Path: utzoo!utgpu!attcan!uunet!ncrlnk!ncr-sd!hp-sdd!hplabs!hpl-opus!hpccc!hp-ses!hpcea!hpausla!jcl
From: jcl@hpausla.HP.COM (Jeff Laing)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Re: A plea for help (double-clicking disabled in Finder...)
Message-ID: <2580011@hpausla.HP.COM>
Date: 23 Jan 89 22:20:08 GMT
References: <379@lclark.UUCP>
Organization: HP Australian Software Operation
Lines: 31

In article <379@lclark.UUCP>, dan@lclark.UUCP (Dan Revel) writes...
> Chernicoff's program has several bugs in it, and this is a manifestation
> of one of them.  I think he sets the event mask (filtering out mouseUp ?)

One of the saddest realizations I had was that even Chernicoff's code had
bugs in it; I found it out the easy way, by reading it in as I typed it (yes,
I had to type from the book).  Its also amazing how much other source code
I have seen floating around that has the same problem.  So, in the interest
of letting someone else avoid a problem that 'nearly' got me.

You really need to watch those handles being locked and unlocked a lot. The
number of times I have seen ...

a()
{	
	HLock(h);
	b(h);
	*h->x = ...	/* this would no survive a heap scramble */
	HUnlock(h);
}

b(h)
Handle h;
{
	HLock(h);
	...
	HUnlock(h);
}

(Yeh, yeh, Chernicoff was in pascal.  But I'm in C-mode at the moment and you
get my point anyway ...)