how to determine is a file is open by another program

[Dana]

This one has me stumped.

I'm working on a routine that, among other things, exports a .pdf file from KeyCreator (a CAD package). I can do that part no problem, but I've been unable to determine when the pdf export process is done.

I use Send to start the pdf export, WinWaitActive to wait for the "Save As" dialog, stuff the desired filename into the dialog, click OK, etc., but then I need to wait until the export is complete before continuing. Unfortunately, once the "save as" dialog closes, there is nothing in the main KeyCreator window that's visible to indicate that the export process is still running or complete (there is a visible text on the screen, but the AutoIt window info doesn't see it; presumably it's a non standard window).

The next step is to open the pdf file in Acrobat reader or other program, using ShellExecute with the pdf filename. However, ShellExecute returns 1 whether or not the file opens. Same for Run. I'm guessing that the returned 1 is coming from Foxit Reader (which I'm using in place of Acrobat Reader) since the reader opened successfully, but Foxit reports "file not found".

I've tried looking at the output file itself. FileExists doesn't work because it's created as soon as the export process starts. I tried "Open" in binary mode, but it always returns an error even if the export is complete.

At this point the only way I can get the program to work is to use a message box for the operator to close after he sees the export process is done. Then everything works, but it's not a good solution.

What I need is a way for AutoIt to determine if another program has a file open, but I can't find it. Any suggestions

[Melba23]

Dana,

A quick Search (the facility is at top right of the page ) threw up this. I hope it is of some use.

M23

[Dana]

Thanks... I searched before posting, I really did, but used the wrong terms, I guess, didn't search on "pdf". Then I searched again, for pdf and found the same thread you posted. My bad, all is well now.

[ripdad]

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; FileInUse with Info using WMI

; example one with process
Local $proc = "AutoIt3.exe"
Local $rtn = FileInUseInfo($proc, 1)
If (Not @error) And $rtn Then MsgBox(0, 'FileInUseInfo(' & $proc & ', 1)', $rtn)

; example two with file
Local $file = @ScriptName
Local $rtn = FileInUseInfo($file, 2)
If (Not @error) And $rtn Then MsgBox(0, 'FileInUseInfo(' & $file & ', 2)', $rtn)


;##############################################################################################
; FileInUseInfo - Modify it for your needs
;
; example $mode = 1; FileInUseInfo("AutoIt3.exe", 1) ;returns file(s) used by process
;
; example $mode = 2; FileInUseInfo("SomeFile.txt", 2) ;returns process(s) using file
;##############################################################################################
Func FileInUseInfo($sInput, $mode = 1, $strComputer = "localhost")
    Local $objWMIService = ObjGet("winmgmts:\\" & $strComputer & "\root\CIMV2")
    If @error Then Return SetError(-1)
    Local $output = '', $colItems = $objWMIService.ExecQuery("SELECT * FROM Win32_Process", "WQL", 0x10 + 0x20)
    If Not IsObj($colItems) Then Return SetError(-2)
    For $objItem In $colItems
        If $objItem.CommandLine = '' Or StringLeft($objItem.CommandLine, 1) = '\' Then ContinueLoop
        If $mode = 1 And $objItem.Name = $sInput Then
        ElseIf $mode = 2 And StringInStr($objItem.CommandLine, $sInput) Then
        Else
            ContinueLoop
        EndIf
        $output &= "PID: " & $objItem.ProcessId & @CRLF
        $output &= "CommandLine: " & $objItem.CommandLine & @CRLF & @CRLF
    Next
    Return $output
EndFunc

[LeCarre]

Ya, this is an old topic, but the closest one i could find that matches my problem.

How can I tell if a file is being used by another application.

Melba's link is dead. 

Ripdad's code looked promising, but failed.

When i used Ripdad's code as is, it worked, but when i changed the $file from @Scriptname, to a .txt file that was also open in autoit (same directory), it not only did not detect the file was open, it took about 22 seconds to quietly quit.

Surely the OS must know if a file is open, and autoit surely must have a way of asking

[seadoggie01]

I think this is because text files don't have a file lock on them. You can edit and delete text files even when they are open in other applications. Try doing this with a different type of file, surely your final goal isn't to determine if a text file is open, right?

[LeCarre]

Actually it is, a bunch of data packed into a Single String, i'm using FileGetTime to detect when a file changes, but i was unsure if the file was flushed, or being written to when i read the file.  I'm getting weird results sometimes, and what appears to data that is not different as expected.

I guess i'll have to find some strategy, like read it twice over a few seconds to compare it. It's not big.

Edited September 6, 2020 by LeCarre

[Zedna]

WaitForFileReady('c:\test.txt')
MsgBox(0, 'OK', 'now file is ready ...')

Func WaitForFileReady($filename, $sleeptime = 300)
    While 1
        $file = FileOpen($filename, 1)
        If $file <> -1 Then 
            FileClose($file)
            ExitLoop
        EndIf
        Sleep($sleeptime)
    WEnd
EndFunc

 

[jchd]

40 minutes ago, LeCarre said:

read it twice over a few seconds to compare it

That doesn't prevent the situations where another process either isn't finished writing the file or reopens the file once you've read it twice (your mods will be flushed when the other process rewrites the file).

[markyrocks]

i put this is a script and compiled it...

$file=FileOpen("test.tmp",1)
$x=0

while($file)


    FileWrite($file,Random(1,9999999,1))
    $x+=1
    sleep(10)

    if $x=999 then ExitLoop


WEnd


FileClose($file)

MsgBox('','','done',10)

then i put this into a different script and ran them both at the same time....

#include <WinAPIProc.au3>
#include <WinAPI.au3>

$file=FileOpen("test.tmp",1)
$x=0

$mutex=_WinAPI_CreateMutex($file,false)

_WinAPI_WaitForSingleObject($mutex,-1)

while($file)


    FileWrite($file,"abcd")
    $x+=1
    sleep(10)

    if $x=999 then ExitLoop

WEnd

_WinAPI_CloseHandle($mutex)
FileClose($file)

It waited until the first file was finished to start writing.  Not sure if the program you're using that is competing would react the same way but for this basic test it works just fine.  

edit i even tested it with the first program not doing anything just sleeping with the file open and it the mutex still opened and wrote to the file. I have one more thing i want to test

edit: Ya even if i try to force the created mutex to take initial ownership of the object it still waits for the other to finish writing b4 proceeding.  Pretty nifty.

Edited September 7, 2020 by markyrocks

[LeCarre]

Interesting, will test that soon