.\" Copyright (c) 1996 Doug Rabson
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.\" $FreeBSD: src/share/man/man9/VOP_ADVLOCK.9,v 1.6.2.3 2001/12/17 11:30:18 ru Exp $
.\"
.Dd June 30, 1999
.Dt VOP_ADVLOCK 9
.Os
.Sh NAME
.Nm VOP_ADVLOCK
.Nd advisory record locking
.Sh SYNOPSIS
.In sys/param.h
.In sys/vnode.h
.In sys/fcntl.h
.In sys/lockf.h
.Ft int
.Fn VOP_ADVLOCK "struct vnode *vp" "caddr_t id" "int op" "struct flock *fl" "int flags"
.Sh DESCRIPTION
The arguments are:
.Bl -tag -width flags
.It Fa vp
the vnode being manipulated
.It Fa id
the id token which is changing the lock
.It Fa op
the operation to perform (see
.Xr fcntl 2 )
.It Fa fl
description of the lock
.It Fa flags
One of more of the following:
.Bl -column ".Dv F_UNLCK" -offset indent
.It Dv F_RDLCK Ta "shared or read lock"
.It Dv F_UNLCK Ta "unlock"
.It Dv F_WRLCK Ta "exclusive or write lock"
.It Dv F_WAIT Ta "Wait until lock is granted"
.It Dv F_POSIX Ta "Use POSIX semantics for lock"
.El
.El
.Pp
This entry point manipulates advisory record locks on the file.  Most
filesystems delegate the work for this call to
.Fn lf_advlock .
.Sh RETURN VALUES
Zero is returned on success, otherwise an error is returned.
.Sh SEE ALSO
.Xr fcntl 2 ,
.Xr flock 2 ,
.Xr vnode 9
.Sh AUTHORS
This man page was written by
.An Doug Rabson .