    BVI(1)                    User Commands                    BVI(1)

    NAME
           bvi, bview - visual editor for binary files

    VERSION
           bvi-1.3.2

    SYNOPSIS
           bvi   [-R] [-c cmd] [-f script] [-b begin] [-e end] [-s size] file...
           bview [-R] [-c cmd] [-f script] [-b begin] [-e end] [-s size] file...

    OPTIONS
           file...
               A  list  of  filenames.  The first one will be the
               current file and will be read into  the  buffer.  The
               cursor  will  be  positioned on the first line of the
               buffer.  You can get to the other files with the
               ":next" command.

           -R  "Readonly": The readonly flag is set for all the
               files, preventing accidental overwriting with a write
               command.

           -b begin
               causes bvi to load a file not from the start but from
               offset begin.

           -e end
               causes bvi to load a file not till end but till
               address end.

           -s size
               causes bvi not to load the complete file but only size
               bytes.

           -c cmd
               cmd will be  executed  after  the  first file  has
               been read. If the  cmd  contains spaces  it  must  be
               enclosed in double quotes (this depends on  the  shell
               that  is  used).

           -f script
               This command provides a means for collecting a series
               of "ex" (colon) commands into a script file, then
               using this file to edit other files. Since there is no
               binary stream editor "bsed", you can use this option
               to make several global changes in a binary file.

    DESCRIPTION
           Bvi stands for "Binary VIsual editor".  Bvi is a screen
           oriented editor for binary files; its command set is based
           on that of the vi(1) text editor.  As a binary editor does
           not have the concept of "lines" there are differences from
           Vi commands wherever the latter are line orientate.

    COMPARISON
           The main differences between Vi and Bvi are:

           The screen is divided in three sections or panes: The byte
           offset (extreme left), the hex pane (middle), and an ascii
           pane (right) which shows as printable characters those
           bytes in the hex pane.  On an 80 column terminal there
           will be sixteen hex values and their ASCII values on each
           screen line.  Note that (as one would expect) the first
           byte has the offset '0' (zero).

           You can toggle between the hex and ascii windows with the
           tab key (TAB).  Toggling between these two windows does
           not change the current position (offset) within the file.

           No "lines" concept: Files are treated as one long stream
           of bytes.  The characters "newline" and "carriage return"
           are not special, id est they never mark the end of lines.
           Therefore the lines on the screen do not represent lines
           in the usual way.  Data is broken across screen lines
           arbitarily.  As a consequence there are no commands in bvi
           from ex or vi that are based on line numbers, eg "dd",
           "yy", 'C', 'S', 'o', 'O'.  This also changes the meaning
           of "range" before the ":write" command to a byte offset,
           ie the command ":100,200w foo" writes all *bytes* (not
           lines) from offset 100 to offset 200 to the file "foo".

           No "text objects": There are also no text-specific
           arrangements like words, paragraphs, sentences, sections
           and so on.

           Extended "ruler": The bottom line of the screen shows the
           current address (byte offset) and the current character in
           these notations:

                   octal, hexadecimal, decimal and ascii.

           Search patterns: All search commands understand these
           special characters:

                .    any character
                []   set of characters
                *    zero or more occurrences of previous char or set

           But as there is no concept of lines you cannot use the
           standard symbols ("anchors") for "begin-of-line" ('^') and
           "end-of-line" ('$').  Searching for the start/end of lines
           must be done explicitly by adding these special characters
           to your search pattern using these meta sequences:

                   \n   newline
                   \r   return
                   \t   tab
                   \0   binary zero

           Additional search commands: Similar to the text search
           commands there are additional hex-search functions '\' and
           '#' which allow to search for any byte value.  Example:
           "\62 76 69" will search for the string "bvi".  Spaces
           between hex value are optional, so searching for
           "6775636B6573" will find "guckes".

           Changing the length of data (insertion, deletion) moves
           the data to other addresses; this is bad for many cases
           (eg. databases, program files) and is thus disabled by
           default. You can enable this commands by typing

                :set memmove

           BVI Modes:

           Command Mode (Normal Mode):

           Input is treated as command.  Note that command mode is
           the default mode after startup and after escaping from
           input mode.  Use ESC (escape) to cancel a partial
           (uncompleted) command.

           Input Mode:

           Input is treated as replacement of current characters or
           (after the end of the file) is appended to the current
           file.  This mode is entered from command mode by typing
           one of 'i', 'I', 'A', 'r', or 'R'.  You can enter the
           characters from the keyboard (in the ASCII window) or
           hexadecimal values (in the HEX window).  Type TAB to
           switch between these two windows.  Type ESC to finish the
           current input and return to command mode.  Type CTRL-C to
           cancel current command abnormally.

