BVI(1)                    User Commands                    BVI(1)


NAME
       bvi, bview - visual display editor for binary files

VERSION
       bvi-1.3.1

SYNOPSIS
       bvi   [-R] [-c cmd] [-f script] file...
       bview [-R] [-c cmd] [-f script] file...

OPTIONS
       file...
           One or more files.  The file argument indicates one or
           more files to be edited.

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

       -c cmd
           Execute command cmd.  Begin editing by executing the
           specified editor command (usually a search or
           positioning command).

       -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 display
       oriented editor for binary files; its command set is based
       on those of the vi(1) texteditor.  As a binary editor
       cannot have the concept of "lines" there are several
       differences to Vi commands (see COMPARISON).

COMPARISON
       The main differences between Vi and Bvi are:

       The screen is divided in three sections/windows: The byte
       offset (at the left side), the hex window (in the middle),
       and the ascii window (to the right) which shows the ascii
       values of those bytes in the hex window.  On an 80 column
       terminal you will therefore see sixteen hex values and
       their ASCII values on each screen line.  Note that the
       first byte has the offset '0' (zero).

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

       No "lines" concept: Files are treated as one long series
       of bytes only.  These characters "newline" and "carriage
       return" thus are not special, ie they do not 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 as they happen to fit in.  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 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 aka Normal Mode:

       Input is treated as commands.  Note that command mode is
       the default mode after startup and when you escape/quit
       from either command line mode or input mode.  Use ESC
       (escape) to cancel a partial (uncompleted) command.

   Input Mode:

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

   Command line mode (aka Last Line Mode):

       Reading input for : / ? \ # or !; terminate by typing a
       carriage return; an interrupt cancels termination.  Type
       ESC to cancel 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!         reedit 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 abandom 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@altavista.net

WWW
       Bvi Homepage:  http://bvi.sourceforge.net/
       Vi Pages:      http://www.math.fu-berlin.de/~guckes/vi/
                      (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/2002             BVI Version 1.3.1                       8
