Re: spin lock

Krishna Myneni wrote:
Elizabeth D Rather wrote:
....
From your description, I gather that GRAB and RELEASE are equivalent to the spin
lock and unlock methods, while GET uses a scheduling scheme to grant access to
the resource and prevent one task from hogging the shared resource. It may be
that I have to implement something similar for my application as well.

When you say that tasks always PAUSE during I/O, is this the POSIX pause() function?

No, unless they coincidentally do the same things ;-) The SwiftOS multitasker (which technically is identical to the polyFORTH multitasker and generations before that) runs standalone (multitasking under Windows is quite different). It's basically a round-robin, with the rule that whenever a task initiates I/O it relinquishes the CPU and remains inactive (other tasks can run) until the I/O is complete. A task can also voluntarily pause any other time, e.g. during a CPU-intensive operation.

Cheers,
Elizabeth

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