           Command line mode (Last Line Mode or : mode):

           Similar to vi, this mode is entered by typing one of the
           characters : / ? \ # !  The command is terminated and
           executed by typing a carriage return; to cancel a
           partially typed command, type ESC to cancel the current
           command and return to command mode.

    ENVIRONMENT
           The editor recognizes the environment variable BVIINIT as
           a command  (or  list of commands) to run when it starts
           up. If this variable is undefined, the editor  checks  for
           startup commands  in  the  file  ~/.bvirc  file, which you
           must own.  However, if there is a .bvirc owned by you  in
           the  current directory,  the  editor takes its startup
           commands from this file - overriding both the file in your
           home  directory  and the environment variable.

    TERMINOLOGY
           Characters names are abbreviated as follows:
                Abbr.     ASCII     name      aka
                CR        010       carriage return
                ^A        001       control-a
                ^H        008       control-h
                ^I        009       control-i      aka TAB
                ^U        021       control-u
                ^Z        026       control-z
                ESC       027       escape         aka ESC
                DEL       127       delete
                LEFT      ---       left  arrow
                RIGHT     ---       right arrow
                DOWN      ---       down  arrow
                UP        ---       up    arrow

    COMMAND SUMMARY
           See the TERMINOLOGY for a summary on key name
           abbreviations used within the following description of
           commands.

           Abstract:
             Arrow keys move the cursor on the screen within the
           current window.

           Sample commands:
             :version    show version info
             <- v ^ ->   arrow keys move the cursor
             h j k l     same as arrow keys
             u           undo previous change
             ZZ          exit bvi, saving changes
             :q!         quit, discarding changes
             /text       search for text
             ^U ^D       scroll up or down

           Counts before bvi commands:
             Numbers may be typed as a prefix to some commands.
             They are interpreted in one of these ways.

             screen column       |
             byte of file        G
             scroll amount       ^D  ^U
             repeat effect       most of the rest

           Interrupting, canceling
             ESC         end insert or incomplete command
             DEL         (delete or rubout) interrupts

           File manipulation:
             ZZ          if file modified, write and exit;
                         otherwise, exit
             :w          write changed buffer to file
             :w!         write changed buffer to file, overriding
                         read-only ("forced" write)
             :q          quit when no changes have been made
             :q!         quit and discard all changes
             :e file     edit file
             :e!         re-read current file, discard all changes
             :e #        edit the alternate file
             :e! #       edit the alternate file, discard changes
             :w  file    write current buffer to file
             :w! file    write current buffer to file overriding
                         read-only (this "overwrites" the file)
             :sh         run the command as set with option "shell",
                         then return
             :!cmd       run the command cmd from "shell", then
                         return
             :n          edit next file in the argument list
             :f          show current filename, modified flag,
                         current byte offset, and percentage of
                         current position within buffer
             ^G          same as :f

           Additional edit commands
             You can insert/append/change bytes in
           ASCII/binary/decimal/ hexadecimal or octal representation.
           You can enter several (screen) lines of input. A line with
           only a period (.) in it will terminate the command. You
           must not type in values greater than a byte value. This
           causes an abandonment of the command.  Pressing the CR key
           does not insert a newline - character into the file. If
           you use ASCII mode you can use the special characters \n,
           \r, \t and \0.

             :i aCR      insert bytes (ASCII) at cursor position
             :a bCR      append bytes (Binary) at end of file
             :c hCR      change bytes (hexadecimal) at cursor position

           Bit-level operations
             :and n      bitwise 'and' operation with value n
             :or  n      bitwise 'or' operation with value n
             :xor n      bitwise 'xor' operation with value n
             :neg        two's   complement
             :not        logical negation
             :sl i       shift  each byte i bits to the left
             :sr i       shift  each byte i bits to the right
             :rl i       rotate each byte i bits to the left
             :rr i       rotate each byte i bits to the right

           Command mode addresses
             :w foo         write current buffer to a file
                            named "foo"
             :5,10w foo     copy byte 5 through 100 into as
                            file named foo
             :.,.+20w foo   copy the current byte and the next
                            20 bytes to foo
             :^,'aw foo     write all bytes from the beginning
                            through marker 'a'
             :/pat/,$ foo   search pattern pat and and copy
                            through end of file

