/*********************************************************************************
 *      Copyright:  (C) 2018 NULL
 *                  All rights reserved.
 *
 *       Filename:  get.c
 *    Description:  This file 
 *                 
 *        Version:  1.0.0(01/24/2018)
 *         Author:  zhaowenbin <
 
[email protected]>
 *      ChangeLog:  1, Release initial version on "01/24/2018 06:17:24 PM"
 *                 
 ********************************************************************************/
#include <stdio.h>
#include <unistd.h>
#include <string.h>

int get_nic_ipaddr(char *nic,char *ip,char *netmask);

int main(int argv,char **argc)
{
    char net[30];
    char ip[32];
    char netmask[32];
    memset(net,0,sizeof(net));
    printf("please enter netcommand:\n");
    gets(net);
    get_nic_ipaddr(net,ip,netmask);

    return 0;

}


int get_nic_ipaddr(char *nic,char *ip,char *netmask)
{
    FILE *fp;
    char buf[512];
    char *stream1,*stream2;
    int num=0;
    printf("commander:%s\n",nic);
    fp=popen(nic,"r"); 
    printf("commander:%s\n",nic);
    //stream1=strstr(fp,"addr:");
    //stream2=strstr(fp,"Bcast");
    //printf("%p\n",stream1);
    while(fgets(buf,sizeof(buf),fp))
    {
       if(strstr(buf,"inet addr:"))
       {
        stream1=strstr(buf,"inet addr:");
        //printf("%p\n",stream1);
       }
       if(strstr(buf,"Bcast:"))
       {
        stream2=strstr(buf,"Bcast");
        //printf("%p\n",stream2);
        snprintf(ip,stream2-stream1,stream1);
        printf("%s\n",ip);
        stream1=0;
        stream2=0;
       }
       if(stream1==0)
       {

         if(strstr(buf,"Mask:"))
         {
            stream1=strstr(buf,"Mask:");
            //printf("%p\n",stream1);
            printf("%s",stream1);
         }
       }

       
       if(stream2==0)
       {
           if(strstr(buf,"inet6 addr:"))
           {
            stream2=strstr(buf,"inet6 addr:");
            //printf("%p\n",stream2);
            //snprintf(netmask,stream2-stream1,stream1);
            //printf("%s",netmask);
            stream1=0;
            stream2=0;
           }
       }
    }

    close(fp);
}
 

[[email protected] 2018125]$ ./a.out 
please enter netcommand:
ifconfig eth1
commander:ifconfig eth1
commander:ifconfig eth1
eth1: error fetching interface information: Device not found
[[email protected] 2018125]$ ./a.out 
please enter netcommand:
ifconfig eth0
commander:ifconfig eth0
commander:ifconfig eth0
inet addr:192.168.138.128 
Mask:255.255.255.0