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      1 ext2ed - The extended-2 filesystem editor, version e2fsprogs
      2 
      3 
      4 This version of ext2ed has been modified and updated by Theodore Ts'o
      5 for inclusion with the e2fsprogs package.  It now builds with modern
      6 ncurses and I've fixed various small bugs, particular in the redrawing
      7 and resizing functions.
      8 
      9 It is currently not built by default -- the top-level e2fsprogs
     10 Makefile doesn't recurse into this directory.  This is because ext2ed
     11 has a number of VERY SERIOUS shortcomings:
     12 
     13 1)  It doesn't work on filesystems bigger than 2GB
     14 
     15 2)  It assumes that all's the world an Intel, and assumes that
     16 	everything is in Intel (little-endian) byte order.
     17 
     18 Fixing either of these problems would be non-trivial, and so I at this
     19 point DO NOT RECOMMEND that distributions try to include this program,
     20 even as modified and updated in e2fsprogs.  This especially goes for
     21 Debian, where the Debian maintainer for e2fsprogs has a history of
     22 making authorized changes to e2fsprogs to include programs that aren't
     23 supported, and then starts bugging me with bug reports.  YES I KNOW.
     24 THIS PROGRAM HAS HORRIBLE SHORTCOMINGS.  IT IS INCLUDED HERE ONLY
     25 BECAUSE IT'S A CONVENIENT WAY FOR (FOR E2FSPROGS DEVELOPERS ON INTEL
     26 MACHINES) TO GENERATE TEST CASES BY SELECTIVELY CORRUPTING
     27 FILESYSTEMS.  I WILL NOT SUPPORT THIS PROGRAM FOR USE BY GENERAL USERS
     28 SO PLEASE DO NOT INCLUDE IT IN A DISTRIBUTION.
     29 
     30 I have currently disabled the use of GNU Readline in this program,
     31 because readline and ncurses really don't play well together at all.
     32 Readline assumes that it can write arbitrary text to the screen
     33 (especially when it tries to print out a completion list), which just
     34 doesn't work with ncurses.  Fixing this so they would work together
     35 would require wholesale changes to readline.   
     36 
     37 				Theodore Ts'o
     38 				tytso (a] MIT.EDU
     39 				May 12, 2001
     40 
     41 ----------------------------------------------------------------------------
     42 
     43 ext2ed - The extended-2 filesystem editor, version 0.2
     44 ------------------------------------------------------
     45 
     46 This is version 0.2 of ext2ed - The extended-2 filesystem editor.
     47 
     48 Modifications on Apr 5 2001
     49 This is minor bug fixes to ext2ed, as of April 2001.
     50 It supports modern ext2 version that has file type in directory structure
     51 and fixes the missunderstanding between ncurses and
     52 readline.
     53 
     54 I first applied patches from Redhat except the one for readline that 
     55 rewrote a readline behavior.
     56 
     57 Globals diffs between version 0.1 and 0.2 is stored in file :
     58 	diff-ext2ed.1.2
     59 
     60 Christian Bac <Christian.Bac (a] nt-evry.fr>
     61 
     62 ----------------------------------------------------------------------------
     63 
     64 Documentation
     65 -------------
     66 
     67 ext2ed's documentation consists of three documents:
     68 
     69 1.	The user's guide.
     70 2.	Technical overview of the ext2 filesystem.
     71 3.	The EXT2ED design and implementation document.
     72 
     73 Those documents are available in the doc directory, in linuxdoc-sgml and
     74 postscript formats.
     75 
     76 The documentation is also available online at:
     77 
     78 http://tochnapc2.technion.ac.il
     79 
     80 under the ext2ed section.
     81 
     82 Installation
     83 ------------
     84 
     85 ext2ed requires the kernel sources and the readline and ncurses packages.
     86 Please edit the makefile if you are using an "old" version of ncurses (See the
     87 details below) or if gcc can't find the various header files and libraries.
     88 
     89 To install, simply issue a 'make' command to compile and a 'make install'
     90 command to install. I have also included an already compiled linux a.out
     91 binary.
     92 
     93 ext2ed and ncurses
     94 ------------------
     95 
     96 ext2ed uses the ncurses library for terminal output. It is very important
     97 that ncurses will be properly installed on your system:
     98 
     99 1.	Old versions of ncurses (around 1.8.5) need the OLD_NCURSES compile
    100 	time option in EXT2ED.
    101 
    102 	At least from 1.9.2c, this flag should not be used. I would recommend
    103 	upgrading the ncurses library to the newer versions.
    104 
    105 2.	ncurses uses its own terminfo database rather then the termcap file.
    106 	It is important that the terminfo database will be found by ncurses.
    107 	If this is not the case, you will see on startup some lines which
    108 	refer to /etc/termcap. This will mean that there is a problem with
    109 	the terminfo database.
    110 
    111 3.	Newer versions of ncurses (and the 1.3 series of the kernel) describe
    112 	the linux console in the entry 'linux' and not 'console', as it was
    113 	before. If you run ext2ed in the linux console, you should either
    114 	set your TERM environment variable to 'linux' or link
    115 	l/linux to c/console in the terminfo database.
    116 
    117 4.	The percompiled binary was linked with ncurses 1.9.4 and will search
    118 	for the terminfo database on /usr/local/lib/terminfo. If you are
    119 	using it, and your 1.9.4 compatible terminfo database is not on the
    120 	directory above, use the TERMINFO environment variable to specify
    121 	an alternate location.
    122 
    123 Running ext2ed
    124 --------------
    125 
    126 For those of you who don't like reading lengthy articles, here are a few
    127 basic guidelines:
    128 
    129 1.	Don't use ext2ed to change a mounted filesystem !
    130 
    131 	Using ext2ed in read-only mode on a mounted filesystem can be allowed
    132 	by using the configuration file option 'AllowMountedRead on'. However,
    133 	note that the displayed data will be unreliable.
    134 
    135 2.	ext2ed currently can't handle filesystems bigger than 2 GB. I am
    136 	sorry for the inconvenience. This will hopefully be fixed in future
    137 	releases.
    138 
    139 3. 	Before running ext2ed, edit the configuration file
    140 	/var/lib/ext2ed/ext2ed.conf to suit your needs. The various
    141 	configuration options are documented there.
    142 
    143 4.	Use the 'setdevice' command to open an ext2 filesystem.
    144 	e.g. 'setdevice /dev/hda1'.
    145 
    146 5.	If the filesystem is an ext2 filesystem and ext2ed fails to
    147 	autodetect this, use the 'ForceExt2 on' configuration file option.
    148 
    149 6.	The filesystem will always be opened in read-only mode. Feel free to
    150 	experiment, but take care with the 'enablewrite' command.
    151 
    152 -----------------------------------------------------------------------------
    153 
    154 Feel free to send me feedback with anything regarding to ext2ed.
    155 
    156 Enjoy,
    157 
    158 Gadi Oxman <tgud (a] tochnapc2.technion.ac.il>
    159 Haifa, August 23 1995
    160 
    161