[wellylug] Using Diff

[Edouard Chalaron]

Hi
I have to use Diff to debug a pice of soft. Nothing too difficult (well.... I 
thught so !!!)

Could anyone teach me how to properly use diff ? The diff --help is a bit 
elliptic to me.  
here is the upgrade I have to do.... thanks a lot 
Edouard
***********************

>   diff  fontsel.cc.~1~  fontsel.cc
> 18,19c18,42
> < #include <hash_map>
> < using std::hash_map;
> ---
>  > // #include <hash_map>
>  > // using std::hash_map;
>  >
>  >
>  > #if (__GNUC__<3)
>  > # include <hash_map>
>  >   namespace Sgi
>  > {
>  >     using ::hash_map;
>  > };
>  >
>  > // inherit globals
>  > #else
>  > # include <ext/hash_map>
>  > # if __GNUC_MINOR__ == 0
>  >    namespace Sgi = std;
>  > // GCC 3.0
>  > # else
>  >    namespace Sgi = ::__gnu_cxx;
>  > // GCC 3.1 and later
>  > # endif
>  > #endif
>  >
>  > using namespace Sgi;