freebsd-dev/share/man/man9/vcount.9
Ed Schouten 5dc6c3a38a Remove remnants of dev_t.
These functions take a `struct cdev *' -- not a dev_t. Inside the
kernel, dev_t has the same use as in userspace, namely to store a device
identifier.

MFC after:	2 weeks
2012-01-19 09:51:07 +00:00

74 lines
2.3 KiB
Groff

.\" -*- nroff -*-
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.\" Copyright (c) 2000 Andrew Stevenson
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.\" $FreeBSD$
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.Dd January 19, 2012
.Dt VCOUNT 9
.Os
.Sh NAME
.Nm vcount ,
.Nm count_dev
.Nd "get total number of references to a device"
.Sh SYNOPSIS
.In sys/param.h
.In sys/time.h
.In sys/conf.h
.In sys/vnode.h
.Ft int
.Fn vcount "struct vnode *vp"
.Ft int
.Fn count_dev "struct cdev *dev"
.Sh DESCRIPTION
.Fn vcount
is used to get the number of references to a particular device.
It allows for the fact that multiple vnodes may reference the same device.
.Fn count_dev
does the same thing as
.Fn vcount ,
but takes a
.Vt "struct cdev"
rather than a
.Vt "struct vnode"
pointer as an argument.
.Sh RETURN VALUES
.Fn vcount
and
.Fn count_dev
both return the number of references to the device.
.Sh SEE ALSO
.Xr VFS 9 ,
.Xr vnode 9
.Sh AUTHORS
This manual page was written by
.An Andrew Stevenson .