Date: Wed, 18 Jun 1997 08:48:21 -0400 (EDT)
Message-Id: <199706181248.IAA04330@delorie.com>
From: DJ Delorie <dj AT delorie DOT com>
To: eliz AT is DOT elta DOT co DOT il
CC: eldredge AT ap DOT net, djgpp AT delorie DOT com
In-reply-to: <Pine.SUN.3.91.970618091650.23726A-100000@is> (message from Eli
	Zaretskii on Wed, 18 Jun 1997 09:17:46 +0300 (IDT))
Subject: Re: Possible misbehavior of write
Precedence: bulk


> I don't have POSIX handy (ANSI doesn't know about EFAULS or SIGSEGV,
> and `write' is non-ANSI anyway, so ANSI is irrelevant), therefore I
> don't know what's POSIX policy on these.  DJ?

POSIX is pretty vague about EFAULT because, as it claims, "not all
systems can reliably detect it."

Here are some relevent sections:

2.4 Error Numbers

  [EFAULT]	Bad Address

	The system detected an invalid address in attempting to use an
	argument of a call.  The reliable detection of this error is
	implementation defined; however, implementations that do
	detect this condition shall use this value.

6.4.2 Write to a File

  EFAULT is not mentioned.  It does, however, state that if the count
  is zero, write() shall return zero and have no other results.

B.2.4 Error Numbers (Informative)

  Some error numbers, such as [EFAULT], are entirely implementation
  defined and are noted as such in their description in 2.4.