Returns the value of NSPR's free-running interval timer.
Syntax
#include <prinrval.h> PRIntervalTime PR_IntervalNow(void);
Returns
A PRIntervalTime object.
Description
You can use the value returned by PR_IntervalNow() to establish epochs and to determine intervals (that is, compute the difference between two times). PR_IntervalNow() is both very efficient and nonblocking, so it is appropriate to use (for example) while holding a mutex.
The most common use for PR_IntervalNow() is to establish an epoch and test for the expiration of intervals. In this case, you typically call PR_IntervalNow() in a sequence that looks like this:
PRUint32 interval = ... ; // milliseconds
// ...
PRStatus rv;
PRIntervalTime epoch = PR_IntervalNow();
PR_Lock(data->mutex);
while (!EvaluateData(data)) /* wait until condition is met */
{
PRUint32 delta = PR_IntervalToMilliseconds(PR_IntervalNow() - epoch);
if (delta > interval) break; /* timeout */
rv = PR_Wait(data->condition, PR_MillisecondsToInterval(interval - delta));
if (PR_FAILURE == rv) break; /* likely an interrupt */
}
PR_Unlock(data->mutex);