Newsgroups: comp.os.msdos.djgpp
From: manfred DOT heumann AT uni-bielefeld DOT de (Manni Heumann)
Subject: Re: Problem with ostrstream object
References: <373d931a DOT 0 AT uni-wuerzburg DOT de>
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Date: Sun, 16 May 1999 11:54:31 GMT
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com

"Bernd König" <koenig AT physik DOT uni-wuerzburg DOT de> wrote:
>Hi,
>i found a problem with the ostrstream class (djgpp and gnu compiler under
>Win95). Somewhere in
>my program i have to create and remove an ostrstream object many times (i.e.
>endless). It looks
>like this:
>
>#include <iostream.h>
>#include <stdio.h>
>
>void main()
>{
>while(1){
>  {
>   ostrstream *wandler = new ostrstream;
>   wandler -> operator<<(10.0);
>   wandler -> str();
>   delete wandler;
>  }
>}
>}
>
>
>When running the program the system begins to swap until the error message:
>Virtual memory exceeded in 'new'. I suppose that the memory for the object
>is not realy released after deleting. Is it a bug in the c++ library or of
>Win95? I'm thankful for your help.
>
>B. Koenig
>

It's not a bug at all! When you call the member str(), your strstream gets 
frozen and the memory won't be released when you delete your object. You will 
either have to unfreeze the stream by calling wandler->freeze (0) or simply 
delete the array that str() returns (delete wandler->str()).

Btw: There is no need to create wandler dynamically with new as strstreams 
handle their memory themselves.

Manni