Are pointers to variables and functions possible?

[martin]

I know that you can use DllStructCreate to store a variable at an address, or use DllStructGetPtr to find the address, but can the address of a variable be found, and can pointers be used in any way in AutoIt apart from using DllStructs?

Like in C for example,

Int *pVar

.

.

pvar = &Var3

.

.

. *pVar = 9

Is any equivalent possible in AutoIt?

AdLibEnable and GuiRegisterMsg are examples of functions in AutoIt which appears to point to the function to run, so how could that be done otherwise?

For example, if you created a timer with the SetTimer API, then it is possible to pass it the address of a function to run, but how could I do that?

[martin]

perhaps...

http://www.autoitscript.com/forum/index.ph...st&p=384128

Thanks Larry. I hadn't looked at that before, and now that I have my head hurts!

As I understand what I just looked at, Piccaso creates a piece of code in memory which calls the functions you want to use, and gives the address of where that piece of code is so that you can pass that address to the function for the routine to call.

I'll have a play with it.

But it doesn't help with using pointers and addresses for variables etc does it ?

[Zedna]

DllStructCreate and DllStructGetPtr:

$struct = DllStructCreate("int;char")
DllStructSetData($struct, 1, 467)
DllStructSetData($struct, 2, "abcdef")

$pointer1 = DllStructGetPtr($struct, 1); pointer to integer variable
$pointer2 = DllStructGetPtr($struct, 2); pointer to string variable

Edited September 3, 2007 by Zedna

[martin]

what do you need for pointer to variable?

I don't but I'm interested to see how to share data between programs. If you set up an area of memory it would be easier to use pointers and addresses so that when a variable changes it could be written directly to the shared memory.

and timer is like...

#include "DllCallBack.au3"

$hwin = WinGetHandle(AutoItWinGetTitle())

$hStub_Timer = _DllCallBack ("TimerProc", _ ; Name of the function
                                   "hwnd;int;ptr;int")           

$h = DllCall("user32.dll", "int", "SetTimer", "hwnd", $hwin, "int", 0, "int", 5000, "ptr", $hStub_Timer)

While 1
    Sleep(20)
WEnd

Func OnAutoItExit()
    DllCall("user32.dll","int","KillTimer","hwnd",$hwin,"int",$h[0])
EndFunc

Func TimerProc($hwnd,$uMsg,$idEvent,$dwTime)
    ToolTip($hwnd&@LF&$uMsg&@LF&$idEvent&@LF&$dwTime)
EndFunc

Now he tells me! Thanks Larry, I just spent over an hour working out how to use callbacks for some timers. The only thing I did which you didn't in your example is give the timers ID numbers so that when one times out you know which one it is. I posted it here.