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From: dcm@baldur.dell.com (Dave McCracken)
Newsgroups: comp.os.mach
Subject: Re: Wish explanation of some cthread calls
Message-ID: <4438@dell.dell.com>
Date: 28 Nov 89 13:53:39 GMT
References: <4ZQVTxC00hYP4whmM2@cs.cmu.edu> <113980001@hpcvlx.cv.hp.com> <113980003@hpcvlx.cv.hp.com>,
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> 
> This is a pretty general problem.  For example, a task has only one
> notify port, and if different libraries try to receive notifications
> from it they will interfere with each other.

This problem has been solved in the 1003.4 (POSIX) pthreads proposal.
This proposal is very similar to cthreads, but the cthread_set_data
and cthread_data calls have been expanded to include a key.  There is
a call to create the key, which would be made by the initial thread,
then all subsequent references by any thread would use it.

The metaphor for this is a two-dimensional array, with one dimension
the key (the library making the call), and the other dimension the
thread id.

Dave McCracken					Dell Computer
dcm@dell.dell.com				9505 Arboretum Blvd
(512) 343-3720					Austin, TX 78759-7299