Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!cs.utexas.edu!sun-barr!sun!pepper!cmcmanis
From: cmcmanis%pepper@Sun.COM (Chuck McManis)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Locking & forbiding
Message-ID: <108749@sun.Eng.Sun.COM>
Date: 8 Jun 89 01:02:07 GMT
References: <7cBq029532iy01@amdahl.uts.amdahl.com> <108333@sun.Eng.Sun.COM> <d2YG02GD32Hm01@amdahl.uts.amdahl.com>
Sender: news@sun.Eng.Sun.COM
Reply-To: cmcmanis@sun.UUCP (Chuck McManis)
Organization: Sun Microsystems, Mountain View
Lines: 43

I wrote : 
>Why don't you use SetWindowTitle()?

In article <d2YG02GD32Hm01@amdahl.uts.amdahl.com> (Dave Lowrey) writes:
>I need to get the address of the current title, as well as
>setting a new title.
>
>So I guess I am asking if it is safe to access this info
>without any locking.

Hmmmm, why do I get the feeling that you aren't doing something that 
one my consider "normal" programming practice? :-) 

So to be completely blunt and open about this :

	You opened a window, so you have a pointer to the window. You 
	can use SetWindowTitles() to change it to whatever you want.
	No locking required because you are the only one who will be
	playing with your window title.  Further you could cache 
	Window->Title before you set the title so that you restore 
	the title that you originally had on the window, or of course 
	you could just use the same pointer that you gave in the 
	NewWindow structure. 

	There is of course the "hack" case, which is to say you have
	a pointer to a window that you did not open and do not own.
	In which case you have absolutely no business at all mucking
	with it's title because there is no locking mechanisim in the
	world that can protect you from the application who actually
	owns the window and might do any arbitrarily legal thing, like
	substituting the title and calling FreeMem() on the pointer 
	that was in there. And if you had stuffed in some bogus title
	the Application will have quite legally freed your memory for
	you and you and it both will probably crash.  

By the way, I couldn't find any reference in IntuitionBase that had
to do with titles anyway. Where were you looking?


--Chuck McManis
uucp: {anywhere}!sun!cmcmanis   BIX: cmcmanis  ARPAnet: cmcmanis@sun.com
These opinions are my own and no one elses, but you knew that didn't you.
"A most excellent barbarian ... Genghis Kahn!"