fread, fwrite with size 0

[hombre <hombre67@gmx.at>]

Hello,

I think that fread and fwrite does not return 0 when parameter size is 0 
(when nmemb is 0, it does).
Clib spec says: If size or nmemb is zero, fread/fwrite returns zero

I did the following changes to make it work:

fread:
from
     return nmemb;
to
     return len == 0 ? 0 : nmemb;

fwrite:
from
     return k == l ? nmemb : k / size;
to
     if (l == 0)
         return 0;
     else
         return k == l ? nmemb : k / size;

Regards,
Erwin