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is a pointer to a variable that will contain an error code returned by this function.
OS_ERR_NONE
if If the call was successful and the function returned the next available task register ID (or index).
OS_ERR_NO_MORE_ID_AVAIL
if If you already called OSTaskRegGetID() OS_CFG_TASK_REG_TBL_SIZE (see os_cfg.h) times and thus there are no more IDs available to be assigned.
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