device_get_softc (9)

Leading comments

Copyright (c) 1998 Doug Rabson

All rights reserved.

This program is free software.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.
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   notice, this list of conditions and the following disclaimer in...

(The comments found at the beginning of the groff file "man9/device_get_softc.9freebsd".)

NAME

device_get_softc - access driver private instance variables

SYNOPSIS

In sys/param.h In sys/bus.h Ft void * Fn device_get_softc device_t dev

DESCRIPTION

Return the driver-specific state of Fa dev . The softc is automatically allocated and zeroed when the device is attached. The softc is also initialized and present when a device is probed, but is subject to caveats as described in DEVICE_PROBE9. The size of the allocation is determined by the device's Vt driver_t information used to define the driver. The softc typically encapsulates the state of this instance of the device.

Driver writers are discouraged from using their own softc management mechanisms. Driver writers should not copy such mechanisms found in drivers in the tree that predate this function.

RETURN VALUES

The pointer to the driver-specific instance variable is returned.

SEE ALSO

device(9), DEVICE_PROBE9, device_set_softc9, driver(9)

AUTHORS

This manual page was written by An Doug Rabson .