The information in this article applies to:
- Microsoft Win32 Software Development Kit (SDK) for Windows 95 3.51
SUMMARY
This article describes the major differences between the Win32 Data Link
Control (DLC) API as implemented on Windows 95 and Windows NT. It assumes
familiarity with the DLC protocol and the relevant specification documents.
It also assumes familiarity with the following Microsoft Knowledge Base
article that describes the differences between Windows NT DLC and the IBM
Specifications for OS/2 1.xx:
ARTICLE_ID: Q156081
TITLE : Differences between Data Link Control APIs on
Windows NT & DOS
MORE INFORMATION
The differences between Windows 95 and Windows NT DLC are as follows:
- The Windows 95 API continues to use the CCB Application ID field. In
Windows NT and DLCAPI.H, this field is defined as uchReserved2 in the
LCC_CCB structure and is commented as reserved for DLC DLL. A Windows 95
application must use this field as defined for OS/2 EE. That is:
- Issue a DIR.OPEN.ADAPTER command with this CCB set to zero. The DLC
driver will set this field to an Application ID value.
- This Application ID must be used in subsequent CCB requests by
setting uchReserved2 to this value.
This difference is necessary because Windows 95 does not have support for
the security mechanisms used by Windows NT in lieu of the application ID.
See The IBM LAN Technical Reference Manual for more information.
- The fields uchReserved1 and uchReserved3 must not be used by an
application under any circumstances.
- NT-specific extensions such as security, multiple processors, or
international character strings are not supported.
- Windows 95 continues to support the completion method of polling (busy
looping) on the CCB's return code (uchDlcStatus in the LLC_CCB
structure). This method is not reliable on Windows NT and an application
that uses it on Windows 95 may not work on Windows NT.
- Windows 95 allows a DIR.STATUS command to be issued before a
DIR.OPEN.ADAPTER CCB. NT does not allow this. You should be aware of
this when writing cross-platform applications.
- Windows 95 does not support:
- Multiple logical adapters.
- TRANSMIT.FRAMES.CCB.
- Direct station support that is global to all applications.
- The Windows 95 802.2 implementation does support CCB 1's or a 16-bit
DOS interface.
- An application must issue a BUFFER.CREATE command before issuing any of
the following CCBs:
BUFFER.FREE DLC.OPEN.SAP XMIT.I.FRAME
BUFFER.GET DLC.OPEN.STATION XMIT.DIR.FRAME
DIR.CLOSE.DIRECT DLC.REALLOCATE XMIT.TEST.CMD
DIR.OPEN.DIRECT DLC.RESET XMIT.UI.FRAME
DLC.CLOSE.SAP DLC.STATISTICS XMIT.XID.CMD
DLC.CLOSE.STATION READ XMIT.XID.RESP.FINAL
DLC.CONNECT.STATION READ.CANCEL XMIT.XID.RESP.NOT.FINAL
DLC.FLOW.CONTROL RECEIVE
DLC.MODIFY RECEIVE.CANCEL
REFERENCES
- IBM LAN Technical Reference SC30-3383. This describes the basic set of
CCB2 functions as used by OS/2 EE.
- DLCAPI.H
- For more information, please see the following article in the Microsoft
Knowledge Base:
ARTICLE_ID: Q156081
TITLE : Differences between Data Link Control APIs on
Windows NT & DOS