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

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 […]

Written By
CodeGuru Staff
CodeGuru Staff
May 17, 1999
2 minute read
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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.



IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED
TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY REDISTRIBUTE
THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR
INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA
BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A
FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER
OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

Download tool – 20 KB

Date Last Updated: May 17, 1999

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