View Full Version : Trying to understand locks

12-29-2009, 02:58 AM
I've been trying to get a a grasp on the concepts of LOCKS. The documentation is either deceptively simple or it's vague, I can't decide. I just need a someone who gets them to double check my understanding.

a) LOCKs don't actually prevent a resource from being used. They are just flags that a cog can set.
b) The actual area that actual resource that a lock protects is arbitrary, that is it is up to the programmer to decide.

So my understanding is that a lock is something like a bathroom door that can't be latched. The agreement is that if the door is closed it's in use. That doesn't stop someone from barging in, it's just a prearranged signal.

Is that about right?

Phil Pilgrim (PhiPi)
12-29-2009, 03:24 AM
Right on all counts.


12-29-2009, 03:28 AM
Thanks. The documentation makes it sound more complicated.

12-29-2009, 04:23 AM
Welcome to the forum http://forums.parallax.com/images/smilies/smile.gif

In most cases you won't need locks. I have never used them, nor have I seen code using them. So, if you are new to the prop, ignore them for now.

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· Search the Propeller forums (http://search.parallax.com/search?site=parallax&client=parallax&output=xml_no_dtd&proxystylesheet=parallax&proxycustom=<HOME/>&ie=&oe=&lr=)·(uses advanced Google search)
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12-29-2009, 05:31 AM
Love the "in use" analogy -- will have to make use of that in the PropBASIC documentation.