who sets DISPLAY_DEVICE_ATTACHED_TO_DESKTOP/DISPLAY_DEVICE_MIRRORING_DRIVER flag.

NTDEV
1

Hi,
I was looking into some code and found DISPLAY_DEVICE_ATTACHED_TO_DESKTOP
/ DISPLAY_DEVICE_MIRRORING_DRIVER flags are being used to check how many
monitors are active but my doubts are who is setting these flags, on what
all circumstances it will get set and what they signify.

May be this is a basic question but I did not have answers.

Any input will be highly appreciable.

2

Sarbojit Sarkar wrote:

I was looking into some code and found
DISPLAY_DEVICE_ATTACHED_TO_DESKTOP / DISPLAY_DEVICE_MIRRORING_DRIVER
flags are being used to check how many monitors are active but my
doubts are who is setting these flags, on what all circumstances it
will get set and what they signify.

May be this is a basic question but I did not have answers.

Surely you can figure this out. Did you even look at the
documentation? This is a documented structure (DISPLAY_DEVICE), and
those bits are described. DISPLAY_DEVICE_ATTACHED_TO_DESKTOP is the
same as DISPLAY_DEVICE_ACTIVE.

–
Tim Roberts, xxxxx@probo.com
Providenza & Boekelheide, Inc.

3

Yes, I have gone through Display_device documentation on MSDN but I was
looking for some more detailed documentation. Please let me know if there is
any.

On Tue, Apr 12, 2011 at 9:46 PM, Tim Roberts wrote:

> Sarbojit Sarkar wrote:
> >
> > I was looking into some code and found
> > DISPLAY_DEVICE_ATTACHED_TO_DESKTOP / DISPLAY_DEVICE_MIRRORING_DRIVER
> > flags are being used to check how many monitors are active but my
> > doubts are who is setting these flags, on what all circumstances it
> > will get set and what they signify.
> >
> > May be this is a basic question but I did not have answers.
>
> Surely you can figure this out. Did you even look at the
> documentation? This is a documented structure (DISPLAY_DEVICE), and
> those bits are described. DISPLAY_DEVICE_ATTACHED_TO_DESKTOP is the
> same as DISPLAY_DEVICE_ACTIVE.
>
> –
> Tim Roberts, xxxxx@probo.com
> Providenza & Boekelheide, Inc.
>
>
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4

Sarbojit Sarkar wrote:

Yes, I have gone through Display_device documentation on MSDN but I
was looking for some more detailed documentation. Please let me know
if there is any.

It’s hard to know what else they could say. The definition of an
“active display” and a “mirrored display” seem unambiguous to me.

–
Tim Roberts, xxxxx@probo.com
Providenza & Boekelheide, Inc.