Comtrol eCos - Manual (Page 466)

Chapter 31. POSIX Standard Support
Notes
• Currently timer_getoverrun() only reports timer notifications that are delayed in the timer subsystem. If they
are delayed in the signal subsystem, due to signal masks for example, this is not counted as an overrun.
• The option CYGPKG_POSIX_TIMERS allows the timer support to be enabled or disabled, and causes
_POSIX_TIMERS to be defined appropriately. This will cause other parts of the POSIX system to have limited
functionality.
Message Passing [POSIX Section 15]
Functions Implemented
mqd_t mq_open( const char ∗ name, int oflag, ... );
int mq_close( mqd_t mqdes );
int mq_unlink( const char ∗ name );
int mq_send( mqd_t mqdes, const char ∗ msg_ptr,
size_t msg_len, unsigned int msg_prio );
ssize_t mq_receive( mqd_t mqdes, char ∗ msg_ptr,
size_t msg_len, unsigned int ∗ msg_prio );
int mq_setattr( mqd_t mqdes, const struct mq_attr ∗ mqstat,
struct mq_attr ∗ omqstat );
int mq_getattr( mqd_t mqdes, struct mq_attr ∗ mqstat );
int mq_notify( mqd_t mqdes, const struct sigevent ∗ notification );
From POSIX 1003.1d draft:
int mq_send( mqd_t mqdes, const char ∗ msg_ptr,
size_t msg_len, unsigned int msg_prio,
const struct timespec *abs_timeout );
ssize_t mq_receive( mqd_t mqdes, char ∗ msg_ptr,
size_t msg_len, unsigned int ∗ msg_prio,
const struct timespec *abs_timeout );
Functions Omitted
<none>
Notes
• The presence of message queues is controlled by the CYGPKG_POSIX_MQUEUES option. Setting this will
cause [_POSIX_MESSAGE_PASSING] to be defined and the message queue API to be made available.
• Message queues are not currently filesystem objects. They live in their own name and descriptor spaces.
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