clock_nanosleep(3RT) Realtime Library Functions clock_nanosleep(3RT)NAMEclock_nanosleep - high resolution sleep with specifiable clock
SYNOPSIS
cc [ flag... ] file... -lrt [ library... ]
#include <time.h>
int clock_nanosleep(clockid_t clock_id, int flags, const struct time‐
spec *rqtp, struct timespec *rmtp);
DESCRIPTION
If the flag TIMER_ABSTIME is not set in the flags argument, the
clock_nanosleep() function causes the current thread to be suspended
from execution until either the time interval specified by the rqtp
argument has elapsed, or a signal is delivered to the calling thread
and its action is to invoke a signal-catching function, or the process
is terminated. The clock used to measure the time is the clock speci‐
fied by clock_id.
If the flag TIMER_ABSTIME is set in the flags argument, the
clock_nanosleep() function causes the current thread to be suspended
from execution until either the time value of the clock specified by
clock_id reaches the absolute time specified by the rqtp argument, or a
signal is delivered to the calling thread and its action is to invoke a
signal-catching function, or the process is terminated. If, at the time
of the call, the time value specified by rqtp is less than or equal to
the time value of the specified clock, then clock_nanosleep() returns
immediately and the calling process is not suspended.
The suspension time caused by this function can be longer than
requested because the argument value is rounded up to an integer multi‐
ple of the sleep resolution, or because of the scheduling of other
activity by the system. But, except for the case of being interrupted
by a signal, the suspension time for the relative clock_nanosleep()
function (that is, with the TIMER_ABSTIME flag not set) will not be
less than the time interval specified by rqtp, as measured by the cor‐
responding clock. The suspension for the absolute clock_nanosleep()
function (that is, with the TIMER_ABSTIME flag set) will be in effect
at least until the value of the corresponding clock reaches the abso‐
lute time specified by rqtp, except for the case of being interrupted
by a signal.
The use of the clock_nanosleep() function has no effect on the action
or blockage of any signal.
The clock_nanosleep() function fails if the clock_id argument refers to
the CPU-time clock of the calling thread. It is unspecified if clock_id
values of other CPU-time clocks are allowed.
RETURN VALUES
If the clock_nanosleep() function returns because the requested time
has elapsed, its return value is 0.
If the clock_nanosleep() function returns because it has been inter‐
rupted by a signal, it returns the corresponding error value. For the
relative clock_nanosleep() function, if the rmtp argument is non-null,
the timespec structure referenced by it is updated to contain the
amount of time remaining in the interval (the requested time minus the
time actually slept). If the rmtp argument is NULL, the remaining time
is not returned. The absolute clock_nanosleep() function has no effect
on the structure referenced by rmtp.
If clock_nanosleep() fails, it shall return the corresponding error
value.
ERRORS
The clock_nanosleep() function will fail if:
EINTR The clock_nanosleep() function was interrupted by a
signal.
EINVAL The rqtp argument specified a nanosecond value less
than zero or greater than or equal to 1,000 million; or
the TIMER_ABSTIME flag was specified in flags and the
rqtp argument is outside the range for the clock speci‐
fied by clock_id; or the clock_id argument does not
specify a known clock, or specifies the CPU-time clock
of the calling thread.
ENOTSUP The clock_id argument specifies a clock for which
clock_nanosleep() is not supported, such as a CPU-time
clock.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│Interface Stability │Standard │
├─────────────────────────────┼─────────────────────────────┤
│MT-Level │MT-Safe │
└─────────────────────────────┴─────────────────────────────┘
SEE ALSOclock_getres(3RT), nanosleep(3RT), pthread_cond_timedwait(3C),
sleep(3C), attributes(5), standards(5)SunOS 5.10 30 Jan 2004 clock_nanosleep(3RT)