           Positioning within file:
             ^B      backward screen
             ^F      forward  screen
             ^D      scroll down half screen
             ^U      scroll up   half screen
             nG      go to the specified character
                     (end default), where n is a decimal address
             /pat    next line matching pat
             ?pat    previous line matching pat
             \hex    jump to next     occurrence of hex string hex
             #hex    jump to previous occurrence of hex string hex
             n       repeat last search command
             N       repeat last search command, but in opposite
                     direction

           Adjusting the screen:
             ^L      clear and redraw screen
             zCR     redraw screen with current line at top of screen
             z-      redraw screen with current line at bottom of
                     screen
             z.      redraw screen with current line at center of
                     screen
             /pat/z- search for pattern pat and then move currents
                     line to bottom
             ^E      scroll screen down 1 line
             ^Y      scroll screen up   1 line

           Marking and returning:
             mx      mark current position with lower-case letter x
                     Note: this command works for all lower-case
           letters
             'x      move cursor to mark x in ASCII section
             `x      move cursor to mark x in HEX section
             ''      move cursor to previous context in ASCII section
             ``      move cursor to previous context in HEX section
           Line positioning:
             H           jump to first      line on screen ("top")
             L           jump to last       line on screen ("low")
             M           jump to middle     line on screen ("middle")
             -           jump onto previous line on screen
             +           jump onto next     line on screen
             CR          same as +
             DOWN or j   next     line, same column
             UP   or k   previous line, same column

           Character positioning:
             ^           first byte in HEX window
             $           end of screen line
             l or RIGHT  jump onto next byte (within current
                         screen line)
             h or LEFT   jump onto previous byte (within current
                         screen line)
             ^H          same as LEFT
             space       same as RIGHT
             fx          find next     occurrence of character x
             Fx          find previous occurrence of character x
             n|          jump onto nth byte/character within current
                         line

           Strings:
             (works similar to the strings(1) command)
             Note:  "Words" are defined as strings of "nonprinting
             characters".
             e       jump to next     end   of word
             w       jump to next     begin of word
             b       jump to previous begin of word
             W       forward to next string delimited with a
                     \0 or \n
             B       back to previous string delimited with a
                     nonprinting char
           Corrections during insert:
             ^H      erase last character (backspace)
             erase   your erase character, same as ^H (backspace)
             ESC     ends insertion, back to command mode

           Append and replace:
             A       append at end of file
             rx      replace current bte with char 'x'
             R       enter replace mode; for all subsequent input,
                     the current byte is overwritten with the next
                       input character; leave replace mode with ESC.

           Miscellaneous Operations:
             TAB     toggle between ASCII and HEX section

           Yank and Put:
             3ySPACE yank 3 characters
             p       insert contents of yank buffer
             o       replace text with content of yank buffer
             P       put back at end of file

           Undo, Redo:
             u       undo last change
                     Note:  Only the last change can be undone.
                     Therefore this commands toggles between the
                     last and second-t-last state of the buffer.

           Setting Options:
             With the :set command you can set options in bvi

             Option     Default  Description

             autowrite  noaw     Save current file, if modified, if you
                                 give a :n, :r or ! command
             columns    cm=16    on an 80 character wide terminal
             ignorecase noic     Ignores letter case in searching
             magic      nomagic  Makes . [ * special in patterns
             memmove    nomm     enables insert and delete commands
             offset     of=0     adds an offset to the diplayed addresses
             readonly   noro     If set, write fails unless you use ! after command
             scroll     sc=1/2 window
                                 Number of lines scrolled by ^U and ^D
             showmode   mo       Displays statusline on bottom of the screen
             terse      noterse  Let you obtain shorter error messages
             window     window=screensize
                                 Lines in window, can be reduced at slow terminals
             wordlength wl=4     Length of an ASCII-string found by w, W, b or B
             wrapscan   ws       Searches wrap around past the end of the file
             unixstyle  nous     The representation of ascii characters below
                                 32 is displayed in the statusline as shown
                                 in ascii(7) if unset rather in DOS-style (^A)

    AUTHOR
           bvi was developed by Gerhard Buergmann, Vienna, Austria
           Gerhard.Buergmann@puon.at

    WWW
           Bvi Homepage:  http://bvi.sourceforge.net/
           Vi Pages:      http://www.guckes.net/vi/clones.php3
                          (all about Vi and its clones)

    FILES
            $HOME/.bvirc          editor startup file
            ./.bvirc              editor startup file

    BUGS
           Bvi does not update the screen when the terminal changes
           its size.

    SEE ALSO
           vi(1), strings(1), ascii(5)

    3/Jan/2004              BVI Version 1.3.2