freebsd-skq/share/man/man9/device_find_child.9

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.\" Copyright (c) 1998 Doug Rabson
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1999-08-28 00:22:10 +00:00
.\" $FreeBSD$
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.Dd February 8, 2005
.Dt DEVICE_FIND_CHILD 9
.Os
.Sh NAME
.Nm device_find_child
.Nd search for a child of a device
.Sh SYNOPSIS
.In sys/param.h
.In sys/bus.h
.Ft device_t
.Fn device_find_child "device_t dev" "const char *classname" "int unit"
.Sh DESCRIPTION
This function looks for a specific child of
.Dv dev
with the given
.Fa classname
and
.Fa unit .
If
.Fa unit
is \-1, it returns the first child of
.Fa dev
with a matching
.Fa classname
(that is, the one with the lowest unit).
.Sh RETURN VALUES
If it exists, the child device is returned, otherwise NULL.
.Sh SEE ALSO
.Xr device_add_child 9
.Sh AUTHORS
This manual page was written by
.An Doug Rabson .