Overview of HexDump

HexDump allows you to view any file in hexadecimal and ASCII. It also provides simple editing capabilities - insert, delete, replace, cut, copy, paste, find and replace. You can undo up to 100 editing changes. You can search for strings in either hex or ASCII, or go to a specified offset (number of bytes) in the file. Printing is supported, and you can select the font size.

Each line in a window displays the location within the file (number of bytes from start of file) of the first byte on that line, in hexadecimal (base 16) notation; 16 bytes in hexadecimal, and the same 16 bytes in ASCII (regular characters). Non-printing characters, including carriage returns and linefeeds, are displayed as a period in the ASCII subwindow. Characters in extended character sets (high bit set), such as accented characters in French, are also displayed as a period in the ASCII subwindow. However, the current character (where the cursor is) is displayed in the status bar of the child window, and this does display extended single byte characters.

There is a scrollbar on the right for navigating through the file. Shortcut keys - PageUp, PageDown, ArrowUp, ArrowDown - work as expected to change which portion of the file is visible. But note that the arrow keys do not move the cursor, you can position the cursor only with the mouse.

HexDump uses the Microsoft MDI paradigm, consisting of multiple child windows within a single main frame. This allows you to view different files at the same time, and to have multiple views of the same file.

Operating System

HexDump requires 32-bit Windows. It has been tested on Win98, Win2000, WinXP, and Vista. It should run on WinNT and Me as well. It should also run on Win95, but you may need to have DCOM installed, and you need Internet Explorer 4 or newer to access the help pages.

The code was developed under Microsoft Visual C++ 6.0. The help screens were developed using Microsoft Help Workshop.

Starting HexDump

Double-clicking on HexDump.exe (in Windows Explorer) or on a shortcut to it brings up the main window. From there you can select File/Open from the menu, or click on the Open icon in the toolbar, to open an existing file.

You can also drag a file from Windows Explorer to the main frame, it will then open. Similarly, you can drag a file from Explorer to the shortcut icon, and HexDump will open with that file opened in it.

You can also open a new, blank file for editing, and save it when you're done.

Command Line Options: You can specify the display font size with a parameter of the form -f10 for 10-point font. Font sizes must be between 6 and 18. Similarly, -fp10 sets the printer font size to 10 points. The first remaining word in the command line is interpreted as the name of the file to open.


You may exit the program by clicking the X at the top right of the window, by clicking Close on the System Menu (magnifying glass at the top left), or by select File/Exit from the menu. In all cases, if files have been edited but not saved, you will be given a chance to save them.


Please report bugs to support@pmansbach.com. We cannot promise support, but we'll try to be of help. We hope to fix reported bugs in subsequent releases. But if you don't tell us, we won't know to fix it!

Legal Disclaimer

This program is provided free, as is, with no warranty whatsoever.

There is no malicious code, no spyware, and no advertising in this code.

The program was developed by Peter Mansbach and paid for by Syntek Systems Corp, Gaithersburg MD, which owns the code.


Note that some menus are not present until a file is opened. Also, some menu selections are grayed out when they are not available. For example, File/Save is not available until a change has been made to the file.

Clicking on a menu selection applies it to the "active" subwindow. The active subwindow is the one you last clicked on. It has a different color title bar.

Some menu items are directly accessible from the toolbar. These are described in the Toolbar section of this help file. Some menu items have keyboard shortcuts. These are described in the Shortcuts section, and appear in the drop down menus as well. Where possible, the standard Microsoft keyboard shortcuts have been used.

File Menu

Open a new, empty, untitled file.
Select an existing file to open.
Close the active subwindow. If that is the last open subwindow for that file, the file is removed from memory. If that is the last open subwindow for that file, and the file has been edited, you will be asked if you want to save it first, before it is removed from memory.
Save the file under its current name, overwriting the previous version. If this is the first time you are saving this file, you will be warned of the overwrite, and be given the opportunity to cancel the save.

Note that when a file has been edited since its last save, an asterisk appears in the title bar.

Save As
Save the active file under a different name, or to a different directory.
Print the currently active file. You will be given an opportunity to select the printer, and to select only some of the pages, or the highlighted section, to print. The default (if you don't change anything) is to print the whole file to the default printer. You will be warned if the file is large.

The printout looks much like the screen: the location within the file on the left of each line, hexadecimal values in the center, and ASCII on the right.

You can change the font size for printing in the View Menu.

Print Preview
See on screen how the printout will look.
Print Setup
Select the printer to use and its properties. You can do this also from
Recently Used Files
The eight most recently opened files appear here, for quick access.
Shut down the program. If any files have been edited, you will be asked if you want to save them first.

Edit Menu

Note that edits (cut, copy, paste, insert, replace, delete) can be performed equally in either the hex section of the subwindow or the ASCII section, there is no difference in the end result. Both sections are updated, and all subwindows open to the same file are updated with the change.
Undo the last editing command that changed something in the file. These commands are cut, paste, insert, replace, and delete. Copy cannot be undone, nor can cursor or highlight changes, or moving where you are in the file. Note that undoing a cut does not restore the clipboard contents, only the changes to the file.

