1 .\" Copyright (c) 2005 David Xu <davidxu@FreeBSD.org>
2 .\" All rights reserved.
4 .\" Redistribution and use in source and binary forms, with or without
5 .\" modification, are permitted provided that the following conditions
7 .\" 1. Redistributions of source code must retain the above copyright
8 .\" notice(s), this list of conditions and the following disclaimer as
9 .\" the first lines of this file unmodified other than the possible
10 .\" addition of one or more copyright notices.
11 .\" 2. Redistributions in binary form must reproduce the above copyright
12 .\" notice(s), this list of conditions and the following disclaimer in
13 .\" the documentation and/or other materials provided with the
16 .\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
17 .\" EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19 .\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
20 .\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
23 .\" BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
24 .\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
25 .\" OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
26 .\" EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35 .Nd "create a per-process timer (REALTIME)"
43 .Fa "clockid_t clockid" "struct sigevent *restrict evp"
44 .Fa "timer_t *restrict timerid"
49 system call creates a per-process timer using the specified clock,
54 system call returns, in the location referenced by
58 used to identify the timer in timer requests.
59 This timer ID is unique within the calling process until the timer is deleted.
64 The timer whose ID is returned is in a disarmed state upon return from
75 allocated by the application, defines the asynchronous notification to occur
76 when the timer expires.
84 the signal specified in
86 will be sent to the calling process
88 or to the thread whose LWP ID is
89 .Fa evp->sigev_notify_thread_id
90 .Pq Dv SIGEV_THREAD_ID .
91 The information for the queued signal will include:
92 .Bl -column ".Va si_value"
93 .It Sy Member Ta Sy Value
94 .It Va si_code Ta Dv SI_TIMER
98 .It Va si_timerid Ta timer ID
99 .It Va si_overrun Ta timer overrun count
102 .Brq Dv DELAYTIMER_MAX ,
103 an error code defined in
111 the effect is as if the
113 argument pointed to a
117 member having the value
121 having a default signal number
126 the value of the timer ID.
128 This implementation supports a
133 .Dv CLOCK_MONOTONIC .
136 .Fa evp->sigev_notify
140 .Fa sev->sigev_notify_attributes
143 if the attribute pointed to by
144 .Fa sev->sigev_notify_attributes
146 a thread stack address specified by a call to
147 .Fn pthread_attr_setstack
149 .Fn pthread_attr_setstackaddr ,
150 the results are unspecified if the signal is generated more than once.
152 If the call succeeds,
154 returns zero and updates the location referenced by
158 which can be passed to the per-process timer calls.
160 occurs, the system call returns a value of \-1
161 and the global variable
163 is set to indicate the
167 is undefined if an error occurs.
175 The calling process has already created all of the timers it is allowed by
178 The specified clock ID is not supported.
180 The specified asynchronous notification method is not supported.
182 Any arguments point outside the allocated address space or there is a
183 memory protection fault.
188 .Xr timer_getoverrun 2 ,
194 system call conforms to
199 per-process timer first appeared in