KeyCHW: A Compression Utility for MSDN (and other large help systems)

A .CHW file is just a .CHM file with a different extension. By default, a .CHW file isn't compressed since compression can require a fair amount of memory, and not all machines will be able to handle the memory requirements. But if you ship a CHW file with your product, or you have large CHW files on your machine (e.g., MSDN), then KeyCHW can significantly reduce the size of the CHW file. Compression is in the neighborhood of 85%. With large CHW files like MSDN, this can save over 30 megabytes of hard disk space.

KeyCHW is a DOS Console program. When you download it, you should save it to your windows folder, or some folder within your PATH environment. To run it, you need to start up a DOS box, switch to the folder containing the CHW file or files you want to compress and type "KeyCHW" followed by the names of the CHW files to compress. If you want to compress all the CHW files in that folder, simply type "KeyCHW *.chw".

Compression can take a long time, so don't be surprised if you don't see any activity for quite awhile. For example, to compress the 35 megabyte CHW file that ships with Visual Studio 6, it will take around 2 and a half minutes on a P450 (but you will end up with a file 1/10th the size!).

KeyCHW is free -- you can install it wherever you want, give it to whoever you want, etc. Of course, we do have the legal disclaimer stuff to take care of:

BECAUSE THIS PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THIS PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM ``AS IS'' WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.

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