the XENIX version is packed, and two bytes smaller than ours. So, define
the structure, and have it packed. I used the __attribte__((packed))
modifier for this; I could also have surrounded the struct definition with
#pragma pack(2) -- but that would have meant making ibcs2_timeb's definition
outside the function. This may need to be revisited if we ever want to
compile with a compiler other than gcc. (I also used 'unsigned long'
instead of 'time_t' because I am writing to match an external specification
-- and the definition of time_t could change.)
Reviewed by: Steven Wallace