xref: /freebsd/share/man/man9/vget.9 (revision 2e3f49888ec8851bafb22011533217487764fdb0)
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29.Dd July 24, 1996
30.Dt VGET 9
31.Os
32.Sh NAME
33.Nm vget
34.Nd get a vnode from the free list
35.Sh SYNOPSIS
36.In sys/param.h
37.In sys/vnode.h
38.Ft int
39.Fn vget "struct vnode *vp" "int lockflag" "struct thread *td"
40.Sh DESCRIPTION
41Get a vnode from the free list and increment its reference count.
42.Bl -tag -width lockflag
43.It Fa vp
44The vnode to remove from the free list.
45.It Fa lockflag
46If non-zero, the vnode will also be locked.
47.El
48.Pp
49When not in use, vnodes are kept on a free list.
50The vnodes still
51reference valid files but may be reused to refer to a new file at any
52time.
53Often, these vnodes are also held in caches in the system, such
54as the name cache.
55.Pp
56When a vnode which is on the free list is used again, for instance if
57the vnode was found in the name cache as a result of a call to
58.Xr VOP_LOOKUP 9
59then the new user must call
60.Fn vget
61to increment the reference count and remove it from the free list.
62.Sh SEE ALSO
63.Xr vnode 9 ,
64.Xr vput 9 ,
65.Xr vref 9 ,
66.Xr vrele 9
67.Sh AUTHORS
68This manual page was written by
69.An Doug Rabson .
70