xref: /freebsd/share/man/man9/VOP_STRATEGY.9 (revision 6b7b2d80ed4d728d3ffd12c422e57798c1b63a84)
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29.\" $FreeBSD$
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31.Dd February 2, 2014
32.Dt VOP_STRATEGY 9
33.Os
34.Sh NAME
35.Nm VOP_STRATEGY
36.Nd read or write a file system buffer
37.Sh SYNOPSIS
38.In sys/param.h
39.In sys/vnode.h
40.Ft int
41.Fn VOP_STRATEGY "struct vnode *vp" "struct buf *bp"
42.Sh DESCRIPTION
43The arguments are:
44.Bl -tag -width 2n
45.It Fa vp
46The vnode that the buffer is for.
47.It Fa bp
48The buffer to be read or written.
49.El
50.Pp
51This call either reads or writes data from a file, depending on the value of
52.Fa bp->b_io.bio_cmd .
53.Pp
54The call may block.
55.Sh RETURN VALUES
56Always zero.
57Errors should be signalled by setting BIO_ERROR on b_ioflags field in struct buf,
58and setting b_error to the appropriate errno value.
59.Sh SEE ALSO
60.Xr buf 9 ,
61.Xr vnode 9
62.Sh AUTHORS
63This manual page was written by
64.An Doug Rabson .
65