Windows service
A Windows service is a program that runs as a specialized service in the background of Windows and functionality of the operating system bundles to make them available to third parties. Conceptually, it is similar to the Unix daemon.
Operation
Windows system services (even just a service or English Services) so to speak, form the "backbone " of Windows and convey it often between the hardware level and the software level. A good example of this is the "Plug & Play" service without these could use the attached hardware ( eg, a mouse ) neither applications nor a device could automatically log on to the operating system. Through a so-called service contract (also interface specification ) know both hardware and software in advance exactly how they need to address a service to use a specific functionality.
The actual implementation of the service depends on the environment (Windows Version, 32 or 64bit system, etc), the interfaces of the "Plug & Play" service but are on all Windows operating systems ( XP), in principle, almost identical or at least backward compatible.
Services do not communicate this directly with the user, they themselves have no user interface. Often there is to configure and control a service separate programs in Windows most of these programs are summarized in the Control Panel.
Windows provides the service control manager services.exe ready manages the starting and stopping services. He is a RPC server. Its user interface are the Microsoft Management Console and the command-line interpreter cmd.exe. A program that is to be started as a service, must be written so that it with the commands start | stop can bypass the Service Control Manager | pause | continue.
As a rule, to be executed before service programs as an executable file. In a Dynamic Link Library present programs (service host) are the executable file Svchost.exe called, which loads the services running and terminated, as appropriate. A service can be started automatically at startup of the operating system to be started manually at the request of other programs or be disabled.
A service is installed by its name, the executable file and other information will be entered into the registry database. Working standard services as Local System has Full Control permission. But they can also be set up so that they work under a user account or with minimal access rights as Network Service or Local Service.
Management
Services can be managed using the MMC snap-in Services.msc. Advanced options, such as creating, deleting and defining the interdependencies of services, the command line tool sc.exe. This is included in the default installation of Windows since Windows XP or Windows Server 2003, but can also be installed on other Windows versions on the Resource Kit.
Applications
Some basic system functions provided by any Services. Such services will be started regardless of the version of Windows automatically with the operating system.
Examples:
Even programs that are not included with Windows, working regularly as a service. Typical examples thereof are:
- Server of any kind
- Antivirus programs and other security software
- Tools for data backup and replication