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fame, had this to say about the shortcomings of the method: "a similar trick for interrupt-driven state machines that is too horrible to go into. I never thought it was an adequate general-purpose coroutine implementation because it’s not easy to have multiple simultaneous activations of a coroutine
96:, variables. An advantage is that they are very lightweight and therefore useful on severely memory constrained systems like small microcontrollers where other solutions are impractical or less desirable.
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and it’s not possible using this method to have coroutines give up control anywhere but in their top-level routine. A simple assembly-language stack-switching library lets you do both of those."
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eigenclass.org performed a comparison of protothreads against POSIX threads, and found a 400x improvement in speed
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so that successive calls to the same function will yield unless the guard conditional is true.
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Protothreads: Simplifying Event-Driven
Programming of Memory-Constrained Embedded Systems
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within a thread's function and an external variable used in within the
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A PDF with some in-depth discussion about the use of
Protothreads
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A feature of protothreads relative to other implementations of
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202:"Protothreads - Lightweight, Stackless Threads in C"
253:Using Protothreads for Sensor Node Programming
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187:"Brainwagon » Coroutines in C"
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120:Tom Duff
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163:SenSys
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