is there enough information?
jeff at schwabcenter.com
Tue Feb 26 23:15:32 CET 2008
castironpi at gmail.com wrote:
> On Feb 26, 12:42 pm, Jeff Schwab <j... at schwabcenter.com> wrote:
>>>>> th1 th2
>>>>> set cmd
>>>>> run cmd
>>>>> get result
>>>>> continue continue
>>>>> th2 won't -run cmd- until th1 completes -set cmd-. th1 won't -get
>>>>> result- until th2 completes -run cmd-. and once -acknowledge-
>>>>> completes, both can go about their merry ways.
>>>> That is exactly the kind of case where semaphores are usually used.
>>>> Thread1 can "fill" the semaphore when the command is ready, then Thread2
>>>> can "empty" the semaphore once it has finished running the command.
> I want to awaken -that- -specific- -thread-.
> Semaphore acquire: "The implementation may pick one at random."
> Lock acquire: "which one of the waiting threads proceeds is not
> Event set: "All threads waiting for it to become true are awakened"
> Condition notify: "This method wakes up one of the threads waiting"
> Condition notifyAll: "Wake up all threads waiting on this condition"
> I will contend it's impossible without a specialization. Certainly an
> array of semaphores could fit the bill; is that what you were
A collection of semaphores could well be the right solution. Actually,
I'm getting the feeling that you want something like a Java Futures:
Does that sound promising?
More information about the Python-list