FSDB(8) 						    BSD System Manager's Manual 						   FSDB(8)

NAME

     fsdb -- FFS debugging/editing tool

SYNOPSIS

     fsdb [-dFn] -f fsname

DESCRIPTION

     fsdb opens fsname (usually a raw disk partition) and runs a command loop allowing manipulation of the file system's inode data.  You are
     prompted to enter a command with ``fsdb (inum X)>'' where X is the currently selected i-number.  The initial selected inode is the root of
     the filesystem (i-number 2).  The command processor uses the editline(3) library, so you can use command line editing to reduce typing if
     desired.  When you exit the command loop, the file system superblock is marked dirty and any buffered blocks are written to the file system.

     The -d option enables additional debugging output (which comes primarily from fsck(8)-derived code).

     The -F option indicates that filesystem is a file system image, rather than a raw character device.  It will be accessed 'as-is', and no
     attempts will be made to read a disklabel.

     The -n option disables writing to the device, preventing any changes from being made to the filesystem.

COMMANDS

     Besides the built-in editline(3) commands, fsdb supports these commands:

     help    Print out the list of accepted commands.

     inode i-number
	     Select inode i-number as the new current inode.

     back    Revert to the previously current inode.

     clri    Clear the current inode.

     lookup name
     cd name
	     Find name in the current directory and make its inode the current inode.  Name may be a multi-component name or may begin with slash
	     to indicate that the root inode should be used to start the lookup.  If some component along the pathname is not found, the last
	     valid directory encountered is left as the active inode.
	     This command is valid only if the starting inode is a directory.

     active
     print   Print out the active inode.

     uplink  Increment the active inode's link count.

     downlink
	     Decrement the active inode's link count.

     linkcount number
	     Set the active inode's link count to number.

     ls      List the current inode's directory entries.  This command is valid only if the current inode is a directory.

     blks    List the current inode's blocks numbers.

     findblk disk block number ...
	     Find the inode(s) owning the specified disk block(s) number(s).  Note that these are not absolute disk blocks numbers, but offsets
	     from the start of the partition.

     rm name
     del name
	     Remove the entry name from the current directory inode.  This command is valid only if the current inode is a directory.

     ln ino name
	     Create a link to inode ino under the name name in the current directory inode.  This command is valid only if the current inode is a
	     directory.

     chinum dirslot inum
	     Change the i-number in directory entry dirslot to inum.

     chname dirslot name
	     Change the name in directory entry dirslot to name.  This command cannot expand a directory entry.  You can only rename an entry if
	     the name will fit into the existing directory slot.

     chtype type
	     Change the type of the current inode to type.  type may be one of: file, dir, socket, or fifo.

     chmod mode
	     Change the mode bits of the current inode to mode.  You cannot change the file type with this subcommand; use chtype to do that.

     chflags flags
	     Change the file flags of the current inode to flags.

     chown uid
	     Change the owner of the current inode to uid.

     chgrp gid
	     Change the group of the current inode to gid.

     chgen gen
	     Change the generation number of the current inode to gen.

     mtime time
     ctime time
     atime time
	     Change the modification, change, or access time (respectively) on the current inode to time.  Time should be in the format
	     YYYYMMDDHHMMSS[.nsec] where nsec is an optional nanosecond specification.	If no nanoseconds are specified, the mtimensec, ctimensec,
	     or atimensec field will be set to zero.

     quit, q, exit, <EOF>
	     Exit the program.

SEE ALSO

     editline(3), fs(5), clri(8), fsck(8)

HISTORY

     fsdb uses the source code for fsck(8) to implement most of the file system manipulation code.  The remainder of fsdb first appeared in
     NetBSD 1.1.

WARNING

     Use this tool with extreme caution -- you can damage an FFS file system beyond what fsck(8) can repair.

BUGS

     Manipulation of ``short'' symlinks doesn't work (in particular, don't try changing a symlink's type).
     You must specify modes as numbers rather than symbolic names.
     There are a bunch of other things that you might want to do which fsdb doesn't implement.

BSD
								  January 3, 2004							       BSD