Returns the current time.
#include <prtime.h> PRTime PR_Now(void);
PR_Now() returns the current time as number of microseconds since
the NSPR epoch, which is midnight (00:00:00) 1 January 1970 UTC.
You cannot assume that the values returned by
monotonically increasing because the system clock of the computer may be
reset. To obtain monotonically increasing time stamps suitable for
measuring elapsed time, use