Get the clock attribute from a condition-variable attribute object
#include <pthread.h> int pthread_condattr_getclock( const pthread_condattr_t * attr, clockid_t * id );
- A pointer to the pthread_condattr_t object from which you want to get the clock.
- A pointer to a clockid_t object where the function can store the clock ID.
Use the -l c option to qcc to link against this library. This library is usually included automatically.
The pthread_condattr_getclock() function obtains the value of the clock attribute from the attributes object referenced by attr.
The clock attribute is the clock ID of the clock that's used to measure the timeout service of pthread_cond_timedwait(); one of:
- CLOCK_REALTIME — the standard POSIX-defined clock. Timers based on this clock wake up the processor if it's in a power-saving mode.
- CLOCK_SOFTTIME — this clock is active only when
the processor isn't in a power-saving mode.
For example, an application using a CLOCK_SOFTTIME timer
to sleep wouldn't wake up
the processor when the application was due to wake up.
This will allow the processor to enter a power-saving mode.
While the processor isn't in a power-saving mode, CLOCK_SOFTTIME behaves the same as CLOCK_REALTIME.
- CLOCK_MONOTONIC — this clock always increases at a constant rate and can't be adjusted.
The default value of the clock attribute refers to the system clock.
- Invalid value attr.