From: "Tom Demmer" <DEMMER AT brain1 DOT lstm DOT ruhr-uni-bochum DOT de>
Organization:  Lehrstuhl Stroemungsmechanik, RUB
To: Andy Maddison <maddison AT coventry DOT ac DOT uk>, djgpp AT delorie DOT com
Date:          Thu, 27 Nov 1997 08:14:24 GMT-1
Subject:       Re: Please Help! - file i/o
Reply-to: Demmer AT LStM DOT Ruhr-Uni-Bochum DOT De
Message-ID: <A20EAC24986@brain1.lstm.ruhr-uni-bochum.de>
Precedence: bulk

> Can anyone help me?
> 
> Program Fragment:  
> 
> unsigned char palette[768];  
> fstream inFile; 
> inFile.open("pal.dat",ios::binary);  
> inFile.seekg(0); //not essential
> inFile.read(palette,768);  
> inFile.close();  
> 
> This works fine using Borland C++, but under DJGPP the array (palette) is 
> always filled with zeros (NULLs?).  
> What is happening? Why doesn't it work?  
> I like using C++ and I don't want to have to switch to C style file i/o.
> 
Looks like you stumbled  over a damn bug in libiostream.
It opens the file in write mode, thus truncating it to length 0. 
The workaround is to say something like
 int fd = open("pal.dat",O_RDWR|O_BINARY);
 infile.open(fd);
 
Some comments on this bug:
I have answered this by now at least 3 times in the last two months, 
does this qualify for a FAQ ;-)

Seriously: Who ported libiostream to DJGPP? Not to blame him/her, just
to get an idea how much work that is. 
And, anybody working on that?

Ciao
Tom

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