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Re: What means of word 'quesue' in this RTOS description?

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On 2015-07-24, Tim Wescott <seemywebsite@myfooter.really> wrote:
>
>> I read an online tutorial on RTOS, see below dot line please.
>> I am not clear about what is for the word 'queue' in the first line.
>> Does it mean a task queue?
>
>> Thanks in advance.
>> ....................

>> The use of a queue allows the medium priority task to block until an
>> event causes data to be available - and then immediately jump to the
>> relevant function to handle the event. This prevents wasted processor
>> cycles - in contrast to the infinite loop implementation whereby an
>> event will only be processed once the loop cycles to the appropriate
>> handler.
>
> I'm not sure what you mean by "task queue".

I think that in this case your explanation below is correct.  In other
contexts, "task queue" might refer to a data structure internal to an
RTOS scheduler that defines an ordered set of the runnable tasks (the
order could be determined strictly by task priority or by some other
equitable-round-robin type scheme).  It's a queue that contains tasks
as its data elements.

> Generally, RTOS implementations don't bind a queue to any specific task.  
> Rather, the developer does so: anything can put messages into a queue, 
> anything can take messages off of a queue, and anything can pend on a 
> queue.  If the developer is wise, only one task takes things off the 
> queue, and there is a well-defined, small number (one is best) of sources 
> that put things on the queue.
>
> You arrange things so that the task that depends on the queue needs to 
> run if and only if there's a message on the queue, and you have the task 
> pend on the queue having a message available.

-- 
Grant Edwards               grant.b.edwards        Yow! Pardon me, but do you
                                  at               know what it means to be
                              gmail.com            TRULY ONE with your BOOTH!

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What means of word 'quesue' in this RTOS description? Robert Willy <rxjwg98@gmail.com> - 2015-07-24 04:12 -0700
  Re: What means of word 'quesue' in this RTOS description? Les Cargill <lcargill99@comcast.com> - 2015-07-24 07:47 -0500
  Re: What means of word 'quesue' in this RTOS description? Tim Wescott <seemywebsite@myfooter.really> - 2015-07-24 13:59 -0500
    Re: What means of word 'quesue' in this RTOS description? Grant Edwards <invalid@invalid.invalid> - 2015-07-24 19:34 +0000
    Re: What means of word 'quesue' in this RTOS description? Les Cargill <lcargill99@comcast.com> - 2015-07-24 20:52 -0500
      Re: What means of word 'quesue' in this RTOS description? Tim Wescott <seemywebsite@myfooter.really> - 2015-07-24 22:18 -0500
        Re: What means of word 'quesue' in this RTOS description? Les Cargill <lcargill99@comcast.com> - 2015-07-26 09:27 -0500
          Re: What means of word 'quesue' in this RTOS description? Don Y <this@is.not.me.com> - 2015-07-26 08:51 -0700
          Re: What means of word 'quesue' in this RTOS description? Tim Wescott <seemywebsite@myfooter.really> - 2015-07-26 16:23 -0500
    Re: What means of word 'quesue' in this RTOS description? upsidedown@downunder.com - 2015-07-25 08:57 +0300
  Re: What means of word 'quesue' in this RTOS description? Don Y <this@is.not.me.com> - 2015-07-24 12:34 -0700
    Re: What means of word 'quesue' in this RTOS description? Robert Willy <rxjwg98@gmail.com> - 2015-07-24 14:03 -0700
      Re: What means of word 'quesue' in this RTOS description? Don Y <this@is.not.me.com> - 2015-07-24 14:37 -0700

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