You can undo multiple changes, up to 100 of them. Even if you have saved the file after some of the changes, you can still undo them.

NOTE: If you do a global replace, each replacement counts as one change. YOU CANNOT UNDO MORE THAN THE LAST 100 CHANGES. We hope to remove this restriction in a future release.

Undo affects all subwindows that are open on the same file.

If you undo your way back to the original file contents, and have not saved in between, the file modified indicator (asterisk in the subwindow's title bar) will go away, and you will not be prompted to save the file on exiting, unless you then make more changes. If you have saved the file already, that will not happen.

If you have undone a series of editing changes, you can redo them, one at a time, in reverse order (that is, the most recently undone change is the first to be redone). Once you make another editing change, however, you lose the redo information.
Remove the highlighted content from the file and place it on the clipboard.

You highlight a section by dragging the mouse cursor across it.

HexDump uses the system clipboard, and ASCII characters can be cut, copied, or pasted between different applications. Non-ASCII characters, however, are saved in a special format in HexDump, and cannot be pasted into other applications. But they can be pasted into other HexDump windows.

Copy the highlighted content from the file to the clipboard. See details under Cut.
Paste the contents of the clipboard into the file at the location of the cursor, or in place of the currently highlighted selection. See details under Cut.
Insert a specified string into the file at the cursor, or before the highlighted selection. You will be prompted for the string, and can enter it in ASCII or hexadecimal. Simply click the button labelled ASCII or Hex on the prompting form.

The form will remember your last entry, to simplify making the same change in multiple locations in the file.

As with most Windows programs, the file itself is not modified until you save your changes. If you attempt to exit without saving, a popup will ask if you wish to save.

Like Insert, except that the selection will be removed from the file and replaced with the specified string. See also Find and Replace, below.
The selection will be deleted. It is not copied to the clipboard.
Find and Replace
Search for the next occurrence of a string, and replace it with another string. A dialog box will request that you enter the two strings. They may be entered in either ASCII or hex format, but both strings must use the same format. Note that the ASCII is case sensitive.

The search begins at the current location of the cursor. If text is highlighted, the cursor is considered to be at the beginning of the highlight. The search is always down.

See also Replace, above.

Replace Next
Repeat the previous Find and Replace, starting just after the current location of the cursor or highlight.

Search Menu

Go to the beginning of the file. Note that this moves the cursor to the beginning of the file also, to make it easy to search again from the top.
Go To
Go to a specified location in the file. You will be prompted for the location (address). You can enter it in decimal or in hex. Simply select the button labeled Decimal or Hex.
Go To Highlight
Go to the current cursor or highlight location.
Search the file, starting at the current cursor or highlight location, for a specified string. You will be prompted to enter the string to search for. You may enter it in ASCII or hexadecimal, by clicking on the button labeled ASCII or Hex. Note that the ASCII is case sensitive.

You can search in either direction. At the prompting menu, select Up (towards the beginning of the file) or Down (towards the end).

Search Next
Repeat the previous search, but starting from the byte after the current cursor location.

View Menu

Font Sizes
Change the size of the display font or the printer font. Font sizes are in points, and the default is 12 points.
Refresh the display. This should not normally be necessary.
Hide or view the toolbar. The toolbar is the row of square icons just below the menu bar, at the top of the frame. Default is to view it.
Status Bar
Hide or view the status bar. When there are no child windows, this command refers to the status bar of the main frame, which displays information on any menu item or toolbar icon when the mouse is positioned over it.

When child windows are open, this command controls the status bar at the bottom of the active child window. This status bar displays the current location of the cursor or highlight within the file, the contents of the byte at that location, and the total file size in bytes (decimal and hex).

Window Menu

New Window
Open another subwindow on the currently active document. This allows you to look at a different location in the same file. Edits made in any subwindow affect all subwindows.
Arrange all subwindows in overlapping fashion.
Arrange all subwindows side by side. This may cause the ssubwindows to be resized to fit.
Arrange Icons
When child windows (subwindows) are minimized within the parent frame, this command arranges them at the bottom of the parent frame.
Default Size
Restore the active open child window to its default size, 16 rows high, and just wide enough to see the output.

Help Menu

Help Topics
Opens this window with these help pages.
Legal Notice
Brief disclaimer of warranty, and support address.
Version information

The Toolbar

The toolbar duplicates the more commonly used menu functions. For detailed descriptions, click on the links.

File menu
Edit menu
Find and Replace...
Search menu
Window menu
Help menu

Keyboard Shortcuts

There are keyboard shortcuts for some of the more commonly used menu functions. For detailed descriptions, click on the links.

File menu
Ctrl+N New
Ctrl+O Open...
Ctrl+S Save
Ctrl+P Print...
Edit menu
Ctrl+Z Undo
Ctrl+Y Redo
Ctrl+X Cut
Ctrl+C Copy
Ctrl+V Paste
Shift+Ctrl+F Find and Replace...
Shift+F3 ReplaceNext
Search menu
Ctrl+F Search...
F3 SearchNext
Help menu
F1 HelpTopics