The behavior of Win32::OLE->new

[marynella]

I have an existing problem with Perl/OLE, that I'd like you to take a look at. In my script there is a call to:

Win32::OLE->new( 'InternetExplorer.Application', sub {$_[0]->Quit;} )

It appears that the behavior of Win32::OLE->new is as follows:

1. If there is an existing instance of InternetExplorer(IE) running, then it will return a handle to the existing IE application.
2. If there is not an existing instance of IE running, then it will create a new instance of IE, and return a handle to this new instance.

I seem to be having a concurrency/race condition problem with this call, when multiple scripts get the same instance of IE for the handle. Can you help me to find a way to change this call, so that it ALWAYS returns a new instance of IE and does not try to look for an already existing instance of IE?

Note: I am currently using Win32::Mutex to avoid the concurrency/race condition problems. However, this is not the best solution.
Thanks!

update (broquaint): tidied up formatting

[l3nz]

This is not much a Perl-ish answer, but I guess it's not mostly a Perl problem - this is probably because of the threading model the object is running under. I have come across the same problem with VisualBasic and JavaScript object creation, and I have found that, to obtain different and separate independent copies, you can:
• Create an object of type WScript.Shell
• Call the "run" method on it to launch a separate browser (or whatever program you need to run)
This is a sample, just not to go completely off-topic and being thrown out of the monastery for messing with the Enemy without providing appropriate Perl code as an offer:

use Win32::OLE;
my $url = 'http://www.perlmonks.com/index.pl?node_id=';

# opens five separate instances
for (my $i = 0; $i < 5; $i++ ) {
    my $node_id = 300000 + $i;
    $obSh = Win32::OLE->new('WScript.Shell');
    $rc   = $obSh->run("IEXPLORE.EXE ${url}${node_id}", 1, false);
    undef $obSh;
}

On my Windows box, each copy of explorer is independent and separately prompts for the proxy password.

You might want to read this too.

[marynella]

  Your solution maybe good, but I have another problem. Maybe someone had this new problem to and can help me.
I've put in my script the line:
  $obSh = Win32::OLE->new('WScript.Shell', sub {$_[0]->Quit;}) or die "Can't start Shell", Win32::OLE::LastError();
This line gives me an error:
  Can't start ShellWin32::OLE(0.17) error 0x80040154: "Class not registered"
Thanks!

[jsprat]

You want a new instance of IE every time it runs, right?

Instead of Win32::OLE->new(), what you want to use is CreateObject, like so:

my $ie = Win32::OLE->CreateObject('InternetExplorer.Application', 'Qui
+t')
    or die "Can't start IE", Win32::OLE::LastError();

$ie in each script will reference its own instance of IE.

Update: According to Win32::OLE docs, new and CreateObject are equivalent. You should be getting a new instance of ie with each run.

[marynella]

If instead of Win32::OLE->new(), I use CreateObject my problem is not solved.
Thanks any way for the advice

[jsprat]

Hmm. On Win2K/IE6 and Win98/IE5.5, both l3nz snippet and mine work for me, and you don't have Windows Script Host.

What version of Windows and IE are you running?

[meredith]

Is it possible this is related to the "Reuse windows when launching shortcuts" option? In the Internet Options control panel, look in the Advanced tab. Since the ShellExec of a .url file basically does the same thing you're doing, this may have an effect on your problem.