Re: linux headers and tcpdump programs

Alan Cox (
Thu, 11 Jul 1996 15:43:16 +0100 (BST)

> I would imagine
> net/udp.h to have something like:
> };
> #else
> struct udphdr {
> unsigned short source;
> unsigned short dest;
> unsigned short len;
> unsigned short check;
> };
> #endif


The Linux structures are defined in include/linux which is distributed with
the kernel. The others in include/net which is local. That seperation is
critical to stuff like cross compiling and porting.

The idea is that defining BSD source will let libc give you compatibility
defines, and POSIX source posix stuff (what is defined for posix anyway)