Date: Tue, 2 Feb 1999 11:41:48 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
X-Sender: eliz AT is
To: Nate Eldredge <nate AT cartsys DOT com>
cc: djgpp AT delorie DOT com
Subject: Re: Clarification of some errno values.
In-Reply-To: <36B6861A.64E0C306@cartsys.com>
Message-ID: <Pine.SUN.3.91.990202113528.13819T-100000@is>
MIME-Version: 1.0
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Reply-To: djgpp AT delorie DOT com


On Mon, 1 Feb 1999, Nate Eldredge wrote:

> Does DOS have per-process file limits?

Yes, it does.  Each DOS process has a so-called Job File Table (JFT) as 
part of its PSP, and when that table is filled, you cannot open any more 
files.  The size of the table is set to 20 when DOS creates the process.

But DJGPP detects the almost-full JFT situation before it actually
happens, and calls a DOS function which expands the JFT to the maximum
possible size under DOS (255 handles), so this limitation is meaningless
for DJGPP. 

AFAIK, DOS returns the same code (4) for both of these cases, anyway, so 
you will never see ENFILE in DJGPP programs, only EMFILE.  (ENFILE is 
mapped to a code returned by Novell in some obscure cases, but I doubt 
that error happens in real life).