Dump Instructions

The hex dump program takes a file and returns it in both ascii and numeric format. It works best with files that are mostly characters. For true data files the results are harder to read since some of the bytes may contain control characters.

The three fields you enter are:

The display itself will look like this for a hexidecimal dump::

 F  r  o  m  :     J  d  o  e //    
46 72 6f 6d 3a 20 4a 64 6f 65 //
 S  e  n  t  :     W  e  d  n  e  s  d  a  y  ,     J  a  n 
53 65 6e 74 3a 20 57 65 64 6e 65 73 64 61 79 2c 20 4a 61 6e  
 a  r  y     2  9  ,     2  0  0  3     3  :  2  5     P  M 
61 72 79 20 32 39 2c 20 32 30 30 33 20 33 3a 32 35 20 50 4d  
 T  o  :     P  a  u  l     C  h  a  p  i  n //    
54 6f 3a 20 50 61 75 6c 20 43 68 61 70 69 6e //
 S  u  b  j  e  c  t  :     R  E  :     t  e  s  t //    
53 75 62 6a 65 63 74 3a 20 52 45 3a 20 74 65 73 74 //
// 
//
 I     h  a  v  e     n  o  t  h  i  n  g     t  o     s  a 
49 20 68 61 76 65 20 6e 6f 74 68 69 6e 67 20 74 6f 20 73 61     
    t  o     y  o  u  . //    
20 74 6f 20 79 6f 75 2e //
//
//

In this case the width was set to 20. The double slash, //, at the end of some lines indicates a newline character (hex value of d, decimal 13). Where the slashes are on a line by themselves, this indicates a blank line.

For other values less that 32 (20 hex) no text value is displayed since many of these values are control characters that would mess up the data transfer. In these cases, the top line, which normally contains the text, contains the same numeric value as the line below. For example, the following line contains only two characters followed by a newline,

 0  00 //
30 00 //

The first character in the file is a hexidecimal 30 which is the code for the number 0. The second character is a hexidecimal 0. Since this is less that 20 hex, we display the two digit code on both lines. Only numeric values will appear as two digits on both lines and only characters with values less than 20 hex will appear the same on both lines.

Remember that hex 20 (decimal 32) is a space character so nothing will appear on the top line.

This program uploads your file to the server in order to do the dump. The file is not retained, is not used for anything but to create the dump, and is not examined by anyone. However, the upload process itself it not particularly secure and in case of systems problems I can not promise the privacy of your file.

Created by Paul Chapin, pdchapin@amherst.edu, in February, 2003.

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