    }
    else
    {
        printf("result4->ai_next is not null!\n");
    }

    return 0;
}