AutoHotkey Community

;Sender-Script
RecPID := 1596 ;change this according to the MsgBox in the Receiver-Script
Message := 1111
return
^L::
Message += 1
result := Send_WM_COPYDATA(Message, RecPID)
MsgBox, %result%     
return

Send_WM_COPYDATA(ByRef Message, ByRef RecPID)
{
    VarSetCapacity(CopyDataStruct, 12, 0)
    NumPut(StrLen(Message) + 1, CopyDataStruct, 4)
    NumPut(&Message, CopyDataStruct, 8)
    Prev_DetectHiddenWindows := A_DetectHiddenWindows
    Prev_TitleMatchMode := A_TitleMatchMode
    DetectHiddenWindows On
    SetTitleMatchMode 2
    SendMessage, 0x4a, 0, &CopyDataStruct,, ahk_PID%RecPID%
    DetectHiddenWindows %Prev_DetectHiddenWindows%
    SetTitleMatchMode %Prev_TitleMatchMode%
    return ErrorLevel  ;
}

;Receiver-Script
PID := DllCall("GetCurrentProcessId")
OnMessage(0x4a, "Receive_WM_COPYDATA")
MsgBox, RecPID := %PID%
Tooltip, Waiting
return

Receive_WM_COPYDATA(wParam, lParam)
{
   global BCCCopyOfData
    lpDataAddress := lParam + 8
    lpData := 0
    Loop 4
    {
        lpData := lpData | (*lpDataAddress << 8 * (A_Index - 1))
        lpDataAddress += 1
    }
    DataLength := DllCall("lstrlen", UInt, lpData)
    if DataLength <= 0
        ToolTip %A_ScriptName%`nA blank string was received or there was an error.
    else
    {
        VarSetCapacity(CopyOfData, DataLength)
        DllCall("lstrcpy", "str", CopyOfData, "uint", lpData)
        BCCCopyOfData := CopyOfData
        SetTimer, DoTooltip, -1000
    }
    return true
}

DoTooltip:
   ToolTip %A_ScriptName%`nReceived the following string:`n%BCCCopyOfData%
; sleep, 1000
; Tooltip
return

SendMessage, 0x4a, 0, &CopyDataStruct,, ahk_PID %RecPID% ahk_class AutoHotkey

;Receiver-Script
Receiver=
(
OnMessage(0x4a, "Receive_WM_COPYDATA")
Tooltip, Waiting
return

Receive_WM_COPYDATA(wParam, lParam)
{
   global BCCCopyOfData
    lpDataAddress := lParam + 8
    lpData := 0
    Loop 4
    {
        lpData := lpData | (*lpDataAddress << 8 * (A_Index - 1))
        lpDataAddress += 1
    }
    DataLength := DllCall("lstrlen", UInt, lpData)
    if DataLength <= 0
        ToolTip `%A_ScriptName`%``nA blank string was received or there was an error.
    else
    {
        VarSetCapacity(CopyOfData, DataLength)
        DllCall("lstrcpy", "str", CopyOfData, "uint", lpData)
        BCCCopyOfData := CopyOfData
        SetTimer, DoTooltip, -1000
    }
    return true
}

DoTooltip:
   ToolTip `%A_ScriptName`%``nReceived the following string:``n`%BCCCopyOfData`%
return
)



PID:=RunTempScript(Receiver,"Receiver")


;Sender-Script
Sender=
(
RecPID = %PID%
Message := 1111
Gosub, ^L
return
^L::
Message += 1
result := Send_WM_COPYDATA(Message, RecPID)
MsgBox, `%result`%     
return

Send_WM_COPYDATA(ByRef Message, ByRef RecPID)
{
    VarSetCapacity(CopyDataStruct, 12, 0)
    NumPut(StrLen(Message) + 1, CopyDataStruct, 4)
    NumPut(&Message, CopyDataStruct, 8)
    Prev_DetectHiddenWindows := A_DetectHiddenWindows
    Prev_TitleMatchMode := A_TitleMatchMode
    DetectHiddenWindows On
    SetTitleMatchMode 2
    SendMessage, 0x4a, 0, &CopyDataStruct,, ahk_PID `%RecPID`% ahk_class AutoHotkey
    DetectHiddenWindows `%Prev_DetectHiddenWindows`%
    SetTitleMatchMode `%Prev_TitleMatchMode`%
    return ErrorLevel  ;
}
Return
)

RunTempScript(Sender,"Sender")

ExitApp


RunTempScript(TempScript, name="")
{
   global #__AHK_EXE_
   If Name =
      #__PIPE_NAME_ := A_TickCount
   Else
      #__PIPE_NAME_ := name
   #__PIPE_GA_ := CreateNamedPipe(#__PIPE_NAME_, 2)
   #__PIPE_    := CreateNamedPipe(#__PIPE_NAME_, 2)
   if (#__PIPE_=-1 or #__PIPE_GA_=-1) {
      MsgBox CreateNamedPipe failed.
      Return
   }
   Run, %A_AhkPath% "\\.\pipe\%#__PIPE_NAME_%",,UseErrorLevel HIDE, PID
   If ErrorLevel
      MsgBox, 262144, ERROR,% "Could not open file:`n" #__AHK_EXE_ """\\.\pipe\" #__PIPE_NAME_ """"
   DllCall("ConnectNamedPipe","uint",#__PIPE_GA_,"uint",0)
   DllCall("CloseHandle","uint",#__PIPE_GA_)
   DllCall("ConnectNamedPipe","uint",#__PIPE_,"uint",0)
   script := chr(239) . chr(187) . chr(191) . TempScript
   if !DllCall("WriteFile","uint",#__PIPE_,"str",script,"uint",StrLen(script)+1,"uint*",0,"uint",0)
      MsgBox WriteFile failed: %ErrorLevel%/%A_LastError%
   DllCall("CloseHandle","uint",#__PIPE_)
   Return PID
}

CreateNamedPipe(Name, OpenMode=3, PipeMode=0, MaxInstances=255) {
   return DllCall("CreateNamedPipe","str","\\.\pipe\" Name,"uint",OpenMode
      ,"uint",PipeMode,"uint",MaxInstances,"uint",0,"uint",0,"uint",0,"uint",0)
}

SendMessage, 0x4a, 1, &CopyDataStruct,, ahk_PID %param1% ahk_class AutoHotKey