From:	"John M. Aldrich" <fighteer AT cs DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Text / binary implementation differences
Date:	Sun, 01 Feb 1998 19:02:13 -0500
Organization:	Two pounds of chaos and a pinch of salt.
Lines:	28
Message-ID:	<34D50D05.1493@cs.com>
References:	<Chameleon DOT 980201231642 DOT nrotem AT netvision DOT netvision>
NNTP-Posting-Host:	ppp203.cs.com
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To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Noam Rotem wrote:
> 
> Hi,
> 
> What is the difference, from the implementation side, between a text file and a binary
> one? Does djgpp mark EOF differently in a text file and a binary file? Is there any
> difference in the way the stream is buffered or treated? And, BTW, are stdin / stdout
> *text* streams? (I understand the logical differences between the two kinds, but not the
> actual compiler job around each one).

Text mode under DOS has two main differences from binary mode.  First,
the EOF character (Ctrl-Z) signals the end of the file in text mode. 
Second, MS-DOS text files signal EOL with a CR/LF pair.  When reading
such a file into memory, the extra LF is automatically stripped. 
Likewise, when writing a text file, EOF terminates the write, and CR's
are translated into CR/LF.

The moral of the story:  If you are writing text data, use text mode. 
If you are writing binary data, use binary mode.  Do NOT mix the two, or
your programs will almost certainly fail.

-- 
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|      John M. Aldrich       | "Animals can be driven crazy by pla- |
|       aka Fighteer I       | cing too many in too small a pen.    |
|   mailto:fighteer AT cs DOT com   | Homo sapiens is the only animal that |
| http://www.cs.com/fighteer | voluntarily does this to himself."   |
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