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/*
* Copyright (C) 2008 The Android Open Source Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#define _GNU_SOURCE 1
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <stdio.h>
#include <sys/types.h>
#include <netdb.h>
int main( int argc, char** argv )
{
char* hostname = "localhost";
struct hostent* hent;
int i, ret;
if (argc > 1)
hostname = argv[1];
hent = gethostbyname(hostname);
if (hent == NULL) {
printf("gethostbyname(%s) returned NULL !!\n", hostname);
return 1;
}
printf( "gethostbyname(%s) returned:\n", hostname);
printf( " name: %s\n", hent->h_name );
printf( " aliases:" );
for (i = 0; hent->h_aliases[i] != NULL; i++)
printf( " %s", hent->h_aliases[i] );
printf( "\n" );
printf( " address type: " );
switch (hent->h_addrtype) {
case AF_INET: printf( "AF_INET\n"); break;
case AF_INET6: printf( "AF_INET6\n"); break;
default: printf("UNKNOWN (%d)\n", hent->h_addrtype);
}
printf( " address: " );
switch (hent->h_addrtype) {
case AF_INET:
{
const char* dot = "";
for (i = 0; i < hent->h_length; i++) {
printf("%s%d", dot, ((unsigned char*)hent->h_addr)[i]);
dot = ".";
}
}
break;
default:
for (i = 0; i < hent->h_length; i++) {
printf( "%02x", ((unsigned char*)hent->h_addr)[i] );
}
}
printf("\n");
return 0;
}
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