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Reference for unit 'daemonapp' (#fcl)

Reference for unit 'daemonapp'

Daemon (service) application class

`uses`
`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.