From:	Erik Max Francis <max AT alcyone DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Minor problem with operator new[]
Date:	Tue, 03 Dec 1996 20:01:14 -0800
Organization:	Alcyone Systems
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Message-ID:	<32A4F78A.494BAE74@alcyone.com>
References:	<5800sc$5jp AT ns2 DOT southeast DOT net>
NNTP-Posting-Host:	newton.alcyone.com
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To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

M. Edward Kiser wrote:

> Recently, just out of curiosity, I decided to see how much memory I
> could allocate under various conditions. I wrote this program to find
> out, based on the assumption that operator new[] would throw an
> exception if it couldn't allocate the memory. But it doesn't throw the
> exception. It prints a message
> 
> "Virtual memory exceeded in new"
> 
> and terminates the program. This is very un-ANSI-like!

As far as I can tell, this is not _quite_ draft standard C++ behavior (note
there is no ANSI C++ standard as of yet), but is acceptable.  Get a good
book on C++ and look up set_new_handler.  Basically, the default behavior
of operator new should be to return the null pointer when unable to
allocate memory.  However, and this is usually the case, a new_handler is
created (via set_new_handler) to automatically terminate the program.
(Most implementations do this -- I'm not sure if they are strictly draft
standard conforming.)

Bottom line, though, is that operator new does _not_ throw an exception on
failure.  (Certainly as far as I can see in my reference books here.)

-- 
                             Erik Max Francis | max AT alcyone DOT com
                              Alcyone Systems | http://www.alcyone.com/max/
                         San Jose, California | 37 20 07 N 121 53 38 W
                                 &tSftDotIotE | R^4: the 4th R is respect
         "But since when can wounded eyes see | If we weren't who we were"

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