Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.1 6/24/83; site ki4pv.UUCP
Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxt!houxm!vax135!petsd!peora!ucf-cs!ki4pv!tanner
From: tanner@ki4pv.UUCP (Tanner Andrews)
Newsgroups: net.unix-wizards
Subject: Re: how safe is it to read/write with fopen'ed files?
Message-ID: <444@ki4pv.UUCP>
Date: Wed, 28-Aug-85 12:17:20 EDT
Article-I.D.: ki4pv.444
Posted: Wed Aug 28 12:17:20 1985
Date-Received: Sat, 31-Aug-85 08:34:16 EDT
References: <4983@allegra.UUCP>
Organization: CompuData South, DeLand
Lines: 17

] note referenced asks how safe it is to use read(2) with files
] opened using fopen(3)

If you do not extract the file descriptor from the fp structure
returned by fopen(2), many systems won't like it.  The pointer value
from fopen(3) is not likely to make a good fd.

If you do extract the fd, chances are reasonably good that it will
work.  Of course, you must either (a) not be buffering your i/o,
or (b) flush your buffers before you use read(2)/write(2).

As good form you do well not to intermix section 2 i/o calls and
section 3 i/o calls on the same file.  Consider using open(2).

-- 
<std dsclm, copies upon request>	   Tanner Andrews, KI4PV
uucp:					...!decvax!ucf-cs!ki4pv!tanner