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_NOTIFY 9 28.Os 29.Sh NAME 30.Nm devctl_notify 31.Nd Send a message, via devctl, to userland 32.Sh SYNOPSIS 33.In sys/devctl.h 34.Ft void 35.Fn devctl_notify "const char *system" "const char *subsystem" "const char *type" "const char *data" 36.Sh DESCRIPTION 37Send a notification to user land via 38.Xr devctl 4 . 39See 40.Xr devctl 4 41for the format of these messages. 42.Pp 43The 44.Nm 45function creates a string using the following template: 46.Bd -literal 47snprintf(buffer, sizeof(buffer), "!system=%s subsystem=%s type=%s", 48 system, subsystem, type); 49.Ed 50.Pp 51The 52.Va system , 53.Va subsystem , 54and 55.Va type 56pointers cannot be NULL. 57.Pp 58The 59.Va data 60argument may be NULL (for no additions) or a message formatted 61properly for 62.Xr devctl 4 . 63A space will be added to the above template and this argument copied 64verbatim to form the message passed to userland. 65Senders should balance between only passing data that userland can not 66discover itself and sending all the data userland will want to use to 67decide what to do with the message. 68.Pp 69The current total message length limit is just under 1kb. 70Senders should try to remain well below this limit. 71.Sh SEE ALSO 72.Xr devctl 4 , 73.Xr devd 8 74.Sh AUTHORS 75This manual page was written by 76.An M. Warner Losh 77