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List:       ms-smartcardsdk
Subject:    Re: undocumented attributes
From:       Doug Barlow <dbarlow () MICROSOFT ! COM>
Date:       1999-05-12 18:47:44
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Any attribute may be used from an application, via the SCardGetAttr()
service.  (However, there's no guarantee that Set Attribute commands won't
break things.)

I'll let Klaus answer the meaning of the rest, but the values:

SCARD_ATTR_DEVICE_FRIENDLY_NAME
SCARD_ATTR_DEVICE_SYSTEM_NAME

when used from SCardGetAttr() are intercepted by the Resource Manager, and
not forwarded to the driver.  They return the system name of the reader
(<vendor> <model> <unit>)  and the friendly names of the reader,
respectively.

SCARD_ATTR_DEVICE_IN_USE is used by the Resource Manager to inform drivers
as to whether or not applications are actively using them.  It is used only
in a Set Attribute IOCTL.  It's value is a DWORD: 0 implies no applications
are using the device, and 1 implies at least one application is using the
device.  It can be used for special purpose power management.  If the driver
returns an error to the Set Attribute IOCTL command, then the resource
manager doesn't bother to inform your driver of such changes in the future.
Hence, if you don't support it, it will leave you alone.

Doug Barlow
Microsoft Corporation

 -----Original Message-----
From:   Vladimir Beker [mailto:bwz@ARX.COM]
Sent:   Wednesday, May 12, 1999 8:03 AM
To:     SmartCardSDK@DISCUSS.MICROSOFT.COM
Subject:        undocumented attributes

There are some attributes in WINSMCRD.H that I didn't found in
specifications:
SCARD_ATTR_EXTENDED_BWT
SCARD_ATTR_CURRENT_IO_STATE
and all attributes of class SCARD_CLASS_SYSTEM

What they are and how to deal with them?
May I ask for them from application?
How I suppy them from the driver?
Vladimir


> -----Original Message-----
> From: Doug Barlow [SMTP:dbarlow@MICROSOFT.COM]
> Sent: Wed, May 12, 1999 5:51 PM
> To:   SmartCardSDK@DISCUSS.MICROSOFT.COM
> Subject:      Re: Transaction cancelling & multiple reader names
>
> 1) There's a few differences between the Microsoft implementation and the
> PC/SC specification due to the implementation being done in parallel with
> the specification.  The ability to cancel a transaction request was one of
> those differences.  I think it's a great idea; I just haven't had time to
> put it in yet.
> 2) That's an interesting bug; I think I know what's doing it.  I'll look
> into it further.  Is this platform Windows NT or Windows 9x?
>
> Doug Barlow
> Microsoft Corporation
>
>  -----Original Message-----
> From:   Vizvary Istvan, jr. [mailto:vizyj@HOTMAIL.COM]
> Sent:   Wednesday, May 12, 1999 6:00 AM
> To:     SmartCardSDK@DISCUSS.MICROSOFT.COM
> Subject:        Transaction cancelling & multiple reader names
>
> I have two questions:
> 1) How to cancel a waiting transaction request after calling
> SCardBeginTransaction? This is specified as possible in the PCSC
> specification but does not seem to be implemented in Windows.
> 2) When using SCardGetStatusChange if among the reader names specified
> there
> are two or more (even different) names of one physical device, an error
> code
> is returned. How is this effect explained?
>
> Vizvary Istvan, jr.
> vizyj@hotmail.com

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