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Reference for unit 'DaemonApp'

Daemon (service) application class.

uses

Used units Description
System
CustApp Custom application class.
Classes
sysutils
EventLog Unit implementing system log class.
rtlconsts Constant strings for messages.

Overview

The daemonapp unit implements a TApplication class which encapsulates a daemon or service application. It handles installation where this is necessary, and does instantiation of the various daemons where necessary.

The unit consists of 3 separate classes which cooperate tightly:

TDaemon
This is a class that implements the daemon's functionality. One or more descendents of this class can be implemented and instantiated in a single daemon application. For more information, see TDaemon.
TDaemonApplication
This is the actual daemon application class. A global instance of this class is instantiated. It handles the command-line arguments, and instantiates the various daemons. For more information, see TDaemonApplication.
TDaemonDef
This class defines the daemon in the operation system. The TDaemonApplication class has a collection of TDaemonDef instances, which it uses to start the various daemons. For more information, see TDaemonDef.

As can be seen, a single application can implement one ore more daemons (services). Each daemon will be run in a separate thread which is controlled by the application class.

The classes take care of logging through the TEventLog class.

Many options are needed only to make the application behave as a windows service application on windows. These options are ignored in UNIX-like environment. The documentation will mention this.