[MACTCL] Writing Binary Data to a File

[Mark A J. <maj...@ra...>]

All,

This is NOT a MAC question, but I have not been able to find help with this
on the internet and I thought I'd ask my question here and hopefully
someone could answer my question.

I am reading binary data from a file in a specific order and then I want to
write the data IN BINARY FORM to an output file.

[begin code snippet]
--------------------
set my_binary_data "";
set in_file_id [ open my_binary_file r ];
set out_file_id [ open my_output_file w ];

loop starts here ...
  set offset { someplace in the binary file };
  seek $in_file_id $offset start;               # go to the data in the
file
  binary scan [ $in_file_id  1 ] H2 data_piece; # read binary data in HEX
  append my_binary_data $data_piece;            # appends just read binary
                                                #   data to what what
                                                #   previously read and
                                                #   appended
end loop ...

puts -nonewline $out_file_id "$my_binary_data"; # write string of extracted
                                                #   binary data to a file

close $in_file_id;
close $out_file_id;
-------------------
[end code snippet]

I am reading the binary data file and extracting the correct data, but when
I write the data to a file ... it is being written in ASCII ... NOT in
binary ... i.e., if I read '8e' ... I want to write '8e' to my file, but
what is happening is  ... '3865' is being written to my output file.

38 is ASCII for 8
65 is ASCII for e

Any help would be appreciated. I have verified this is happening because I
am looking at the file with a BINARY EDITOR.

btw, fyi ... I am trying to run this tcl code on a PC running LINUX 8.0.

TIA,
Mark