From:	Erik Max Francis <max AT alcyone DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: NEED HELP with "_read()"
Date:	Sat, 07 Dec 1996 15:01:48 -0800
Organization:	Alcyone Systems
Lines:	34
Message-ID:	<32A9F75C.3BA286EE@alcyone.com>
References:	<58cqjf$6ie AT News DOT Dal DOT Ca>
NNTP-Posting-Host:	newton.alcyone.com
Mime-Version:	1.0
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Graham Howard Wile wrote:

>         In the "libc" documentation file, it tells how to use "_read()"
> by showing that you need to feed it these parameters:
> 
>                         size_t _read(int fildes, void *buf, size_t nbyte);
> 
>         The parameter I am having trouble with is the "int fildes". In
> the example in the file "libc" they write:
> 
>                         int r = read(0, buf, 10);

fildes stands for "file descriptor."  There are two traditional ways of
accessing streams in C:  through file descriptors, or through FILE pointers.
(Both end up being the same fundamental thing, obviously, but we're talking
at the interface level here.)

Whenever you make a call to an I/O function to manipulate the stream, you
need to pass in the file indicator -- whether or not it's a file descriptor
(an int) or a pointer to a FILE structure.

What's happening is that you're mixing and matching file descriptors and
FILE records.  You should be using fread (and the other f... functions), not
read.

Also, the first few file descriptors are reserved for streams which are
considered always open.  File descriptor 0 means stdin :-).

-- 
                             Erik Max Francis | max AT alcyone DOT com
                              Alcyone Systems | http://www.alcyone.com/max/
                         San Jose, California | 37 20 07 N 121 53 38 W
                                 &tSftDotIotE | R^4: the 4th R is respect
         "But since when can wounded eyes see | If we weren't who we were"

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