enable_raising_events() [2/2]

process & xtd::diagnostics::process::enable_raising_events

(

bool

value

)

Sets whether the xtd::diagnostics::process::exited event should be raised when the process terminates.

Parameters

value

true if the xtd::diagnostics::process::exited event should be raised when the associated process is terminated (through either an exit or a call to xtd::diagnostics::process::kill()); otherwise, false. The default is false. Note that the xtd::diagnostics::process::exited event is raised even if the value of xtd::diagnostics::process::enable_raising_events is false when the process exits during or before the user performs a xtd::diagnostics::process::has_exited check.

Remarks

The xtd::diagnostics::process::enable_raising_events property suggests whether the component should be notified when the operating system has shut down a process. The xtd::diagnostics::process::enable_raising_events property is used in asynchronous processing to notify your application that a process has exited. To force your application to synchronously wait for an exit event (which interrupts processing of the application until the exit event has occurred), use the xtd::diagnostics::process::wait_for_exit method.

If the component's xtd::diagnostics::process::enable_raising_events value is true, or when xtd::diagnostics::process::enable_raising_events is false and a xtd::diagnostics::process::has_exited check is invoked by the component, the component can access the administrative information for the associated process, which remains stored by the operating system. Such information includes the xtd::diagnostics::process::exit_time and the xtd::diagnostics::process::exit_code.

After the associated process exits, the xtd::diagnostics::process::handle of the component no longer points to an existing process resource. Instead, it can only be used to access the operating system's information about the process resource. The operating system is aware that there are handles to exited processes that haven't been released by xtd::diagnostics::process components, so it keeps the xtd::diagnostics::process::exit_time and xtd::diagnostics::process::handle information in memory.

There's a cost associated with watching for a process to exit. If xtd::diagnostics::process::enable_raising_events is true, the xtd::diagnostics::process::exited event is raised when the associated process terminates. Your procedures for the xtd::diagnostics::process::exited event run at that time.

Sometimes, your application starts a process but doesn't require notification of its closure. For example, your application can start Notepad to allow the user to perform text editing but make no further use of the Notepad application. You can choose to avoid notification when the process exits because it's not relevant to the continued operation of your application. Setting xtd::diagnostics::process::enable_raising_events to false can save system resources.