StdoutRead freezes

[VAN0]

Hello.

I've tried search the forum and found few topic with the same issues, but none of them have working solution for me.

I have the following code:

Local $line = ""
Local $foo = Run(@ComSpec & " /c powercfg -list", @SystemDir, @SW_HIDE, $STDERR_CHILD + $STDOUT_CHILD)
While 1
   $line &= StdoutRead($foo)
   If @error Then ExitLoop
WEnd

If I put this in a loop, after a while it freezes in the infinite loop because StdoutRead doesn't through @error

I'm not quiet understand how this piece of code actually works and the only workaround solution I can think of is instead of creating infinite loop, use counter to let say 10000 loops, but this will fail on super fast computers I guess:

$i = 10000
Local $line = ""
Local $foo = Run(@ComSpec & " /c powercfg -list", @SystemDir, @SW_HIDE, $STDERR_CHILD + $STDOUT_CHILD)
Do
    $line &= StdoutRead($foo)
    If @error Then ExitLoop
    $p = ProcessExists($foo)
    If Not $p Then $i -= 1
Until Not $i

The second code works for me so far, but is there a "proper" way handle this issue when StdoutRead indefinitely waiting for output?

Thank you.

P.S.

suggested using sleep() would affect on script performance, so I'd rather avoid it too.

Edited February 10, 2013 by VAN0

[JohnOne]

Not quite an expert on this but does the window close after operation?

If so

While ProcessExists($foo)
   $line &= StdoutRead($foo)
   If @error Then ExitLoop
WEnd

or

While ProcessExists($foo)
   Sleep(10)
WEnd
$line = StdoutRead($foo)

[guinness]

Here's how I would do it.

; Example 1
Local $sOutput = ''
While 1
    $sOutput &= StdoutRead($iPID) ; Read the standard output stream.
    If @error Then ; This will exit the loop if the process doesn't exists.
        ExitLoop
    EndIf
WEnd

; Example 2
ProcessWaitClose($iPID) ; Wait for the process to close.
Local $sOutput = StdoutRead($iPID) ; Read the standard output stream.

[garbb]

I had the same problem of stdoutread() hanging up intermittently in my script. I made it run in a loop and usually it would only run a few hundred times before stdoutread() would freeze. This is the best I could come up with: 

Local $foo = Run(@ComSpec & " /c dir foo.bar", "C:\", @SW_HIDE, $STDERR_CHILD + $STDOUT_CHILD + $RUN_CREATE_NEW_CONSOLE)
Do
until NOT ProcessExists($foo)
Local $line = StdoutRead($foo)
StdioClose($foo)
ConsoleWrite("STDOUT read:"&' "'&$line&'"'&@CR)

It seems to run forever without freezing. For some reason if you use "ProcessWaitClose($foo)" it will make the script much slower that if you use "Do

until NOT ProcessExists($foo)" even though I would think that they are doing the exact same thing.

Also don't forget to use StdioClose($foo) or you will probably have a memory leak. (I definitely did)

I know that this is an old thread but I happened across it when searching for a solution to my problem and so hopefully someone else will in the future.