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VREF(9) FreeBSD Kernel Developer's Manual VREF(9)
NAME
vref, vrefl - increment the use count for a vnode
SYNOPSIS
#include <sys/param.h>
#include <sys/vnode.h>
void
vref(struct vnode *vp);
void
vrefl(struct vnode *vp);
DESCRIPTION
Increment the v_usecount field of a vnode.
vp the vnode to increment
Each vnode maintains a reference count of how many parts of the system
are using the vnode. This allows the system to detect when a vnode is no
longer being used and can be safely recycled for a different file.
Any code in the system which is using a vnode (e.g. during the operation
of some algorithm or to store in a data structure) should call vref() or
vrefl().
vref() locks the vnode interlock while vrefl() expects the interlock to
already be held.
SEE ALSO
vget(9), vnode(9), vput(9), vrefcnt(9), vrele(9)
AUTHORS
This manual page was written by Doug Rabson.
FreeBSD 14.0-RELEASE-p11 January 18, 2016 FreeBSD 14.0-RELEASE-p11