ANSI guru wanted ;)

After about 3 hours of investigating why my code doesn't work
on Linux when it works perfectly OK under NetBSD & Solaris I've found 
out it's Linux's rewind(3) behaviour, which is other than I expect.

Well, I have a stdio stream (created by tmpfile()). Data to the
underlying descriptor are written directly by write(2), then rewind(3)
is called and data are read via fread(). Until now I thought
rewind(3) does implicit lseek(2) every time. But it's definitely not true
under Linux.

What ANSI spec says ? Should rewind(3) work even when
stdio functions are bypassed and data are written to descriptor directly ?

Anyway, I praise BSDs for taking safe approach. And I'd like to know
if Linux's approach is broken or the behaviour is unspecified.

-- 
Jaromir Dolecek <dolecek@ics.muni.cz>	http://www.ics.muni.cz/~dolecek/
-------------------------------------------------------------------------
It is better never to have been born.  But who among us has such luck?
One in a million, perhaps.