From: broeker AT acp3bf DOT knirsch DOT de (Hans-Bernhard Broeker)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: 64 bit integer, putc and double.
Date: 9 Sep 1999 17:26:50 +0200
Organization: RWTH Aachen, III. physikalisches Institut B
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Tom Morton (tmorton AT yikesstation DOT freeserve DOT co DOT uk) wrote:
> I have 2 questions:

> 1. Does djgpp support 64-bit integers?

Yes. GCC supports 'long long int' as a way to access 64bit integers,
on 32bit machines.

> 2. I need to store float and double variables in a binary savegame file.
> How is this done using getc/putc. 

It is done *not* using getc/putc. There are *much* simpler ways to do
it.

> My plan is to shove the address of
> the float into a long integer pointer and then write the float to the
> file as if it is an 32-bit integer. 
[...]

You're thinking about it in an overly complicated way. Just open your
C textbook (or the DJGPP libc manual, 'info libc') and look up
functions 'fwrite' and 'fread'. In a nutshell:

	#include <stdio.h>

	double myDouble;
	int myInt;
	FILE *myFile = fopen("filename", "wb");

	fwrite (&myDouble, sizeof(double), 1, myFile);
	fwrite (&myInt, sizeof(int), 1, myFile);

	fclose (myFile);

Caveat: if there is any chance your program will ever be ported/used
on any other type of computer, try *not* to use raw binary file
I/O. That type of file is not portable from one architecture to an
other, and you had better avoid it, thus.
-- 
Hans-Bernhard Broeker (broeker AT physik DOT rwth-aachen DOT de)
Even if all the snow were burnt, ashes would remain.