.\"	$NetBSD: timer_create.2,v 1.13 2017/07/03 21:32:50 wiz Exp $
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.\" by Christos Zoulas.
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.Dd May 19, 2010
.Dt TIMER_CREATE 2
.Os
.Sh NAME
.Nm timer_create
.Nd create a per-process timer
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In time.h
.In signal.h
.Ft int
.Fn timer_create "clockid_t clockid" "struct sigevent * restrict evp" "timer_t * restrict timerid"
.Sh DESCRIPTION
The
.Fn timer_create
function creates a per-process timer using the clock specified in the
.Ar clockid
argument.
If it succeeds, the
.Fn timer_create
function fills in the
.Ar timerid
argument with an id associated with the timer created that can be used by
other timer related calls.
The
.Ar clockid
must be a valid clock id as defined in
.In time.h .
The timer is created in a disarmed state.
.Pp
An optional
.Pq non- Ns Dv NULL
.Em struct sigevent
argument can be specified by the
.Ar evp
argument.
If the
.Ar evp
argument is
.Dv NULL ,
then
.Fa evp->sigev_notify
defaults to
.Dv SIGEV_SIGNAL
and
.Fa evp->sigev_value
is set to
.Ar timerid .
Refer to
.Xr sigevent 3
for more details.
.Sh NOTES
Timers are not inherited after a
.Xr fork 2
and are disarmed and deleted by an
.Xr exec 3 .
.Sh RETURN VALUES
If successful, the
.Fn timer_create
function returns 0, and fills in the
.Ar timerid
argument with the id of the new timer that was created.
Otherwise, it returns \-1, and sets
.Dv errno
to indicate the error.
.Sh ERRORS
The
.Fn timer_create
function will fail if:
.Bl -tag -width Er
.It Bq Er EAGAIN
The system is out of resources to satisfy this request, or the process has
created all the timers it is allowed.
.It Bq Er EINVAL
The argument
.Ar clockid
is not a valid clock id.
.El
.Sh SEE ALSO
.Xr clock_getres 2 ,
.Xr clock_gettime 2 ,
.Xr clock_settime 2 ,
.Xr timer_delete 2 ,
.Xr timer_getoverrun 2 ,
.Xr timer_gettime 2 ,
.Xr timer_settime 2 ,
.Xr sigevent 3
.Sh STANDARDS
.St -p1003.1b-93 ,
.St -p1003.1i-95