hexedit

HEXEDIT(1)                   General Commands Manual                  HEXEDIT(1)



NAME
       hexedit - view and edit files in hexadecimal or in ASCII

SYNOPSIS
       hexedit [-s | --sector] [-m | --maximize] [-l<n> | --linelength <n>] [-h
       | --help] [filename]

DESCRIPTION
       hexedit shows a file both in ASCII and in hexadecimal. The file can be a
       device as the file is read a piece at a time. You can modify the file and
       search through it.

OPTIONS
       -s, --sector
              Format the display to have entire sectors.

       -m, --maximize
              Try to maximize the display.

       --color
              Display colors.  This feature is only available if your operating
              system supports it.

       -l<n>, --linelength <n>
              Explicitly set the number of bytes to display per line to <n>.

       -h, --help
              Show the usage.

COMMANDS (quickly)
   Moving
       <, > :  go to start/end of the file
       Right:  next character
       Left:   previous character
       Down:   next line
       Up:     previous line
       Home:   beginning of line
       End:    end of line
       PUp:    page forward
       PDown:  page backward

   Miscellaneous
       F2:     save
       F3:     load file
       F1:     help
       Ctrl-L: redraw
       Ctrl-Z: suspend
       Ctrl-X: save and exit
       Ctrl-C: exit without saving

       Tab:    toggle hex/ascii
       Return: go to
       Backspace: undo previous character
       Ctrl-U: undo all
       Ctrl-S: search forward
       Ctrl-R: search backward

   Cut&Paste
       Ctrl-Space: set mark
       Esc-W:  copy
       Ctrl-Y: paste
       Esc-Y:  paste into a file
       Esc-I:  fill

COMMANDS (full and detailed)
       o Right-Arrow, Left-Arrow, Down-Arrow, Up-Arrow - move the cursor.
       o Ctrl+F, Ctrl+B, Ctrl+N, Ctrl+P - move the cursor.
       o Ctrl+Right-Arrow, Ctrl+Left-Arrow, Ctrl+Down-Arrow, Ctrl+Up-Arrow -
       move n times the cursor.
       o Esc+Right-Arrow, Esc+Left-Arrow, Esc+Down-Arrow, Esc+Up-Arrow - move n
       times the cursor.
       o Esc+F, Esc+B, Esc+N, Esc+P - move n times the cursor.
       o Home, Ctrl+A - go the beginning of the line.
       o End, Ctrl+E - go to the end of the line.
       o Page up, Esc+V, F5 - go up in the file by one page.
       o Page down, Ctrl+V, F6 - go down in the file by one page.
       o <, Esc+<, Esc+Home - go to the beginning of the file.
       o >, Esc+>, Esc+End - go to the end of the file (for regular files that
       have a size).
       o Ctrl+Z - suspend hexedit.
       o Ctrl+U, Ctrl+_, Ctrl+/ - undo all (forget the modifications).
       o Ctrl+Q - read next input character and insert it (this is useful for
       inserting control characters and bound keys).
       o Tab, Ctrl+T - toggle between ASCII and hexadecimal.
       o /, Ctrl+S - search forward (in ASCII or in hexadecimal, use TAB to
       change).
       o Ctrl+R - search backward.
       o Ctrl+G, F4 - go to a position in the file.
       o Return - go to a sector in the file if --sector is used, otherwise go
       to a position in the file.
       o Esc+L - display the page starting at the current cursor position.
       o F2, Ctrl+W - save the modifications.
       o F1, Esc+H - help (show the man page).
       o Ctrl+O, F3 - open another file
       o Ctrl+L - redisplay (refresh) the display (useful when your terminal
       screws up).
       o Backspace, Ctrl+H - undo the modifications made on the previous byte.
       o Esc+Ctrl+H - undo the modifications made on the previous bytes.
       o Ctrl+Space, F9 - set mark where cursor is.
       o Esc+W, Delete, F7 - copy selected region.
       o Ctrl+Y, Insert, F8 - paste (yank) previously copied region.
       o Esc+Y, F11 - save previously copied region to a file.
       o Esc+I, F12 - fill the selection with a string
       o Esc+T - truncate the file at the current location
       o Ctrl+C - unconditional quit (without saving).
       o F10, Ctrl+X - quit.

       For the Esc commands, it sometimes works to use Alt instead of Esc. Funny
       things here (especially for froggies :) egrave = Alt+H , ccedilla =
       Alt+G, Alt+Y = ugrave.

   Modeline
       At the bottom of the display you have the modeline (copied from emacs).
       As in emacs, you have the indications --, ** and %% meaning unmodified,
       modified and read-only. Then you have the name of the file you're
       currently editing. Next to it is the current position of the cursor in
       the file followed by the total file size. The total file size isn't quite
       correct for devices.
       While in --sector mode, it shows the sector the cursor is in.

