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Subject: Re: semaphores/shared memory
From: Tim Pierce <twpierce@bio-3.bsd.uchicago.edu>
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> 	essentially, I want the server to write a line of data to 
> shared memory, then signal all the clients at once that the data is
> there, so that they all pick up the data...

It sounds like this ought to be easy if you simply have each
client wait on the semaphore, and then have the server increment
the semaphore by a suitably high number (e.g. MAXINT) in order to
ensure that they all are freed at once.

Sort of a kluge, but it ought to work.