From: nikki AT gameboutique DOT co (nikki)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Char/unsigned/unsigned char conversion problems.
Date: 17 Feb 1997 21:48:11 GMT
Organization: GameBoutique Ltd.
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> I was assuming that the upper byte would be zeroed in the conversion (unsigned)Ch.
> I.E.
> char : 10110011 -----> unsigned : 0000000010110011
> 
> Is this assumption wrong and the upper byte could be anything?

i didn't understand most of this as it was in c++ but that part above is
wrong.

char is by default signed, so having the higher bit set as 1 like that will
be treated as a negative number. then you try to convert a negative number
into an unsigned short. actually i'm not sure what that will do, it might
append leading 1's instead of 0's as you expect, i always avoid those sort
of problems by ensuring i have an unsigned char in the first place before
conversion :)

regards,
nik


-- 
Graham Tootell           
nikki AT gameboutique DOT com