powershell code for cleaning up all processes and child processes launched as part of the script

job_object.ps1

if (-not [System.Management.Automation.PSTypeName]'JobObject'.Type) {
    Add-Type @"
using System;
using System.Runtime.InteropServices;

public class JobObject
{
    [DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
    public static extern IntPtr CreateJobObject(IntPtr lpJobAttributes, string lpName);

    [DllImport("kernel32.dll", SetLastError = true)]
    [return: MarshalAs(UnmanagedType.Bool)]
    public static extern bool AssignProcessToJobObject(IntPtr hJob, IntPtr hProcess);

    [DllImport("kernel32.dll", SetLastError = true)]
    [return: MarshalAs(UnmanagedType.Bool)]
    public static extern bool TerminateJobObject(IntPtr hJob, uint uExitCode);

    [DllImport("kernel32.dll", SetLastError = true)]
    [return: MarshalAs(UnmanagedType.Bool)]
    public static extern bool CloseHandle(IntPtr hObject);
}
"@
}

# Create a Job Object
$jobHandle = [JobObject]::CreateJobObject([IntPtr]::Zero, "TestJobObject")
if ($jobHandle -eq [IntPtr]::Zero) {
    throw "Failed to create Job Object: $([System.ComponentModel.Win32Exception]::new([Runtime.InteropServices.Marshal]::GetLastWin32Error()).Message)"
}

try {
    # Start the child process (launch some processes from this, i.e. msinfo32 etc and then ctrl-c this script)
    $childProcess = Start-Process -FilePath "cmd.exe" -PassThru

    # Assign the process to the job object
    $processHandle = (Get-Process -Id $childProcess.Id).Handle
    if (-not [JobObject]::AssignProcessToJobObject($jobHandle, $processHandle)) {
        throw "Failed to assign process to Job Object: $([System.ComponentModel.Win32Exception]::new([Runtime.InteropServices.Marshal]::GetLastWin32Error()).Message)"
    }

    # Wait for either Ctrl-C or the process to exit
    while (!$childProcess.HasExited) {
        Start-Sleep -Milliseconds 500
    }
} finally {
    # Clean up - explicitly terminate all processes in the job
    Write-Host "Terminating job object and exiting."
    if (-not [JobObject]::TerminateJobObject($jobHandle, 0)) {
        Write-Host "Failed to terminate Job Object: $([System.ComponentModel.Win32Exception]::new([Runtime.InteropServices.Marshal]::GetLastWin32Error()).Message)"
    }
    if (-not [JobObject]::CloseHandle($jobHandle)) {
        Write-Host "Failed to close Job Object handle: $([System.ComponentModel.Win32Exception]::new([Runtime.InteropServices.Marshal]::GetLastWin32Error()).Message)"
    }
    exit 1
}