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Re: vxworks
It is close, but not entirely correct in 2004 or now. There are 5 states:
pending - blocked forever waiting on a system resource
delayed - blocked for a number of system ticks
pending & delayed - blocked for a maximum number of system ticks waiting on a system resource
ready - ready to run
running - of all the ready tasks, the one picked by the scheduling algorithm to run - note that vxworks schedules tasks (w/o regard to which RTP or the kernel where the task resides), not processes
in addition there is a suspended shadow state correlating to the pening/delayed/pending&delayed/ready states - in other words vxworks keeps track of what state a pending task would be in if you resumed it
the version of vxworks we run supports threads (called tasks in vxworks) and processes (called real-time processes) - the FIRST examples run entirely in multiple tasks inside the kernel, they do not use RTPs and I'm not sure they are enabled - so all the FIRST code runs inside the same memory context (thus the code we run can whack other tasks and the kernel itself so be careful!)
Hope this helps
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