xref: /freebsd/share/man/man9/devctl_process_running.9 (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
1.\"
2.\" Copyright (c) 2020 M Warner Losh
3.\"
4.\" Redistribution and use in source and binary forms, with or without
5.\" modification, are permitted provided that the following conditions
6.\" are met:
7.\" 1. Redistributions of source code must retain the above copyright
8.\"    notice, this list of conditions and the following disclaimer.
9.\" 2. Redistributions in binary form must reproduce the above copyright
10.\"    notice, this list of conditions and the following disclaimer in the
11.\"    documentation and/or other materials provided with the distribution.
12.\"
13.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR
14.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
15.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
16.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT,
17.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
18.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
19.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
20.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
21.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
22.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23.\"
24.\" $FreeBSD$
25.\"
26.Dd September 22, 2020
27.Dt DEVCTL_PROCESS_RUNNING 9
28.Os
29.Sh NAME
30.Nm devctl_process_running
31.Nd Returns true when devctl has a consumer process running
32.Sh SYNOPSIS
33.In sys/devctl.h
34.Ft bool
35.Fn devctl_process_running "void"
36.Sh DESCRIPTION
37The
38.Nm
39call returns
40.Vt true
41when a process has the devctl device open for
42reading, and
43.Vt false
44otherwise.
45One can assume from this that the default
46.Xr devd 8
47or similar is running when
48.Vt true
49is returned.
50Some subsystems will send a message and allow userland to do something
51before proceeding with a default action if there's a timeout.
52This call allows those subsystems to do the default action right away
53when no process is running.
54.Sh SEE ALSO
55.Xr devd 8
56.Sh AUTHORS
57This manual page was written by
58.An M. Warner Losh
59