Date:	Fri, 1 Nov 1996 18:01:30 -0500
Message-Id:	<199611012301.SAA14260@delorie.com>
From:	DJ Delorie <dj AT delorie DOT com>
To:	indrek AT warp DOT edu DOT ee
CC:	djgpp AT delorie DOT com
In-reply-to:	<Pine.LNX.3.91.961101194440.220A-100000@warp.edu.ee> (message
	from Indrek Mandre on Fri, 1 Nov 1996 21:06:13 +0200 (EET))
Subject:	Re: Problems with fread/fwrite

> > The bugs are not in DJGPP, but rather in some wrong assumptions you are
> > making about the way memory and file handling is done in C.
> 
> Yes, I'v never programmed on DOS, but I have correct assumptions.

You assume that text files and binary files are interchangeable.  ANSI
states that you may not make that assumption.

> Well, I have only 1 thing to say and think: DOS _is_ stupid.

No, DOS is *different*.  Both DOS and Unix are ANSI compliant, if you
pay attention to what ANSI states you may assume and not assume.

> I thougt that djgpp is like gcc. But now I know - djgpp is not gcc.

DJGPP *includes* gcc, it is not "like" gcc.  It uses gcc unmodified.
However, your problem has nothing to do with gcc, it has to do with
the C library, which is ANSI compliant.  Your program is NOT
compliant.

> Djgpp is stupid????

No, you are not programming according to the ANSI specs.

> Wrong! It's only because of the fopen/fread.

Since your data is uninitialized, it's likely that text/binary
conversions will take place, as it's likely that some of those
characters are newlines.

> I'm not using ANSI C. I think djgpp is _not_ ansi c.

You are not *writing* ANSI C, and DJGPP *is* ANSI C.  That is the
problem.  If you had been writing ANSI C, your program would have
worked.

> I'v reed only one book - Kerninghan-Ritchie's "The C programming
> language". My programming is based on that. There was no need to
> zero variables.

You should obtain the second edition to that book, which is based on
ANSI C instead of the obsolete K&R C.

There is no need to zero out global variables.  You must initialize
stack variables.  This is stated in the ANSI spec.

> I'm not so stupid. What are these text mode commands?

If you open the file with 'fopen(..., "r")', you have issued a
text-mode open, so all your fread/fwrite functions will be doing
text-mode I/O.

> > Try running under a debugger (gdb, edebug32, fsdb) and examine the contents
> > of those variables after you declare them.  You'll see what I mean.
> 
> Well, I was born using debugger :)

That would, according to DJGPP's history, make you less than five
years old :-)

> No, void main ( void ) is! I'm right. You are right. In gcc there is no
> difference, or is there? Explain me please. Nowhere is said what is correct. 

main() must return an integer return value, according to ANSI C.

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