1.\" -*- nroff -*- 2.\" 3.\" Copyright (c) 1996 Doug Rabson 4.\" 5.\" All rights reserved. 6.\" 7.\" This program is free software. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR 19.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT, 22.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28.\" 29.Dd June 30, 2022 30.Dt VOP_STRATEGY 9 31.Os 32.Sh NAME 33.Nm VOP_STRATEGY 34.Nd read or write a file system buffer 35.Sh SYNOPSIS 36.In sys/param.h 37.In sys/buf.h 38.In sys/vnode.h 39.Ft int 40.Fn VOP_STRATEGY "struct vnode *vp" "struct buf *bp" 41.Sh DESCRIPTION 42The arguments are: 43.Bl -tag -width 2n 44.It Fa vp 45The vnode that the buffer is for. 46.It Fa bp 47The buffer to be read or written. 48.El 49.Pp 50This call either reads or writes data from a file, depending on the value of 51.Fa bp->b_iocmd . 52.Pp 53The call may block. 54.Sh RETURN VALUES 55Always zero. 56Errors should be signalled by setting the 57.Dv BIO_ERROR 58bit in 59.Fa bp->b_ioflags 60and setting 61.Fa bp->b_error 62to the appropriate 63.Va errno 64value. 65.Sh SEE ALSO 66.Xr errno 2 , 67.Xr buf 9 , 68.Xr vnode 9 69.Sh AUTHORS 70This manual page was written by 71.An Doug Rabson . 72