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.\" $FreeBSD: releng/12.0/share/man/man9/OF_child.9 332342 2018-04-09 22:23:45Z gonzo $
.\"
.Dd April 9, 2018
.Dt OF_CHILD 9
.Os
.Sh NAME
.Nm OF_child ,
.Nm OF_parent ,
.Nm OF_peer
.Nd navigate device tree
.Sh SYNOPSIS
.In dev/ofw/ofw_bus.h
.In dev/ofw/ofw_bus_subr.h
.Ft phandle_t
.Fn OF_child "phandle_t node"
.Ft phandle_t
.Fn OF_parent "phandle_t node"
.Ft phandle_t
.Fn OF_peer "phandle_t node"
.Sh DESCRIPTION
.Pp
.Fn OF_child
returns the phandle value of the first child of the
.Fa node .
Zero is returned if there are no child nodes.
.Pp
.Fn OF_parent
returns the phandle for the parent of the
.Fa node .
Zero is returned if
.Fa node
is the root node.
.Pp
.Fn OF_peer
returns the phandle value of the next sibling of the
.Fa node .
Zero is returned if there is no sibling node.
.Sh EXAMPLES
.Bd -literal
phandle_t node, child;
 ...
for (child = OF_child(node); child != 0; child = OF_peer(child) {
	...
}
.Ed
.Sh SEE ALSO
.Xr OF_finddevice 9
.Sh AUTHORS
.An -nosplit
This manual page was written by
.An Oleksandr Tymoshenko Aq Mt gonzo@FreeBSD.org .