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.\" $FreeBSD: head/share/man/man9/VOP_STRATEGY.9 261402 2014-02-02 14:13:51Z bdrewery $
.\"
.Dd February 2, 2014
.Dt VOP_STRATEGY 9
.Os
.Sh NAME
.Nm VOP_STRATEGY
.Nd read or write a file system buffer
.Sh SYNOPSIS
.In sys/param.h
.In sys/vnode.h
.Ft int
.Fn VOP_STRATEGY "struct vnode *vp" "struct buf *bp"
.Sh DESCRIPTION
The arguments are:
.Bl -tag -width 2n
.It Fa vp
The vnode that the buffer is for.
.It Fa bp
The buffer to be read or written.
.El
.Pp
This call either reads or writes data from a file, depending on the value of
.Fa bp->b_io.bio_cmd .
.Pp
The call may block.
.Sh RETURN VALUES
Always zero.
Errors should be signalled by setting BIO_ERROR on b_ioflags field in struct buf,
and setting b_error to the appropriate errno value.
.Sh SEE ALSO
.Xr buf 9 ,
.Xr vnode 9
.Sh AUTHORS
This manual page was written by
.An Doug Rabson .