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icheck(8) [bsd man page]

ICHECK(8)						      System Manager's Manual							 ICHECK(8)

icheck - file system storage consistency check SYNOPSIS
icheck [ -s ] [ -b numbers ] [ filesystem ] DESCRIPTION
Icheck examines a file system, builds a bit map of used blocks, and compares this bit map against the free list maintained on the file sys- tem. If the file system is not specified, a set of default file systems is checked. The normal output of icheck includes a report of The total number of files and the numbers of regular, directory, block special and character special files, quota nodes, and sym- bolic links. The total number of blocks in use and the numbers of single-, double-, and triple-indirect blocks and directory blocks. The number of free blocks. The number of blocks missing; i.e. not in any file nor in the free list. The -s option causes icheck to ignore the actual free list and reconstruct a new one by rewriting the super-block of the file system. The file system should be dismounted while this is done; if this is not possible (for example if the root file system has to be salvaged) care should be taken that the system is quiescent and that it is rebooted immediately afterwards so that the old, bad in-core copy of the super- block will not continue to be used. Notice also that the words in the super-block which indicate the size of the free list and of the i- list are believed. If the super-block has been curdled these words will have to be patched. The -s option causes the normal output reports to be suppressed. Following the -b option is a list of block numbers; whenever any of the named blocks turns up in a file, a diagnostic is produced. Icheck is faster if the raw version of the special file is used, since it reads the i-list many blocks at a time. SEE ALSO
filsys(5), clri(8), dcheck(8), fsck(8), ncheck(8) DIAGNOSTICS
For duplicate blocks and bad blocks (which lie outside the file system) icheck announces the difficulty, the i-number, and the kind of block involved. If a read error is encountered, the block number of the bad block is printed and icheck considers it to contain 0. `Bad freeblock' means that a block number outside the available space was encountered in the free list. `n dups in free' means that n blocks were found in the free list which duplicate blocks either in some file or in the earlier part of the free list. BUGS
Since icheck is inherently two-pass in nature, extraneous diagnostics may be produced if applied to active file systems. Since default file systems vary with installations, icheck should use fstab(5). It believes even preposterous super-blocks and consequently can get core images. 3rd Berkeley Distribution ICHECK(8)

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df_hfs(1M)																df_hfs(1M)

df_hfs: df - report number of free CDFS, HFS, or NFS file system disk blocks SYNOPSIS
FStype] specific_options] [special|directory]... DESCRIPTION
The command displays the number of free 512-byte blocks and free inodes available for file systems by examining the counts kept in the superblock or superblocks. If a special or a directory is not specified, the free space on all mounted file systems is displayed. If the arguments to are path names, reports on the file systems containing the named files. If the argument to is a special of an unmounted file system, the free space in the unmounted file system is displayed. Options recognizes the following options: Report only the number of kilobytes (KB) free. Report the total number of blocks allocated for swapping to the file system as well as the number of blocks free for swapping to the file system. This option is supported on HFS file systems only. Report the number of files free. Report only the actual count of the blocks in the free list (free inodes are not reported). When this option is specified, reports on raw devices. Report only on the FStype file system type (see fstyp(1M)). For the purposes of this manual entry, FStype can be one of and for the CDFS, HFS, and NFS file systems, respectively. Report the entire structure described in statvfs(2). Report the total number of inodes, the number of free inodes, number of used inodes, and the percentage of inodes in use. Report the allocation in kilobytes (KB). Report on local file systems only. Report the file system name. If used with no other options, display a list of mounted file system types. Specify options specific to the HFS file system type. specific_options is a comma-separated list of suboptions. The available suboption is: Report the number of used and free inodes. Report the total allocated block figures and the number of free blocks. Report the percentage of blocks used, the number of blocks used, and the number of blocks free. This option cannot be used with other options. Echo the completed command line, but perform no other action. The command line is generated by incorporating the user-specified options and other information derived from This option allows the user to verify the command line. When is used on an HFS file system, the file space reported is the space available to the ordinary user, and does not include the reserved file space specified by Unreported reserved blocks are available only to users who have appropriate privileges. See tunefs(1M) for information about When is used on NFS file systems, the number of inodes is displayed as -1 . This is due to superuser access restrictions over NFS. EXAMPLES
Report the number of free disk blocks for all mounted file systems: Report the number of free disk blocks for all mounted HFS file systems: Report the number of free files for all mounted NFS file systems: Report the total allocated block figures and the number of free blocks, for all mounted file systems: Report the total allocated block figures and the number of free blocks, for the file system mounted as /usr: WARNINGS
does not account for: o Disk space reserved for swap space, o Space used for the HFS boot block (8K bytes, 1 per file system), o HFS superblocks (8K bytes each, 1 per disk cylinder), o HFS cylinder group blocks (1K-8K bytes each, 1 per cylinder group), o Inodes (currently 128 bytes reserved for each inode). Non-HFS file systems may have other items that this command does not account for. The option, from prior releases, has been replaced by the option. FILES
File system devices. Static information about the file systems Mounted file system table SEE ALSO
du(1), df(1M), fsck(1M), fstab(4), fstyp(1M), statvfs(2), mnttab(4). STANDARDS CONFORMANCE

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