NAME
mktimer — allocate a per-process timer
SYNOPSIS
#include <sys/timers.h>
timer_t mktimer(int clock_type, int notify_type, void *itimercbp);
DESCRIPTION
The
mktimer()
function is used to allocate a per-process timer
using the specified system-wide clock as the timing base.
mktimer()
returns an unique timer ID
of type
timer_t
used to identify the timer in timer requests (see
gettimer(3C)).
clock_type
specifies the system-wide clock
to be used as the timing base for the new timer.
notify_type
specifies the mechanism by which the process is to be notified
when the timer expires.
mktimer()
supports one per-process timer with a
clock_type
of
TIMEOFDAY
and
notify_type
of
DELIVERY_SIGNALS.
If
notify_type
is
DELIVERY_SIGNALS,
the system causes a
SIGALRM
signal to be sent to the process whenever the timer expires.
For
clock_type
TIMEOFDAY,
the machine-dependent clock resolution and maximum value are
1/
HZ
and
MAX_ALARM
seconds, respectively.
These constants are defined in
<sys/param.h>.
APPLICATION USAGE
mktimer()
is thread-safe. It is not async-cancel-safe.
RETURN VALUE
Upon successful completion,
mktimer()
returns a
timer_t,
which can be passed to the per_process timer calls.
If unsuccessful,
mktimer()
returns a value of
(timer_t)-1
and sets
errno
to indicate the error.
ERRORS
mktimer()
fails if any of the following conditions are encountered:
- [EAGAIN]
The calling process has already allocated
all of the timers it is allowed.
- [EINVAL]
clock_type
is not defined,
or does not allow the specified notification mechanism.
FILES
- /usr/include/sys/timers.h
- /usr/include/sys/param.h
STANDARDS CONFORMANCE
mktimer(): AES
