Fix a number of typos in manual pages and user-visible messages.
[dragonfly.git] / share / man / man9 / vn_lock.9
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1.\" Copyright (c) 1996 Doug Rabson
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28.Dd November 17, 2014
4ced8123 29.Dt VN_LOCK 9
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30.Os
31.Sh NAME
32.Nm vn_lock ,
33.Nm vn_unlock ,
34.Nm vn_islocked
35.Nd serialize access to a vnode
36.Sh SYNOPSIS
37.In sys/vnode.h
38.Ft int
39.Fn vn_lock "struct vnode *vp" "int flags"
40.Ft void
41.Fn vn_unlock "struct vnode *vp"
42.Ft int
43.Fn vn_islocked "struct vnode *vp"
44.Sh DESCRIPTION
45These calls are used to serialize access to the filesystem, such as
46to prevent two writes to the same file from happening at the
47same time.
48.Pp
49The arguments are:
50.Bl -tag -width flags
51.It Fa vp
52the vnode being locked or unlocked
53.It Fa flags
54One of the lock request types:
55.Bl -column ".Dv LK_FAILRECLAIM" -offset indent
56.It Dv LK_RETRY Ta "Automatically retry on timeout"
57.It Dv LK_FAILRECLAIM Ta "Fail if the vnode is being reclaimed"
58.El
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59.El
60.Pp
61The
62.Fn vn_lock
63function will require either
64.Dv LK_EXCLUSIVE
65or
66.Dv LK_SHARED
67to be
68.Em or Ns 'ed
69with the request flags described above in order to specify the type
70of lock to be used.
71.Pp
72The
73.Fn vn_unlock
74function uses
75.Dv LK_RELEASE
76internally to release a previously held lock.
77.Pp
78Please note all these functions rely on
79.Xr lockmgr 9
80to perform their operations.
81.Sh RETURN VALUES
82The
83.Fn vn_lock
1ef3b4ca 84function returns zero on success and non-zero on failure.
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85.Pp
86The
87.Fn vn_islocked
88function has identical return values as
89.Xr lockstatus 9 .
90.Sh SEE ALSO
08aa45b7 91.Xr lockmgr 9 ,
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92.Xr vnode 9
93.Sh AUTHORS
94This man page was written by
95.An Doug Rabson .