Applications can help get you out of life in DLL hell (InfoWorld)

February 16, 1998
Applications can help get you out of life in DLL hell
Readers proposed in my column last week a variety of solutions for DLL hell. This happens when your system becomes buggy because an application installs an older DLL over a newer one. Sometimes even installing a newer DLL over an older one makes applications go crazy.
This week, I'd like to report on some solutions that developers have created to extinguish DLL hell.
DLL Explorer is a diagnostic tool developed by Real Solutions, in Hawksburn, Australia. The tool is designed for Windows 95 and Windows NT 4.0. The program enables you to examine the current state of executables such as .EXE, .DLL, and .OCX files. You can compare the state of your system before and after loading and using a particular program.
DLL Explorer allows you to see what files are in use by which applications. Detecting that two programs are trying to load two different versions of a DLL can be the first step in isolating and solving a major headache. The registered version costs $20. For more information, see http://www.realsol.com.au and click on Products.
A more ambitious program, which is designed to provide customized cures, is called DLLaGator. This tool enables different applications to load and run different DLL versions with the same name -- something that is not usually possible under Windows.
The program works with Windows 95, Windows NT, and Windows 3.1, and it is produced by Chicago-Soft, in Hanover, N.H.
DLLaGator includes an Agent and an Administrator. The Agent reports on every module that is used by a client PC, either locally or across a network. DLLaGator can then compare the usage of modules by different PCs. This can highlight why some systems work well and others do not.
The Administrator component allows you to create "rules." These can be used to establish which DLLs will be run by which programs to avoid conflicts.
As an example, Chicago-Soft cites a corporate developer who had several Visual Basic applications using a particular .OCX file. Changes were required to the .OCX file, but the administrator did not want to risk tampering with the apps that were working correctly with the old .OCX. DLLaGator provided a solution by loading the new .OCX with the new app while continuing to load the old .OCX with the old apps.
Chicago-Soft sells DLLaGator with a site license that varies in price. For more information, see the company's Web site at http://www.chicago-soft.com/dllagator/.
I hope we won't need tools like these very much longer. I expect Microsoft to work out a permanent solution to DLL hell soon.

Back to work, airline travelers
I said in my Jan. 26 column that the tray tables in a few international airliners were magnetized and had corrupted some travelers' laptop hard drives. I wish I had printed this item in the April Fool's issue, because it turns out it's an Internet hoax.
MIS Sciences, one of several sources I reviewed for that story, has pulled the alert from its Web site. The International Air Transport Association (http://www.iata.org) confirms that none of the tray tables in these particular airliners are magnetized.
So now you can go back to crunching numbers on long flights. I've contributed the story to the Urban Legends home page (http://www.urbanlegends.com) for posterity.

Brian Livingston is the co-author of several best-selling Windows books, including the most recent Windows 95 Secrets (IDG Books). Send comments to brian_livingston@infoworld.com. Unfortunately, he cannot answer individual questions.
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