Re: problem with binary file

From: Floyd L. Davidson (floyd_at_apaflo.com)
Date: 08/13/05 

Date: Sat, 13 Aug 2005 12:56:13 -0800

"Peter T. Breuer" <ptb@oboe.it.uc3m.es> wrote:
>Reinardt Behm <reinhardt.behm@t-online.de> wrote:
>> > EOF is -1 which is just a character like any other (255 usually). You
>> > should read untl EOF is _signalled_ from your reader method, not until
>> > it is _read_.
>>
>> This is nonsense. EOF is not a _char_ it is an _int_
>
>Nonsense. Chars are (very short ints). Even shorter than shorts.

Nonsense! EOF is *not* a "just a character", is not data, and
is never 255.

It is a flag returned by the read(2) function, indicating that
an attempt has been made to read past the end of the file.

>> (value 0xffff if int is
>> 16 bit) and you should always read ints from a file to be able to detect
>> EOF.

EOF is not a 16 bit int either. It is a *flag*, and on 32 bit
systems is 32 bits wide, on 64 bit systems is 64 bits wide,
etc. etc.

>You don't seem to understand. EOF will be SIGNALLED, not read. The
>reason why his placing a -1 (char) in the file does not stop the method
>reading beyond the CHAR is because it is a byte like any other.

That is correct. (Which begs the question of why you said it
was 255, usually?) 

-- 
Floyd L. Davidson            <http://www.apaflo.com/floyd_davidson>
Ukpeagvik (Barrow, Alaska)                         floyd@apaflo.com

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