EN JA
SBREAD(3)
SBREAD(3) FreeBSD Library Functions Manual SBREAD(3)

NAME

sbread, sbwriteread and write superblocks of a UFS file system

LIBRARY

UFS File System Access Library (libufs, -lufs)

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() functions 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() and sbwrite() functions return 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).

HISTORY

These functions first appeared as part of libufs(3) in FreeBSD 5.0.

AUTHORS

Juli Mallett <jmallett@FreeBSD.org>
June 4, 2003 FreeBSD