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sbread(3) [freebsd man page]

SBREAD(3)						   BSD Library Functions Manual 						 SBREAD(3)

NAME
sbread, sbwrite -- read 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 oper- ate 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). 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

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UFS_DISK_CLOSE(3)					   BSD Library Functions Manual 					 UFS_DISK_CLOSE(3)

NAME
ufs_disk_close, ufs_disk_fillout, ufs_disk_fillout_blank, ufs_disk_write -- open and close userland UFS disks 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 ufs_disk_close(struct uufsd *disk); int ufs_disk_fillout(struct uufsd *disk, const char *name); int ufs_disk_fillout_blank(struct uufsd *disk, const char *name); int ufs_disk_write(struct uufsd *disk); DESCRIPTION
The ufs_disk_close() function closes a disk and frees internal memory related to it. It does not free the disk structure. The ufs_disk_fillout() and ufs_disk_fillout_blank() functions open a disk specified by name and populate the structure pointed to by disk. The disk is opened read-only. The specified name may be either a mountpoint, a device name or a filesystem image. The ufs_disk_fillout() function assumes there is a valid superblock and will fail if not, whereas the ufs_disk_fillout_blank() function makes no assumptions of that sort. The ufs_disk_write() function attempts to re-open a disk as writable if it is not currently. ERRORS
The function ufs_disk_close() has no failure points. The function ufs_disk_fillout() may fail for any of the reasons ufs_disk_fillout_blank() might, as well as for any reason sbread(3) might. The ufs_disk_fillout_blank() may fail and set errno for any of the errors specified for the library functions open(2), strdup(3). Addition- ally, it may follow the libufs(3) error methodologies in situations where no device could be found to open. The function ufs_disk_write() may fail and set errno for any of the errors specified for the library functions open(2) and stat(2). Namely, it will fail if the disk in question may not be written to. SEE ALSO
open(2), getfsfile(3), libufs(3), sbread(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

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