xref: /dflybsd-src/share/man/man9/vcount.9 (revision 86d7f5d305c6adaa56ff4582ece9859d73106103)
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32*86d7f5d3SJohn Marino.Dd December 14, 2009
33*86d7f5d3SJohn Marino.Dt VCOUNT 9
34*86d7f5d3SJohn Marino.Os
35*86d7f5d3SJohn Marino.Sh NAME
36*86d7f5d3SJohn Marino.Nm vcount ,
37*86d7f5d3SJohn Marino.Nm count_dev
38*86d7f5d3SJohn Marino.Nd "get total number of references to a device"
39*86d7f5d3SJohn Marino.Sh SYNOPSIS
40*86d7f5d3SJohn Marino.In sys/conf.h
41*86d7f5d3SJohn Marino.In sys/vnode.h
42*86d7f5d3SJohn Marino.Ft int
43*86d7f5d3SJohn Marino.Fn vcount "struct vnode *vp"
44*86d7f5d3SJohn Marino.Ft int
45*86d7f5d3SJohn Marino.Fn count_dev "cdev_t dev"
46*86d7f5d3SJohn Marino.Sh DESCRIPTION
47*86d7f5d3SJohn Marino.Fn vcount
48*86d7f5d3SJohn Marinois used to get the number of references to a special device.
49*86d7f5d3SJohn MarinoThis makes sense because multiple vnodes may reference the same device.
50*86d7f5d3SJohn Marino.Pp
51*86d7f5d3SJohn Marino.Fn count_dev
52*86d7f5d3SJohn Marinodoes the same thing as
53*86d7f5d3SJohn Marino.Fn vcount ,
54*86d7f5d3SJohn Marinobut takes a
55*86d7f5d3SJohn Marino.Vt cdev_t
56*86d7f5d3SJohn Marinorather than a
57*86d7f5d3SJohn Marino.Vt "struct vnode"
58*86d7f5d3SJohn Marinopointer as an argument.
59*86d7f5d3SJohn MarinoIt may only be called for
60*86d7f5d3SJohn Marino.Dv VBLK
61*86d7f5d3SJohn Marinoand
62*86d7f5d3SJohn Marino.Dv VCHR
63*86d7f5d3SJohn Marinovnodes since
64*86d7f5d3SJohn Marino.Fa v_rdev
65*86d7f5d3SJohn Marinois an overloaded field.
66*86d7f5d3SJohn Marino.Sh RETURN VALUES
67*86d7f5d3SJohn Marino.Fn vcount
68*86d7f5d3SJohn Marinoand
69*86d7f5d3SJohn Marino.Fn count_dev
70*86d7f5d3SJohn Marinoboth return the number of references to the device.
71*86d7f5d3SJohn Marino.Sh SEE ALSO
72*86d7f5d3SJohn Marino.Xr vnode 9
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