I am not able to obtain the address of a variable

[Zomp]

I thought that ptr() is the function to obtain the address of a variable.

But in the following toy script:

$T1="00"

for $i=1 to 15
   $T1&=$T1
Next

msgbox(0,"length $T1",stringlen($T1))

$T2=$T1

$AddressT1=ptr($T1)
msgbox(0,"AddressT1",$AddressT1)
$AddressT2=ptr($T2)
msgbox(0,"AddressT2",$AddressT2)

I see that both $AddressT1 and $AddressT2 are 0x00000000.

So, what is my mistake?

Thanks for your patience.

[TerarinKerowyn]

Ptr() can only decipher decimal number so any 0-9 are correct. However your can only count up to 4294967295 but you got to the power of 15 start with 00 so 00^15. Remember that 0 does mean something regardless to where it is so you end up with countless 00. Appro. 00 x 120000 as a rough estimate with great margin of error. However it does evaluate as long as T1 or T2 are under 4294967295

Here is a estimate that you were looking for:

$T1="42949"

$T2=$T1

$T1 &= $T1

msgbox(0,"length $T1",$T1 & " " & stringlen($T1))

$AddressT1=ptr($T1)

If IsPtr($AddressT1) Then

msgbox(0,"AddressT1",$AddressT1)

EndIf

$AddressT2=ptr($T2)

If IsPtr($AddressT2) Then

msgbox(0,"AddressT2",$AddressT2)

EndIf

You are workign with a 32 bit system if you want higher up you need to go to 64 bit system else enumate two different as a Pointer

[Zomp]

Ptr() can only decipher decimal number so any 0-9 are correct. However your can only count up to 4294967295 but you got to the power of 15 start with 00 so 00^15. Remember that 0 does mean something regardless to where it is so you end up with countless 00. Appro. 00 x 120000 as a rough estimate with great margin of error. However it does evaluate as long as T1 or T2 are under 4294967295

Sorry, I am not sure to have well understood. If Ptr() only converts a number, then I have used the wrong function. The content of $T1 and $T2 is not important. They can be "AAAAAAAAAAAA" and "AAAAAAAAAAAAA".

I have a string variable whose length is 65536. Now I have to pass its address as a parameter in a dll call. How have I to do?

Edited April 13, 2008 by Zomp

[Zomp]

I have a string variable whose length is 65536. Now I have to pass its address as a parameter in a dll call. How have I to do?

I have found the solution by myself. I have to use DllStruct* functions.

Here is a toy example:

$a=DllStructCreate("char FNI[10000]")

if @error Then
    MsgBox(0,"","Error in DllStructCreate " & @error);
    exit
endif

$T1="00"
for $i=1 to 15
   $T1&=$T1
Next

DllStructSetData($a,1,$T1)

if @error Then
    MsgBox(0,"","Error in DllStructSetData " & @error);
    exit
endif

MsgBox(0,"DllStruct","Struct Size: " & DllStructGetSize($a) & @CRLF & _
        "Struct pointer: " & DllStructGetPtr($a) & @CRLF & _
        "Data:" & @CRLF & DllStructGetData($a,1))

I'm wondering if I can avoid to use DllStruct* and use for example "&" before the variable name as in AutoHotKey.

Edited April 13, 2008 by Zomp

[martin]

I have found the solution by myself. I have to use DllStruct* functions.

Here is a toy example:

$a=DllStructCreate("char FNI[10000]")

if @error Then
    MsgBox(0,"","Error in DllStructCreate " & @error);
    exit
endif

$T1="00"
for $i=1 to 15
   $T1&=$T1
Next

DllStructSetData($a,1,$T1)

if @error Then
    MsgBox(0,"","Error in DllStructSetData " & @error);
    exit
endif

MsgBox(0,"DllStruct","Struct Size: " & DllStructGetSize($a) & @CRLF & _
        "Struct pointer: " & DllStructGetPtr($a) & @CRLF & _
        "Data:" & @CRLF & DllStructGetData($a,1))

I'm wondering if I can avoid to use DllStruct* and use for example "&" before the variable name as in AutoHotKey.

Unfortunately you cannot get the address of variables in AutoIt, only for DllStructs.

I though that I could beat the system because when you call a dll with a string parameter the string must be passed as a pointer. So I wrote a dll with a function to be called with a string from AUtoIt, then tried to use the value passed for the string in a memory read. I couldn't get it to work . Probably something wrong with my understanding.