Subtle bug in fflush and fix

[Garry Wiegand]

In a recent article gwyn at brl.arpa (Doug Gwyn (VLD/VMB) <gwyn>) wrote:
>...
>The problems are not as well known as they should be.  Signals
>can impact the design of much of the C library.  AT&T reworked
>the standard I/O routines in an attempt to permit the use of
>printf() in a signal handler, but they didn't get it quite right
>because it is NOT POSSIBLE to get it right, at least not without
>severe performance impact...

I can see it would be tough to do at user level. But I don't see why 
the kernel read() and write() routines can't hang a simple queue on
their front ends. Elucidate, please?
-- 
garry wiegand   (garry%cadif-oak at cu-arpa.cs.cornell.edu)