int inaddr_cmp( const char * a, const char * b, const char * netmask, size_t nmemb )
{
size_t i;
for( i=0; i!=nmemb; ++i )
{
if( a[i] & netmask[i] > b[i] & netmask[i] )
return 1;
if( a[i] & netmask[i] < b[i] & netmask[i] )
return -1;
}
return 0;
}