VDF GUI dance

This code is part of «VDF GUIdance»
Visit us @ http://www.vdf-guidance.com
e-Mail us @ info@vdf-guidance.com
VDF GUIdance is a mutual project of
Frank Vandervelpen - Vandervelpen Systems and
Wil van Antwerpen - Antwise Solutions

Software running as a service on NT

Author: Frank G. Vandervelpen (Original published as a web White paper)

Ownership: Mutual project of Vandervelpen Systems and Antwise solutions

DataFlex-version: 4.0/5.0/6.0 (VDF)

Purpose

This document describes the way to migrate a software (i.e. a VDF program) towards a service on Microsoft Windows NT4.0 ®. There are a lot of reasons why this could be done. Suppose we want software of us running continuously, even when someone is not logged in. This can be for security sake. A second argument to do this is because people want to make backups. Sometimes, it is hard to make backups when a software is running and it might be locking databases and blocking other things. Whenever you have a good backup, or when you have a script for running automatic backups, you can unload and reload a service from within this kind of environment. We have had a special request of one of our customers to implement this as I describe it here. At this stage, we do not exactly know how VDF is reacting on a service, but we’ll find out really soon.

Responsibility

This document can be used as a feedback document, but you have to double-check everything. We are not responsible for direct or indirect faults or loss to hardware, software or data on your information system.

Requirements

We have done our project on a Windows NT 4.0 ® Int’l Edition Server with Support Pack 3. In addition we have installed the Microsoft Windows NT 4.0 ® Resource kit.

Services do…

Allow applications to survive logon/logoff sequences, hence saving the overhead of restarting them for each user whom logs on…

Allow server applications to come-up and service requests even when no user is logged on.

Increases security of your server, cause it can handle requests from booting position. Interesting to use in combination with UPS.

Allows applications to run and perform a task in a specific account, differently from the current logged into the system and let it apply the rights to that user.

Note

As far as I could understand you can not run a user-data entry and network aware software in one service. You have to make a choice between those.

Steps to Follow

«Start-Run» SRVINSTW (Carriage Return)
Option Install a Service
Option Local Machine
Give the Service a Name: i.e. vsService
Please enter the full path for the executable: d:\projectname\programs\dfrun.exe
Now you select the option: Service its own Process
The next step lets you define the rights that are necessary to run the software: in your case, the VDF program
i.e. System Account and we check the option: Allow service to interact with desktop. You can also supply a specific account and his password… You and/or the local system administrator are the best-qualified person to take this decision.
The next step will determine the «startup» option for the service. The most interesting is the «Automatic» option.
The service will now finish the installation of the service.
This task has made a certain registry key that you can eventually modify. Start the «Registry» editing software. Browse towards the following key: HKEY_LOCAL_MACHINE+SYSTEM+CURRENTCONTROLSET+SERVICES and look for the service name that you have defined (i.e. vsService)
Now, you have to make some manual changes to the keys. You always have to define pathnames and stuff like that as a pointer towards local drives. We can not use any UNC coding in this stage.
Under the above registry key, you have to change the entry of the key ImagePath towards something like "C:\ntResKit\srvany.exe"
If you want the service to load automatic the key, Start should be 0x00000002
Make a new sub-key under the above key. Call this one Parameters
Under this, make a key (String Value) called Application and place directory and executable name in it. (i.e. C:\vdf\dfrun.exe"
Under this, make a key (String Value) called AppParameters and place the optional parameters in it. (i.e. MyProject BTW this could be the key of your VDF project, or the location of your VDF-program)
Under this, make a key (String Value) called AppDirectory and place the working directory in this one. Very important to find things back.
The software is now defined as a service!
Please check whether your Service Account User (Control Panel – Services – YourService) is used by the account that has the proper rights (i.e. MyDomain\Administrator) This is often a crucial element whether your service will run or not.

The next part will show you an example of the registry settings for such a service definition of a program.

REGEDIT4

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WANExchange]
"Type"=dword:00000110
"Start"=dword:00000002
"ErrorControl"=dword:00000001
"DisplayName"="WANExchange"
"ObjectName"="LocalSystem"
"ImagePath"=hex(2):63,3a,5c,6e,74,52,65,73,6b,69,74,5c,73,72,76,61,6e,79,2e,65,\
78,65,00

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WANExchange\Parameters]
"AppParameters"="WANexchange.vdf"
"AppDirectory"="H:\\accoflex\\mits\\wan\\programs\\"
"Application"="H:\\accoflex\\Mits\\Wan\\Programs\\Dfrun.exe"

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WANExchange\Security]
"Security"=hex:01,00,14,80,c0,00,00,00,cc,00,00,00,14,00,00,00,34,00,00,00,02,\
00,20,00,01,00,00,00,02,80,18,00,ff,01,0f,00,01,01,00,00,00,00,00,01,00,00,\
00,00,20,02,00,00,02,00,8c,00,05,00,00,00,00,00,18,00,8d,01,02,00,01,01,00,\
00,00,00,00,01,00,00,00,00,f8,00,14,00,00,00,1c,00,fd,01,02,00,01,02,00,00,\
00,00,00,05,20,00,00,00,23,02,00,00,06,00,00,00,00,00,1c,00,ff,01,0f,00,01,\
02,00,00,00,00,00,05,20,00,00,00,20,02,00,00,06,00,00,00,00,00,1c,00,ff,01,\
0f,00,01,02,00,00,00,00,00,05,20,00,00,00,25,02,00,00,06,00,00,00,00,00,18,\
00,fd,01,02,00,01,01,00,00,00,00,00,05,12,00,00,00,25,02,00,00,01,01,00,00,\
00,00,00,05,12,00,00,00,01,01,00,00,00,00,00,05,12,00,00,00

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WANExchange\Enum]
"0"="Root\\LEGACY_WANEXCHANGE\\0000"
"Count"=dword:00000001
"NextInstance"=dword:00000001