xref: /freebsd/share/man/man9/VOP_STRATEGY.9 (revision 1d386b48)
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29.\" $FreeBSD$
30.\"
31.Dd June 30, 2022
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/buf.h
40.In sys/vnode.h
41.Ft int
42.Fn VOP_STRATEGY "struct vnode *vp" "struct buf *bp"
43.Sh DESCRIPTION
44The arguments are:
45.Bl -tag -width 2n
46.It Fa vp
47The vnode that the buffer is for.
48.It Fa bp
49The buffer to be read or written.
50.El
51.Pp
52This call either reads or writes data from a file, depending on the value of
53.Fa bp->b_iocmd .
54.Pp
55The call may block.
56.Sh RETURN VALUES
57Always zero.
58Errors should be signalled by setting the
59.Dv BIO_ERROR
60bit in
61.Fa bp->b_ioflags
62and setting
63.Fa bp->b_error
64to the appropriate
65.Va errno
66value.
67.Sh SEE ALSO
68.Xr errno 2 ,
69.Xr buf 9 ,
70.Xr vnode 9
71.Sh AUTHORS
72This manual page was written by
73.An Doug Rabson .
74