56 lines
1.2 KiB
C
56 lines
1.2 KiB
C
#include <stdio.h>
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#include <errno.h>
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#include <sys/types.h>
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#include <sys/socket.h>
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#include <sys/ioctl.h>
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#include <net/if.h>
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#include <netinet/in.h>
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/*
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* open a socket, get the process group information of the socket, and use the
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* socket to get the network interface configuration list
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*/
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main()
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{
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int sock;
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int ioctl_result;
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/* get a socket */
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sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
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if (sock < 0)
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{
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perror("Cannot create socket");
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exit(1);
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}
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/* use ioctl() to get the process group information */
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{
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int get_process_group;
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ioctl_result = ioctl(sock, SIOCGPGRP, (char *) &get_process_group);
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if (ioctl_result < 0)
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{
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int my_errno = errno;
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fprintf(stderr, "errno %d ", my_errno);
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perror("ioctl(get process group)");
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}
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}
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/* use ioctl() to get the interface configuration list */
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{
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static struct ifconf ifc; /* init to 0 */
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ioctl_result = ioctl(sock, SIOCGIFCONF, (char *) &ifc);
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if (ioctl_result < 0)
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{
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int my_errno = errno;
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fprintf(stderr, "errno %d ", my_errno);
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perror("ioctl(get interface configuration list)");
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}
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}
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}
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