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If OS_CFG_CALLED_FROM_ISR_CHK_EN set to 1 in DEF_ENABLED in os_cfg.h: if calling this function from an ISR
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If OS_CFG_ARG_CHK_EN is set to 1 in DEF_ENABLED in os_cfg.h: if p_q is a NULL pointer.
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If OS_CFG_OBJ_TYPE_CHK_EN is set to 1 in DEF_ENABLED in os_cfg.h: if you attempt to flush an object other than a message queue.
OS_ERR_OS_NOT_RUNNING
If OS_CFG_INVALID_OS_CALLS_CHK_EN is set to DEF_ENABLED in os_cfg.h: if µC/OS-III is not running yet.
Returned Value
The number of OS_MSG entries freed from the message queue. Note that the OS_MSG entries are returned to the free pool of OS_MSGs.
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OS_CFG_Q_EN and OS_CFG_Q_FLUSH_EN must be enabled in os_cfg.h. Refer to uCµC-OS-III Configuration Manual.
Callers
Application.
Notes/Warnings
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