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From: cjmchale@cs.tcd.ie (Ciaran McHale)
Newsgroups: comp.object
Subject: Re: concurrency control
Message-ID: <1991Apr5.171136.13476@cs.tcd.ie>
Date: 5 Apr 91 17:11:36 GMT
Article-I.D.: cs.1991Apr5.171136.13476
References: <1991Apr4.215238.14067@bingvaxu.cc.binghamton.edu>
Organization: DSG, Dept. of Comp. Sci., Trinity College, Dublin.
Lines: 33


In <1991Apr4.215238.14067@bingvaxu.cc.binghamton.edu>
yunyau@bingvaxu.cc.binghamton.edu (Yun Yau Shih) writes:

>I am new to the object-oriented concept. So, I hope I would not insult
>any one in this group by asking the following question.

>What does it mean by "Several threads can simultaneously enter an object
>and execute concurrently." Does it mean REAL CONCURRENCY?

Yes, that's basically what it means. Perhaps there won't be "real"
concurrency is there is only one processor and several threads, but the
principle is the same regardless of whether the concurrency is "real" or
"pseudo."

>How about the
>concurrency control, then? Or an object should have a machanism like a
>monitor. Any comment/hint/reference is welcomed. Thanks in advance.

Yes, the object should be able to ensure its own consistency if several
threads/activities/processes/whatever-you-call-them are executing in it
concurrently. As for references to this ... well it just so happens that
that's the area of my research. (No doubt this will surprise many people
on comp.window.x and soc.motss:-) I'll post some references in a few
minutes.


Ciaran.
-- 
Ciaran McHale           "There's a lot to be said for verbosity."     ----
Department of Computer Science, Trinity College, Dublin 2, Ireland.   \  /
Telephone: +353-1-772941 ext 1538       FAX: +353-1-772204             \/
Telex: 93782 TCD EI                     email: cjmchale@cs.tcd.ie