In general, an option is built by a bitwise OR of the
desired option components. The set of valid options for the
rtems_message_queue_receive
directive are
listed in the following table:
RTEMS_WAIT
- task will wait for a message (default)
RTEMS_NO_WAIT
- task should not wait
An option listed as a default is not required to
appear in the option OR list, although it is a good programming
practice to specify default options. If all defaults are
desired, the option RTEMS_DEFAULT_OPTIONS
should
be specified on this call.
This example demonstrates the option parameter needed
to poll for a message to arrive. The option parameter passed to
the rtems_message_queue_receive
directive should
be RTEMS_NO_WAIT
.
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