1.\" 2.\" Copyright (c) 2020 M Warner Losh 3.\" 4.\" This program is free software. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR 16.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT, 19.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25.\" 26.\" $FreeBSD$ 27.\" 28.Dd September 22, 2020 29.Dt DEVCTL_NOTIFY 9 30.Os 31.Sh NAME 32.Nm devctl_notify 33.Nd Send a message, via devctl, to userland 34.Sh SYNOPSIS 35.In sys/devctl.h 36.Ft void 37.Fn devctl_notify "const char *system" "const char *subsystem" "const char *type" "const char *data" 38.Sh DESCRIPTION 39Send a notification to user land via 40.Xr devctl 4 . 41See 42.Xr devctl 4 43for the format of these messages. 44.Pp 45The 46.Nm 47function creates a string using the following template: 48.Bd -literal 49snprintf(buffer, sizeof(buffer), "!system=%s subsystem=%s type=%s", 50 system, subsystem, type); 51.Ed 52.Pp 53The 54.Va system , 55.Va subsystem , 56and 57.Va type 58pointers cannot be NULL. 59.Pp 60The 61.Va data 62argument may be NULL (for no additions) or a message formatted 63properly for 64.Xr devctl 4 . 65A space will be added to the above template and this argument copied 66verbatim to form the message passed to userland. 67Senders should balance between only passing data that userland can not 68discover itself and sending all the data userland will want to use to 69decide what to do with the message. 70.Pp 71The current total message length limit is just under 1kb. 72Senders should try to remain well below this limit. 73.Sh SEE ALSO 74.Xr devctl 4 , 75.Xr devd 8 76.Sh AUTHORS 77This manual page was written by 78.An M. Warner Losh 79