xref: /freebsd/lib/libufs/sbread.3 (revision a0ee8cc6)
1.\" Author:	Juli Mallett <jmallett@FreeBSD.org>
2.\" Date:	June 04, 2003
3.\" Description:
4.\" 	Manual page for libufs functions:
5.\"		sbread(3)
6.\"		sbwrite(3)
7.\"
8.\" This file is in the public domain.
9.\"
10.\" $FreeBSD$
11.\"
12.Dd June 4, 2003
13.Dt SBREAD 3
14.Os
15.Sh NAME
16.Nm sbread , sbwrite
17.Nd read and write superblocks of a UFS file system
18.Sh LIBRARY
19.Lb libufs
20.Sh SYNOPSIS
21.In sys/param.h
22.In sys/mount.h
23.In ufs/ufs/ufsmount.h
24.In ufs/ufs/dinode.h
25.In ufs/ffs/fs.h
26.In libufs.h
27.Ft int
28.Fn sbread "struct uufsd *disk"
29.Ft int
30.Fn sbwrite "struct uufsd *disk" "int all"
31.Sh DESCRIPTION
32The
33.Fn sbread
34and
35.Fn sbwrite
36functions provide superblock reads and writes for
37.Xr libufs 3
38consumers.
39The
40.Fn sbread
41and
42.Fn sbwrite
43functions operate on the superblock field,
44.Va d_sb ,
45associated with a given userland UFS disk structure.
46Additionally, the
47.Fn sbwrite
48function will write to all superblock locations if the
49.Fa all
50value is non-zero.
51.Sh RETURN VALUES
52.Rv -std sbread sbwrite
53.Sh ERRORS
54The function
55.Fn sbread
56may fail and set
57.Va errno
58for any of the errors specified for the library function
59.Xr bread 3 .
60Additionally, it may follow the
61.Xr libufs 3
62error methodologies in situations where no usable superblock could be
63found.
64.Pp
65The function
66.Fn sbwrite
67may fail and set
68.Va errno
69for any of the errors specified for the library function
70.Xr bwrite 3 .
71.Sh SEE ALSO
72.Xr bread 3 ,
73.Xr bwrite 3 ,
74.Xr libufs 3
75.Sh HISTORY
76These functions first appeared as part of
77.Xr libufs 3
78in
79.Fx 5.0 .
80.Sh AUTHORS
81.An Juli Mallett Aq Mt jmallett@FreeBSD.org
82