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From: oster@well.sf.ca.us (David Phillip Oster)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Str255 in C
Message-ID: <22647@well.sf.ca.us>
Date: 15 Jan 91 09:21:07 GMT
References: <soDPV1w163w@cs.fau.edu> <1991Jan13.210327.9613@ux1.cso.uiuc.edu> <48035@apple.Apple.COM>
Organization: Whole Earth 'Lectronic Link, Sausalito, CA
Lines: 18

For safety, you shouldn't use strcpy on arbitrary pascal strings, since
ones read from resources won't have length bytes. I use:
/* StrMove - copy a pascal string from src to dest
	analagous to BlockMove()
 */
void StrMove(src, dest)Str255 src, dest;{
	BlockMove(src, dest, Length(src) + 1);
}

where Length(s) is defines as:
#define Length(s) ((short) (unsigned char) (s)[0])

so that I can be sure the length will be interpreted as a SIGNED integer
in the range 0..255. Without the casts, 0 - s[0] can return large positive
numbers, due to the nature of unsigned arithmetic in C.
-- 
-- David Phillip Oster - At least the government doesn't make death worse.
-- oster@well.sf.ca.us = {backbone}!well!oster