Comtrol eCos - Manual (Page 402)

Chapter 18. Device Driver Interface to the Kernel
cyg_drv_cond_wait
Function:
void cyg_drv_cond_wait( cyg_drv_cond *cond )
Arguments:
cond - condition variable to wait on
Result:
None
Level:
Thread
Description:
Wait for a signal on the condition variable pointed to by the cond argument. The thread must have locked
the associated mutex, supplied in cyg_drv_cond_init() , before waiting on this condition variable. While
the thread waits, the mutex will be unlocked, and will be re-locked before this function returns. It is
possible for threads waiting on a condition variable to occasionally wake up spuriously. For this reason it
is necessary to use this function in a loop that re-tests the condition each time it returns. Note that this
function performs an implicit scheduler unlock/relock sequence, so that it may be used within an explicit
cyg_drv_dsr_lock()...cyg_drv_dsr_unlock() structure.
cyg_drv_cond_signal
Function:
void cyg_drv_cond_signal( cyg_drv_cond *cond )
Arguments:
cond - condition variable to signal
Result:
None
Level:
DSR
Description:
Signal the condition variable pointed to by the cond argument. If there are any threads waiting on this variable
at least one of them will be awakened. Note that in some configurations there may not be any difference
between this function and
cyg_drv_cond_broadcast() .
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