   Editing
       You can edit in ASCII or in hexadecimal. You can switch between the two
       with Tab. When the file is read-only, you can't edit it. When trying to
       edit a read-only file, a message "File is read-only" tells you it is non-
       writable.
       The modifications are shown in bold until they are saved.  The modeline
       indicates whether you have modified the file or not.
       When editing in hexadecimal, only 0,1,...,9, a,b,...,f, A,B,...F are
       legal.  Other keys are unbound. The first time you hit an unbound key,
       the help pops up.  It won't pop again unless you call the help directly
       (with F1).
       When editing in ascii, you can find it difficult to enter characters like
       / which are bound to a function. The solution is to use the quoted insert
       function Ctrl+Q, the key after the quoted insert function is not
       processed by hexedit (like emacs' quoted-insert, or like the \ character
       in C).

   Searching
       You can search for a string in ASCII or in hexadecimal. You can switch
       between the two with Tab. If the string is found, the cursor is moved to
       the beginning of the matching location. If the search failed, a message
       "not found" tells you so. You can cancel the search by pressing a key.
       The search in hexadecimal is a bit confusing. You must give a hexadecimal
       string with an even number of characters. The search can then be done
       byte by byte. If you want to search a long number (eg: a 32 bit number),
       you must know the internal representation of that number (little/big
       endian problem) and give it the way it is in memory. For example, on an
       Intel processor (little endian), you must swap every bytes: 0x12345678 is
       written 0x78563412 in memory and that's the string you must give to the
       search engine.
       Before searching you are asked if you want to save the changes, if the
       file is edited.

       For more sophisticated search, see Volker Schatz's patch at
       <http://www.volkerschatz.com/unix/homebrew.html#hexedit>.

   Selecting, copying, pasting, filling
       First, select the part of the buffer you want to copy: start setting the
       mark where you want. Then go to the end of the area you want to copy (you
       can use the go to function and the search functions). Then copy it. You
       can then paste the copied area in the current file or in another file.

       You can also fill the selected area with a string or a character: start
       choosing the block you want to fill in (set mark then move to the end of
       the block), and call the fill function (F12). hexedit ask you the string
       you want to fill the block with.
       The code is not tuned for huge filling as it keeps the modifications in
       memory until you save them. That's why hexedit will warn you if you try
       to fill in a big block.

       When the mark is set, the selection is shown in reverse mode.
       Be aware that the copied area contains the modifications done at the time
       of the copy. But if you undo the modifications, it does not change the
       content of the copy buffer. It seems obvious but it's worth saying.

   Scrolling
       The scrolling is different whether you are in --sector mode or not. In
       normal mode, the scrolling is line by line. In sector mode, the scrolling
       is sector by sector. In both modes, you can force the display to start at
       a given position using Esc+L.

SEE ALSO
       od(1), hdump(1), hexdump(1), bpe(1), hexed(1), beav(1).

AUTHOR
       Pixel (Pascal Rigaux) <pixel@rigaux.org>,
       Home page is <http://rigaux.org/>.

UNRESTRICTIONS
       hexedit is Open Source; anyone may redistribute copies of hexedit to
       anyone under the terms stated in the GNU General Public License.

       You can find hexedit at
       <https://github.com/pixel/hexedit/archive/1.5.tar.gz>

TODO
       Anything you think could be nice...

LIMITATIONS
       There are problems with the curses library given with Redhat 5.0 that
       make hexedit think the terminal is huge. The result is that hexedit is
       not usable.

       The shortcuts work on some machines, and not on others. That's why there
       are many shortcuts for each function. The Ctrl+Arrows and the Alt+. do
       not work work as they should most of the time. On SUNs, you must do
       Ctrl+V-Ctrl+V instead of Ctrl+V (!); and the Alt key is the diamond one.

       While searching, it could be interesting to know which position the
       search has reached. It's always nice to see something moving to help
       waiting.

       The hexadecimal search could be able to search modulo 4 bits instead of 8
       bits.  Another feature could be to complete padd odd length hexadecimal
       searches with zeros.

BUGS
       I have an example where the display is completely screwed up. It seems to
       be a bug in ncurses (or maybe in xterm and rxvt)?? Don't know if it's me
       using ncurses badly or not... It seems to happen when hexedit leaves only
       one space at the end of the lines... If anyone has a (or the) solution,
       please tell me!

       If you have any problem with the program (even a small one), please do
       report it to me. Remarks of any kind are also welcome.

                                  12 July 1998                        HEXEDIT(1)