xref: /freebsd/share/man/man9/vget.9 (revision 2be1a816b9ff69588e55be0a84cbe2a31efc0f2f)
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29.\" $FreeBSD$
30.\"
31.Dd July 24, 1996
32.Os
33.Dt VGET 9
34.Sh NAME
35.Nm vget
36.Nd get a vnode from the free list
37.Sh SYNOPSIS
38.In sys/param.h
39.In sys/vnode.h
40.Ft int
41.Fn vget "struct vnode *vp" "int lockflag" "struct thread *td"
42.Sh DESCRIPTION
43Get a vnode from the free list and increment its reference count.
44.Bl -tag -width lockflag
45.It Fa vp
46The vnode to remove from the free list.
47.It Fa lockflag
48If non-zero, the vnode will also be locked.
49.El
50.Pp
51When not in use, vnodes are kept on a free list.
52The vnodes still
53reference valid files but may be reused to refer to a new file at any
54time.
55Often, these vnodes are also held in caches in the system, such
56as the name cache.
57.Pp
58When a vnode which is on the free list is used again, for instance if
59the vnode was found in the name cache as a result of a call to
60.Xr VOP_LOOKUP 9
61then the new user must call
62.Fn vget
63to increment the reference count and remove it from the free list.
64.Sh SEE ALSO
65.Xr vnode 9 ,
66.Xr vput 9 ,
67.Xr vref 9 ,
68.Xr vrele 9
69.Sh AUTHORS
70This manual page was written by
71.An Doug Rabson .
72