Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cs.utexas.edu!asuvax!ncar!tank!mimsy!chris
From: chris@mimsy.umd.edu (Chris Torek)
Newsgroups: comp.unix.questions
Subject: Re: select()/stdio usage problem
Message-ID: <22256@mimsy.umd.edu>
Date: 3 Feb 90 01:14:56 GMT
References: <1988@castle.ed.ac.uk>
Organization: U of Maryland, Dept. of Computer Science, Coll. Pk., MD 20742
Lines: 19

In article <1988@castle.ed.ac.uk> ssj@castle.ed.ac.uk (S Johal) writes:
>  (1) Is it *totally* portable/POSIX compatible to use _cnt ?

No: there is no guarantee that a `FILE *' can be followed to a `_cnt' field,
and in my stdio, there is no _cnt field.  (There are two called _r and _w
that, collectively, mean what _cnt used to.)

>  (2) if not, Have I missed something in stdio.h that will let me
>      do what I'm after ?

No.  stdio has no multiplexing feature analagous to select().  If you
need select(), you cannot use stdio; if you need stdio, you cannot use
select().

If absolutely necessary, you are probably best off by defining a small
system-dependent module to do what select does but on multiple FILE objects.
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7163)
Domain:	chris@cs.umd.edu	Path:	uunet!mimsy!chris