FreeBSD-5.3/share/man/man9/device_get_softc.9

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.Dd June 16, 1998
.Dt DEVICE_GET_SOFTC 9
.Os
.Sh NAME
.Nm device_get_softc
.Nd access driver private instance variables
.Sh SYNOPSIS
.In sys/param.h
.In sys/bus.h
.Ft void *
.Fn device_get_softc "device_t dev"
.Sh DESCRIPTION
Return the driver-specific state of
.Fa dev .
The softc is automatically allocated the first time it is requested.
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.
.Pp
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 predates this function.
.Sh RETURN VALUES
The pointer to the driver-specific instance variable is returned.
.Sh SEE ALSO
.Xr device 9 ,
.Xr device_set_softc 9 ,
.Xr driver 9
.Sh AUTHORS
This manual page was written by
.An Doug Rabson .