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cisco ucs book.Handles hide the actual memory address from the API user, while also allowing the system to transparently, for programs, reorganize physical memory. A handle not only identifies a value, but also associates access rights with that value. Handle leaks are likely to occur if a handle is not freed after it is used.8.7 ServicesThis section discusses the topic of Windows services, which are long-running executable applications that run within their own Windows session. Windows services basically run in the background. A service can be made to start automatically with the computer, for example, some of the application services shown in Figure 8-7. The service must conform to the Service Control Manager's interface rules and protocols.Figure 8-7 Windows Service Control ManagerServices can be either suspended or restarted. Figure 8.7 shows some of the services that are shown as "Started" under the "Status" column. You can see if a service starts automatically with the system by looking at the "Startup Type" column. To view the services on a Microsoft Windows system, type services.msc in the Run window and press Enter, which will immediately bring up the Service Control Manager window shown in Figure 8.7.Services are ideal for running within a user security context and can be used to launch applications that are dedicated to a specific user.350 Chapter 8 Windows-based Analysisprocedures, and can also run for long periods of time without interfering with other users using the same computer. For example, to monitor whether storage space consumed exceeds a certain threshold, a programmer could create a Windows service application to monitor storage space and set it to automatically start at the same time as the system to continuously monitor the critical state. If the user chooses not to monitor their system, they can open the Service Control Manager and change the service's start type to manual, which means that the service must be started manually. Of course, the user can also stop the service. Services in the Service Control Manager can be started, stopped, or triggered by events. Since the service runs within the user's respective account, it can be run when the user is not logged on to the system, meaning that the storage space monitoring application can be configured to run automatically for a specific user or for any other user, including when the user is not logged on to the system. Windows administrators can use the Services management unit (Servicessnap-in).Sc.exe or Windows PowerShellto manage services. "The Service Management Unit is built into the Service Management Console and allows the administrator to perform the following actions by connecting to a local or remote computer.