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Task local variables

Posted by Peter Nielsen on November 24, 2008

My question:
if i use a lot of local variables in a taskA - i.e. some of them are in CPU registers and some are put on the stack (thats how memory normally are allocated).

Now a higher priority taskB preemtives taskA and do some job and returns control to taskA.

When taskA runs again are all local variables valid or do i have to declare them static - i asume them in Cpu regs. are restored but what about the local vars. which where stored on the stack in taskA ???????

RE: Task local variables

Posted by Jesper Matthiesen on November 24, 2008
yes, all registers are saved on the stack before a context switch and restored afterwards, so your vars will be intact..

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