Returns the value of interval timers.
Format
#include <time.h>
int getitimer (int which, struct itimerval *value);
1 – Arguments
which
The type of interval timer. The C RTL supports only
ITIMER_REAL.
value
Pointer to an itimerval structure whose members specify a timer
interval and the time left to the end of the interval.
2 – Description
The getitimer function returns the current value for the timer
specified by the which argument in the structure pointed to by
value.
A timer value is defined by the itimerval structure:
struct itimerval {
struct timeval it_interval;
struct timeval it_value;
};
The following table lists the values for the itimerval structure
members:
itimerval Member
Value Meaning
it_interval = 0 Disables a timer after its next expiration and
assumes it_value is nonzero.
it_interval = Specifies a value used in reloading it_value
nonzero when the timer expires.
it_value = 0 Disables a timer.
it_value = Indicates the time to the next timer
nonzero expiration.
Time values smaller than the resolution of the system clock are
rounded up to this resolution.
The C RTL provides each process with one interval timer,
defined in the <time.h> header file as ITIMER_REAL. This timer
decrements in real time and delivers a SIGALRM signal when the
timer expires.
3 – Return Values
0 Indicates success.
-1 Indicates an error; errno is set to EINVAL
(The value argument specified a time that was
too large to handle.)