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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 desired task was suspended.
OS_ERR_TASK_SUSPEND_ISR
if If OS_CFG_CALLED_FROM_ISR_CHK_EN set to 1 in os_cfg.h: if the function is called from an ISR.
OS_ERR_TASK_SUSPEND_IDLE
if If attempting to suspend the idle task. This is not allowed since the idle task must always exist.
OS_ERR_TASK_SUSPEND_INT_HANDLER
if If attempting to suspend the ISR handler task. This is not allowed since the ISR handler task is a µC/OS-III internal task.
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