Get active window with Autohotkey

How it works

Pack this .ahk script to .exe

WinGet, process, ProcessName, A
FileAppend, %process%, *
ExitApp

Run it

GetActiveProcess.exe | more

More feature

Get active window title

WinGetTitle, title, A
FileAppend, "%title%
ExitApp

Get full process list

WinGet, windows, list

Loop, %windows%
{
    id := windows%A_Index%
    WinGet, process, ProcessName, ahk_id %id%
    WinGetTitle, title, ahk_id %id%
    FileAppend, %process% %title%`n, *
}
ExitApp

Full script

Loop, %0%
{
    param := %A_Index%
    break
}

if (param=="activeprocess")
{
    WinGet, process, processName, A
    FileAppend, %process%, *
}

if (param=="activetitle")
{
    WinGetTitle, title, A
    FileAppend, %title%, *
}

if (param=="all")
{
    WinGet, windows, list
    Loop, %windows%
    {
        id := windows%A_Index%
        WinGet, process, ProcessName, ahk_id %id%
        WinGetTitle, title, ahk_id %id%
        FileAppend, %process%:%title%`n, *
    }
}

ExitApp 

Written on November 16, 2017