sbread(3)

NAME

sbread, sbwrite - read and write superblocks of a UFS file

system

LIBRARY

library ``libufs''

SYNOPSIS

#include <sys/param.h>
#include <sys/mount.h>
#include <ufs/ufs/ufsmount.h>
#include <ufs/ufs/dinode.h>
#include <ufs/ffs/fs.h>
#include <libufs.h>
int
sbread(struct uufsd *disk);
int
sbwrite(struct uufsd *disk, int all);

DESCRIPTION

The sbread() and sbwrite() functions provide superblock

reads and writes
for libufs(3) consumers. The sbread() and sbwrite() func

tions operate on
the superblock field, d_sb, associated with a given userland

UFS disk
structure. Additionally, the sbwrite() function will write

to all
superblock locations if the all value is non-zero.

RETURN VALUES

The sbread() function returns the value 0 if successful;

otherwise the
value -1 is returned and the global variable errno is set to

indicate the
error.

ERRORS

The function sbread() may fail and set errno for any of the

errors specified for the library function bread(3). Additionally, it

may follow the
libufs(3) error methodologies in situations where no usable

superblock
could be found.

The function sbwrite() may fail and set errno for any of the

errors specified for the library function bwrite(3).

SEE ALSO

bread(3), bwrite(3), libufs(3)

HISTORY

These functions first appeared as part of libufs(3) in

FreeBSD 5.0.

AUTHORS

Juli Mallett <jmallett@FreeBSD.org>

BSD June 4, 2003

BSD