xref: /freebsd/share/man/man9/devctl_process_running.9 (revision c66ec88fed842fbaad62c30d510644ceb7bd2d71)
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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