BDUMP - Binary File Dumper
 
 
                        Kelvin Smith
              Financial Computer Systems, Inc.
 
 

     The binary dump facilities provided by DEC have, to  my
mind,  a  number of disadvantages.  The accompanying program
was designed to  overcome  those  problems,  and  offer  the
greatest possible flexibility in getting bit/byte level data
on files.  While written for RSTS, BDUMP can be converted to
other systems with BASIC language facilities (such as VMS or
RSX) simply by adjusting the two SYS calls,  at  lines  2050
and 30000, to the proper equivalents in the other system for
getting a full filespec and  getting  a  DCL  command  line,
respectively.
 
                           Output

     BDUMP displays the contents  of  a  data  file  in  two
forms:  numeric and character.  The numeric format may be by
bytes or words, in octal or decimal.  The character data  is
shown at the end of the line:  All ASCII printing characters
are reproduced as they exist in the file, while nulls (ASCII
0)  are  reproduced  as  underscores  (_)  and other control
characters (ASCII 1-31, 127-159, and 255) are reproduced  as
dots  (.).   A  line  contains  either  8  bytes (for normal
byte-by-byte displays) or 16  bytes  (for  word-by-word  and
wide byte-by-byte displays).

     At the start of  each  block,  BDUMP  prints  a  header
indicating  the  full  filespec of the file being dumped and
the block number.  The  block  number  is  always  shown  in
decimal;   if  the  numeric  display  is in octal, the block
number is also shown in  octal.   Note,  however,  that  the
octal  block  number  is  actually one less than the decimal
block number.  This is for  compatibility  with  ODT,  which
starts  numbering  its  addresses at 0.  Combining the octal
block number and the octal offset (shown at the beginning of
each  line) gives the proper address for ODT.  (Example:  If
the block number is 000002 and the offset within  the  block
for the byte you want is 340, the ODT address is 2340.)

     Each line starts with the offset of the first  byte  of
that   line,  in  decimal  if  decimal  numbering  has  been
requested, otherwise in octal.  If character display only is
requested  via  the  /A  option (see below), the offsets are
shown in decimal.
 
                      The command line

     BDUMP may be run either as a program or  as  a  CCL/DCL
command.  If you run BDUMP or give the BDUMP command without
any argument, the program responds with a  "BDUMP>"  prompt,
at which you may specify a command line.

                    
                                                      Page 2



     The command line should be in the form:
 
          [[outfile] =] infile [/options]
 
If neither "outfile" nor "=" is specified, output is to  the
terminal.   Specifying "=" without an output filespec causes
output to go to infile.LST.  If the output filespec does not
include a filetype, .LST is used.

     Any number of options may be specified together;   each
should  start  with  a  slash.   The  following  options are
available:
 
/A    ASCII character output only;  no  numeric  representa-
      tion of the data (64 bytes per line).
/B    Show numeric data by bytes (8 bytes per line).
/D    Show numeric data in decimal (default is octal).
/E:n  End the dump after displaying block n.
/S:n  Start the dump with block n.
/W    Show numeric data by bytes, 16 bytes across (this wide
      display requires 87 columns).
/H    Help message (no file  need  be  specified;   you  are
      returned to the BDUMP> prompt).
 
                       Miscellaneous

     Although this program is believed to work as described,
it  is being provided as a service to the DEC community, and
no warranty, express  or  implied,  is  made  regarding  its
functions  or  fitness  by either the author or his company.
Please report any bugs or suggestions for improvements to:
 
Kelvin Smith
Financial Computer Systems, Inc.
1 Strawberry Hill Ct.
Stamford, CT  06902
(203) 357-0504