xref: /netbsd-src/lib/libc/sys/timer_create.2 (revision 23c8222edbfb0f0932d88a8351d3a0cf817dfb9e)
1.\"	$NetBSD: timer_create.2,v 1.7 2004/03/14 10:36:09 snj Exp $
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3.\" Copyright (c) 2003 The NetBSD Foundation, Inc.
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6.\" This code is derived from software contributed to The NetBSD Foundation
7.\" by Christos Zoulas.
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37.Dd September 13, 2003
38.Dt TIMER_CREATE 2
39.Os
40.Sh NAME
41.Nm timer_create
42.Nd create a per-process timer
43.Sh LIBRARY
44.Lb libc
45.Sh SYNOPSIS
46.In time.h
47.In signal.h
48.Ft int
49.Fn timer_create "clockid_t clockid" "struct sigevent * restrict evp" "timer_t * restrict timerid"
50.Sh DESCRIPTION
51The
52.Fn timer_create
53function creates a per-process timer using the clock specified in the
54.Ar clockid
55argument.
56If it succeeds, the
57.Fn timer_create
58function fills in the
59.Ar timerid
60argument with an id associated with the timer created that can be used by
61other timer related calls.
62The
63.Ar clockid
64must be a valid clock id as defined in
65.Aq Pa time.h .
66The timer is created in a disarmed state.
67.Pp
68An optional
69.Pq non- Ns Dv NULL
70sigevent argument can be specified by the
71.Ar evp
72argument.
73If the
74.Ar evp
75argument is
76.Dv NULL ,
77then it defaults to
78.Fa sigev_notify
79set to
80.Dv SIGEV_SIGVAL
81and
82.Fa sigev_value
83set to
84.Ar timerid .
85See
86.Xr siginfo 2
87for accessing those values from a signal handler.
88.Sh NOTES
89Timers are not inherited after a
90.Xr fork 2
91and are disarmed and deleted by an
92.Xr exec 3 .
93.Sh RETURN VALUES
94If successful, the
95.Fn timer_create
96function returns 0, and fills in the
97.Ar timerid
98argument with the id of the new timer that was created.
99Otherwise, it returns \-1, and sets
100.Dv errno
101to indicate the error.
102.Sh ERRORS
103The
104.Fn timer_create
105function will fail if:
106.Bl -tag -width Er
107.It Bq Er EAGAIN
108The system is out of resources to satisfy this request, or the process has
109created all the timers it is allowed.
110.It Bq Er EINVAL
111The argument
112.Ar clockid
113is not a valid clock id.
114.El
115.Sh SEE ALSO
116.Xr clock_getres 2 ,
117.Xr clock_gettime 2 ,
118.Xr clock_settime 2 ,
119.Xr timer_delete 2 ,
120.Xr timer_getoverrun 2 ,
121.Xr timer_gettime 2 ,
122.Xr timer_settime 2
123.Sh STANDARDS
124.St -p1003.1b-93 ,
125.St -p1003.1i-95
126