Registry Use with Windows NT Clients
For many users, the Windows NT registry is a bit of a mystery, enough so that when users experience problems with their registry setup, often the only solution they are comfortable with is to completely reinstall the products. While this is usually the safest solution, it is often not the solution of choice.
The NT registry is divided into a series of hives, which is the term for the tree structure in which the data is organized. The registry is actually kept in two hidden flat files in the operating system directory. Each Windows system that supports the registry uses a differently named program to view and edit the registry:
Windows 3.51: Use regedt32
Windows 4.0: Use either regedt32 or regedit
Windows 95: Use regedit
As an example, we'll look at the listing of root-level hives on a Windows 95 system using regedit:
Informix Windows client and server products use two of the six main registry hives:
\HKEY_CURRENT_USERSoftwareInformix: Holds user-level profile information.
\HKEY_LOCAL_MACHINESoftwareInformix: Holds Informix global information for all users.
Each of the registry editing programs gives you the option of saving either the entire registry or parts of it to a file. By default these files end in the suffix *.reg. It is a good idea on all Windows 95 and Windows NT systems to occasionally take a copy of the registry files and keep this copy with your backups. Also, be sure that your backup program is capable of and actually does take a copy of the registry with backups. If the registry becomes corrupted, your entire system may be unusable.
For those who do many client installs, sometimes it is handy to place the install files on the network and do the install over the network. This can be done in one of two ways. Either place the "raw" install disk data on a hard disk and run the setup program for each install, or copy from an existing, running system. Using the install program is the recommended solution from Informix, but that entails a lot of duplicate work and is very difficult or impossible to totally automate via a script.
On the other hand, just taking a copy of the %INFORMIXDIR directory will not save the registry data, and your new system will not be usable without the registry information. Fortunately, it is possible to use the regedit program to get around this. First, on an installed and correctly operating machine, save off a copy of the SoftwareInformix subtrees on the two hives, \HKEY_CURRENTUSER and \HKEYLOCALMACHINE. Save each hive with a unique name. Then copy the entire directory tree of the Informix products you want to copy to the new machine, being sure that the directory tree and disk naming conventions are the same. Then go into regedit and load the copies of each of the two hives you saved. Finally, allow the new user to go into setnet32 and supply her own passwords. This a simple solution that can easily be incorporated into a script.
As an educational exercise, the user can go into the regedit program and browse through the hives and subhives in order to see exactly what Informix is doing with your registry. As long as you do not make any modifications to the registry, this is a safe procedure and can give you a much better understanding of what is happening under the covers.
Another source of registry information is in the help file for the setnet32 program. As a general rule, the help files of all of the Informix products for Windows contains a lot of good, useful information. The screen shot on the next page comes from the setnet32 help file system. Go through the help files and explore all of the little nooks and crannies. Click on all of the hyperlinks. Who knows what you'll find?
