Problem about libnet on FreeBSD 6.0

[prime]

On 12/31/05, Gilbert Fernandes <gilbert.fernandes at spamcop.net> wrote:
>
> > ----- Message from guomingyan at gmail.com ---------
> >     Date: Sat, 31 Dec 2005 20:55:38 +0800
> >     From: prime <guomingyan at gmail.com >
> > Reply-To: prime <guomingyan at gmail.com>
> >  Subject: Re: Problem about libnet on FreeBSD 6.0
> >       To: Gilbert Fernandes < gilbert.fernandes at spamcop.net>
> >
> > On 12/31/05, Gilbert Fernandes <gilbert.fernandes at spamcop.net> wrote:
> > >
> > > > I find that I can't include <net/ethernet.h> when I programming
> > > > with libnet,because $(CC) complains that "struct ether_addr
> > redefined".
> > > > But I need some definitions in <net/ethernet.h>,struct ether_header
> > etc.
> > > > Currently,I just copy the definitions I need from
> > <net/ethernet.h>,but
> > > > it seems very ugly.Any one has some good ideas?
> > >
> > > Could you show us the include line you use ?
> > >
> > > #include "blabla" and
> > > #include <blabla>
> > >
> > > will produce very different results as you know :)
> > >
> > > You do use #include <net/ethernet.h> ?
> > >
> > > --
> > > unzip ; strip ; touch ; grep ; finger ; mount ; fsck ; more ; yes ;
> > > fsck ; umount ; sleep
> > >
> > Here is my include lines,
> > #include ......
> > #include <net/ethernet.h>
> > #include <pcap.h>
> > #include <libnet.h>
> > ...........
> > and this is the error,
> > $(CC) said "/usr/local/include/./libnet/libnet-headers.h:393: error:
> > redefinition of `struct ether_addr'"
> >
> >
> > Thanks.
> > --
> > Three passions, simple but overwhelmingly strong, have governed my life:
>
> > the longing for love, the search for knowledge, and unbearable pity for
> > the suffering of mankind.
> >                          ---------Bertrand Russell
> >
> >
> > ----- End message from guomingyan at gmail.com -----
>
> Redefinition means that you have two declarations of the same
> function.
>
> One of the files you are including IS already including net/ethernet
> probably.
>
> Can you check ? :)
>
> --
> unzip ; strip ; touch ; grep ; finger ; mount ; fsck ; more ; yes ;
> fsck ; umount ; sleep
>

I can't agree more.Header files usually use "#ifndef XXX_H
 #define XXX_H
 .........
 #endif"
to avoid  being  included  more than once.<net/ethernet.h> is not different.
it use
"#ifndef _NET_ETHERNET_H_
 #define _NET_ETHERNET_H_
 ......
 #endif"
to avoid more than once include.

In my opinion,struct ether_addr is defined both in
<net/ethernet.h> and libnet-headers.h,and we need
include these two header files at the same time.

And here is my include lines

#include <stdio.h>
#include <stdlib.h>
#include <limits.h>
#include <errno.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <net/if_arp.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <net/ethernet.h>
#include <pcap.h>
#include <libnet.h>

--
Three passions, simple but overwhelmingly strong, have governed my life:
the longing for love, the search for knowledge, and unbearable pity for
the suffering of mankind.
                         ---------Bertrand Russell