xref: /netbsd-src/lib/libc/sys/timer_create.2 (revision da9817918ec7e88db2912a2882967c7570a83f47)
1.\"	$NetBSD: timer_create.2,v 1.9 2009/03/26 16:55:37 drochner Exp $
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7.\" by Christos Zoulas.
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30.Dd September 13, 2003
31.Dt TIMER_CREATE 2
32.Os
33.Sh NAME
34.Nm timer_create
35.Nd create a per-process timer
36.Sh LIBRARY
37.Lb libc
38.Sh SYNOPSIS
39.In time.h
40.In signal.h
41.Ft int
42.Fn timer_create "clockid_t clockid" "struct sigevent * restrict evp" "timer_t * restrict timerid"
43.Sh DESCRIPTION
44The
45.Fn timer_create
46function creates a per-process timer using the clock specified in the
47.Ar clockid
48argument.
49If it succeeds, the
50.Fn timer_create
51function fills in the
52.Ar timerid
53argument with an id associated with the timer created that can be used by
54other timer related calls.
55The
56.Ar clockid
57must be a valid clock id as defined in
58.Aq Pa time.h .
59The timer is created in a disarmed state.
60.Pp
61An optional
62.Pq non- Ns Dv NULL
63sigevent argument can be specified by the
64.Ar evp
65argument.
66If the
67.Ar evp
68argument is
69.Dv NULL ,
70then it defaults to
71.Fa sigev_notify
72set to
73.Dv SIGEV_SIGNAL
74and
75.Fa sigev_value
76set to
77.Ar timerid .
78See
79.Xr siginfo 2
80for accessing those values from a signal handler.
81.Sh NOTES
82Timers are not inherited after a
83.Xr fork 2
84and are disarmed and deleted by an
85.Xr exec 3 .
86.Sh RETURN VALUES
87If successful, the
88.Fn timer_create
89function returns 0, and fills in the
90.Ar timerid
91argument with the id of the new timer that was created.
92Otherwise, it returns \-1, and sets
93.Dv errno
94to indicate the error.
95.Sh ERRORS
96The
97.Fn timer_create
98function will fail if:
99.Bl -tag -width Er
100.It Bq Er EAGAIN
101The system is out of resources to satisfy this request, or the process has
102created all the timers it is allowed.
103.It Bq Er EINVAL
104The argument
105.Ar clockid
106is not a valid clock id.
107.El
108.Sh SEE ALSO
109.Xr clock_getres 2 ,
110.Xr clock_gettime 2 ,
111.Xr clock_settime 2 ,
112.Xr timer_delete 2 ,
113.Xr timer_getoverrun 2 ,
114.Xr timer_gettime 2 ,
115.Xr timer_settime 2
116.Sh STANDARDS
117.St -p1003.1b-93 ,
118.St -p1003.1i-95
119