? bug in DLL function?

[randallc]

Hi,

I had to make a workaround to get the APIWrite to work in Larry's function, but he is not replying to queries; ? a bug in the DLL functions? [DllStructCreate] etc

See.

1. Working example and links to other example zip.

TailRW.au3 UDF Demo

2. detail below of workaround (if "+1") NOT added within the DLL "char[" creation, then written strng shortened by 1 and "chr(0)" added at end!

Best, Randall

Func _APIFileWrite($hFile, $szData, $Option = 0)
    ;##############################
    ; _APIFileWrite( <FileHandle>, <Data to Write>, [ <Option 0=String | 1=Binary(hex)> ] )
    ;
    ; For binary <Data to Write> must be comma delimited hex values.
    ;
    ; Return - # of Bytes written
    ;          sets @error to the return from WriteFile api
    ;##############################
;~  $timerw = TimerInit()
    Local $AFW_r, $AFW_n, $AFW_i, $AFW_ptr
    If $Option = 0 Then
        $AFW_n = StringLen($szData)
        $AFW_ptr = DllStructCreate("char[" & $AFW_n + 1 & "]");+1; workaround fix
        DllStructSetData($AFW_ptr, 1, String($szData))
    Else
        $szData = StringSplit($szData, ",")
        $AFW_n = $szData[0]
        $AFW_ptr = DllStructCreate("byte[" & $AFW_n & "]")
        For $AFW_i = 1 To $AFW_n
            DllStructSetData($AFW_ptr, 1, Dec($szData[$AFW_i]), $AFW_i)
        Next
    EndIf
    $AFW_r = DllCall("kernel32.dll", "int", "WriteFile", "hwnd", $hFile, "ptr", DllStructGetPtr($AFW_ptr), "long", $AFW_n, "long_ptr", 0, "ptr", 0)
    SetError($AFW_r[0])
    $AFR_ptr = "";DllStructDelete($AFR_ptr)
;~  ConsoleWrite("_APIFileWrite time=" & TimerDiff($timerw) & @LF)
    Return $AFW_r[4]
EndFunc   ;==>_APIFileWrite

Edited August 23, 2006 by randallc

[jpm]

I understand you find a bug in a non distributed API so I move the thread to support hopping Larry will answer

[randallc]

Hi,

I thought it was a bug in AutoIt "DllStructCreate" function; what do you mean by "non-distributed"?

Am I wrong about that?

Best, Randall

[PS or DllStructSetData, DllCall, DllStructGetPtr?]

Edited August 27, 2006 by randallc

[jpm]

Hi,

I thought it was a bug in AutoIt "DllStructCreate" function; what do you mean by "non-distributed"?

Am I wrong about that?

Best, Randall

[PS or DllStructSetData, DllCall, DllStructGetPtr?]

for me it is specific to your use of the _APIFileWrite

as stringlen is not returning the ending chr(0) needed for a string in your case.

I think Larry will confirm

[randallc]

OK, thanks; I see the structure was calling back one too few characters for the string.

It was not "my" use of the "APIwrite", though; it was a pre-written UDF which I have only changed as a workaround as it was not working accurately [deliberately perhaps???].

Thanks again for the explanation.

Best, Randall

Edited August 28, 2006 by randallc