Windows Native Toolkit | Process Window Library

Use this library for trusted launcher workflows, external tools, process control, and packaged-game window management.

Python examples use Unreal's reflected API names through the unreal module. Use the packaged-runtime safeguards described below before calling relaunch or force-kill helpers from Python.

Include The Modules

This page covers nodes from two plugin modules.

Source/MyProject/MyProject.Build.cs

PublicDependencyModuleNames.AddRange(
	new string[]
	{
		"Core",
		"CoreUObject",
		"Engine",
		"SystemUtilityModule",
		"DeviceFrameworkModule"
	}
);

Source/MyProject/MyClass.cpp

#include "OpenApps.h"
#include "HardwareInfoLibrary.h"

Launch App

Launches an external executable and returns the best process ID found for it.

Pin	Direction	Description
`ExePath`	Input	Executable file path to launch.
`Arguments`	Input	Command-line arguments appended after the executable path.
`bHidden`	Input	Hides the launched process window when Windows allows it.
`Return Value`	Output	Best process ID found for the launched process tree.

C++ Example

#include "OpenApps.h"

const int32 ProcessId = UOpenApps::LaunchExternalProcess(
	TEXT("C:/Tools/MyApp.exe"),
	TEXT("--minimized"),
	true
);

Python Example

import unreal

process_id = unreal.OpenApps.launch_external_process(
    "C:/Tools/MyApp.exe",
    "--minimized",
    True,
)

Kill Process Tree

Terminates a process and its discovered child processes.

Pin	Direction	Description
`ProcessID`	Input	Root process ID to terminate.
`Return Value`	Output	True when the root process is no longer running after the kill attempt.

C++ Example

#include "OpenApps.h"

const bool bKilled = UOpenApps::KillProcessTree(ProcessID);

Python Example

import unreal

killed = unreal.OpenApps.kill_process_tree(process_id)

Is Process Running

Checks whether a process ID is still active.

Pin	Direction	Description
`ProcessID`	Input	Process ID to check.
`Return Value`	Output	True when the process is still running.

C++ Example

#include "OpenApps.h"

const bool bRunning = UOpenApps::IsProcessRunning(ProcessID);

Python Example

import unreal

is_running = unreal.OpenApps.is_process_running(process_id)

Focus App

Brings the main visible window for a process to the foreground.

Pin	Direction	Description
`ProcessID`	Input	Process ID whose visible top-level window should be focused.
`Return Value`	Output	True when a matching window was found and activated.

C++ Example

#include "OpenApps.h"

const bool bFocused = UOpenApps::BringAppToFront(ProcessID);

Python Example

import unreal

focused = unreal.OpenApps.bring_app_to_front(process_id)

Can Relaunch Game

Returns whether the current runtime context safely allows relaunching the packaged game executable.

Pin	Direction	Description
`Return Value`	Output	True when the runtime is not editor or commandlet and the executable path is usable.

C++ Example

#include "HardwareInfoLibrary.h"

const bool bCanRestart = USystemInfoBPLibrary::CanRestartGame();

Python Example

import unreal

can_restart = unreal.SystemInfoBPLibrary.can_restart_game()

Relaunch Game

Relaunches the packaged game executable with optional extra command-line text.

Pin	Direction	Description
`ExtraCommandLine`	Input	Extra command-line text appended to the relaunched process.

C++ Example

#include "HardwareInfoLibrary.h"

USystemInfoBPLibrary::RestartGameWithCommandLine(TEXT("-myflag=value"));

Python Example

import unreal

unreal.SystemInfoBPLibrary.restart_game_with_command_line("-myflag=value")

Can Force Kill Game

Returns whether a hard process kill is allowed in the current runtime context.

Pin	Direction	Description
`Return Value`	Output	True when the plugin allows immediate process termination.

C++ Example

#include "HardwareInfoLibrary.h"

const bool bCanKill = USystemInfoBPLibrary::CanForceKillGame();

Python Example

import unreal

can_force_kill = unreal.SystemInfoBPLibrary.can_force_kill_game()

Force Kill Game Process

Immediately terminates the packaged game process.

Pin	Direction	Description
No pins	Output	The current process is terminated when the runtime allows it.

C++ Example

#include "HardwareInfoLibrary.h"

USystemInfoBPLibrary::ForceKillGame();

Python Example

import unreal

unreal.SystemInfoBPLibrary.force_kill_game()

Process Window Library

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