Kleopatra locking the Clipboard

[Marc Mutz]

HI Andrew,

On Wednesday November 2 2011, Andrew Birch wrote:
> Application: Kleopatra (Certificate Manager and Unified Crypto GUI)
> Version: 2.1.0
> KDE Version: 4.1.4
>
> I am a developer who is working on a piece of software that accesses the
> Clipboard. I am experiencing a problem whereby when trying to access the
> Clipboard an ExternalException is thrown with the following error message:
> 'The requested clipboard operation did not succeed'. As a result, I did
> some diagnostic work to try to work out which application was locking the
> Clipboard. There seem to be a number of different applications that
> sometimes lock it (presumably whilst they have access to it).
>
> However, the worst offender seems to be Kleopatra.exe. By 'worst' I mean it
> seems to persistently lock the Clipboard and thus blocks our application
> from accessing it. We are not actively using Kleopatra when this problem
> occurs; it is just running in the background. Also, interestingly this
> problem does not always seem to happen; sometimes Kleopatra doesn't seem to
> access/lock the Clipboard.
>
> I was wondering if you might know why this is and if there is anything we
> can do to prevent Kleopatra.exe from persistently accessing the Clipboard?

What Kleopatra does, in technical terms, is to connect to QClipboard's 
changed() signal and queries the data in there to see whether it should 
enable/disable it's clipboard-related actions.

So when you're talking about locking the clipboard, I'm sure that's something 
that QClipboard does internally. Not knowing the Windows APIs for this, I 
can't be of much help here.

Maybe some of the Windows specialists know more?

Thanks,
Marc

-- 
Marc Mutz <marc.mutz at kdab.com> | Senior Software Engineer
KDAB (Deutschland) GmbH & Co.KG, a KDAB Group Company
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