1.\" -*- nroff -*- 2.\" 3.\" Copyright (c) 1998 Doug Rabson 4.\" 5.\" All rights reserved. 6.\" 7.\" This program is free software. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR 19.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT, 22.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28.\" 29.\" $FreeBSD$ 30.\" 31.Dd January 21, 2015 32.Dt DEVICE_GET_SOFTC 9 33.Os 34.Sh NAME 35.Nm device_get_softc 36.Nd access driver private instance variables 37.Sh SYNOPSIS 38.In sys/param.h 39.In sys/bus.h 40.Ft void * 41.Fn device_get_softc "device_t dev" 42.Sh DESCRIPTION 43Return the driver-specific software context of 44.Fa dev . 45The softc is automatically allocated and zeroed when the device is 46attached. 47The softc is also initialized and present when a device is probed, 48but is subject to caveats as described in 49.Xr DEVICE_PROBE 9 . 50The size of the allocation is determined by the device's 51.Vt driver_t 52information used to define the driver. 53The softc typically encapsulates the state of this instance of the 54device. 55.Pp 56Driver writers are discouraged from using their own softc management 57mechanisms. 58Driver writers should not copy such mechanisms found in drivers in the 59tree that predate this function. 60.Sh RETURN VALUES 61The pointer to the driver-specific instance variable is returned. 62.Sh SEE ALSO 63.Xr device 9 , 64.Xr DEVICE_PROBE 9 , 65.Xr device_set_softc 9 , 66.Xr driver 9 67.Sh AUTHORS 68This manual page was written by 69.An Doug Rabson . 70