.\" -*- nroff -*-
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.\" Copyright (c) 1996 Doug Rabson
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.Dd July 24, 1996
.Os
.Dt VOP_SEEK
.Sh NAME
.Nm VOP_SEEK
.Nd seek to a given location in a file
.Sh SYNOPSIS
.Fd #include <sys/vnode.h>
.Ft int
.Fn VOP_SEEK "struct vnode *vp" "off_t oldoff" "off_t newoff" "struct ucred *cred"
.Sh DESCRIPTION
This seeks to a given location in a file, possibly extending the file.
Most filesystems do not implement this entry point and automatically
extend the file when it is written to.
In fact, the only place in the entire kernel where this is called is
from the union filesystem and then only to implement its own VOP_SEEK
entry point.
.Pp
Its arguments are:
.Bl -tag -width 8X
.It Ar vp
the vnode of the file
.It Ar oldoff
an offset
.It Ar newoff
another offset
.It Ar cred
the caller's credentials
.El
.Sh PSEUDOCODE
.Bd -literal
int
vop_seek(struct vnode *vp, off_t oldoff, off_t newoff, struct ucred *cred)
{
    return 0;
}
.Ed
.Sh SEE ALSO
.Xr vnode 9
.Sh AUTHORS
This man page was written by Doug Rabson.