Article: Q67675
Product(s): Microsoft Windows Software Development Kit
Version(s): WINDOWS:3.0,3.1
Operating System(s):
Keyword(s): kb16bitonly
Last Modified: 06-NOV-1999
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The information in this article applies to:
- Microsoft Windows Software Development Kit (SDK) versions 3.0, 3.1
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SUMMARY
=======
Windows real and standard modes do not provide an interface for standard MS-DOS
(non-Windows) applications to access the Windows clipboard. However, in Windows
enhanced mode, access is provided through the INT 2fh interface. This article
discusses various methods that may be used to simulate clipboard access in real
and standard modes and documents the INT 2fh interface for enhanced mode.
MORE INFORMATION
================
Under Windows real and standard modes, it is possible to simulate programmatic
access to the contents of the clipboard by a standard MS-DOS-based application.
One possible method is to create a Windows-based application that places the
contents of the Windows clipboard into a file. The MS-DOS-based application
would check for the existence of the file saved from the Windows-based
application. When the file exists, the MS- DOS-based application can read the
contents, eliminating the necessity for direct user intervention on behalf of
the MS-DOS-based application.
Only textual information can be retrieved from the clipboard by a standard
MS-DOS-based application. This is done using the Edit Paste hierarchical system
menu combination in Windows enhanced mode that is available when the
MS-DOS-based application is windowed.
In Windows real or standard modes, a Paste option can be selected directly from
the system menu only when the MS-DOS-based application is represented by an icon
("iconic"), giving the user access to its system menu. When Paste is selected,
Windows will restore the MS-DOS-based application to full screen and paste the
contents of the clipboard where the cursor is located in the MS-DOS-based
application. MS-DOS-based applications can be made iconic in real and standard
modes through an ALT+TAB keystroke.
Placing information into the clipboard can be done though the use of the PRINT
SCREEN or ALT+PRINT SCREEN keystrokes, each of which copies a full screen into
the clipboard.
Copying information to the Windows clipboard can be done in Windows enhanced mode
using the Edit Mark and Edit Copy system menu commands.
More information on user control of the Windows Clipboard can be found on pages
440-490 in the "Microsoft Windows User's Guide," Chapter 12.
The remainder of this article documents the INT 2fh interface to the clipboard,
available in Windows enhanced mode.
NOTE: The Windows functions RegisterClipboardFormat() and EnumClipboardFormats()
are not supported.
Function Call Definitions
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Name IdentifyWinOldApVersion()
Parameters AX = 1700H
Return Values AX == 1700H: Clipboard functions not available
<> 1700H: AL = Major version number
AH = Minor version number
Name OpenClipboard()
Parameters AX = 1701H
Return Values AX == 0: Clipboard already open
<> 0: Clipboard opened
Name EmptyClipboard()
Parameters AX = 1702H
Return Values AX == 0: Error occurred
<> 0: OK, Clipboard emptied
Name SetClipboardData()
Parameters AX = 1703H
DX = WinOldAp-Supported Clipboard format
ES:BX = Pointer to data
SI:CX = Size of data in bytes
Return Values AX == 0: Error occurred
<> 0: OK. Data copied into allocated memory.
Note The MS-DOS-based application should call the
ClipboardCompact() function prior to this to determine
if the data can be accommodated in memory.
Name GetClipboardDataSize()
Parameters AX = 1704H
DX = WinOldAp-Supported Clipboard format
Return Values DX:AX == Size of the data in bytes, including any
headers.
== 0 If data in this format is not in the clipboard.
Name GetClipboardData()
Parameters AX = 1705H
DX = WinOldAp-Supported Clipboard format
ES:BX = Pointer to data buffer to hold data
Return Values AX == 0: Error occurred (or data in this format is not
in the clipboard)
<> 0: OK
Note This call should be preceded by a
GetClipBoardDataSize() call to find out how much memory
is required for the buffer. No checking is performed, the
caller must ensure that the buffer is big enough;
otherwise, some of the callers code or data may be
overwritten.
Name CloseClipboard()
Parameters AX = 1708H
Return Values AX == 0: Error occurred
<> 0: OK
Name ClipboardCompact()
Parameters AX = 1709H
SI:CX = Desired memory size in bytes.
Return Values DX:AX == Number of bytes of largest block of free memory.
== 0 if error or no memory
Notes The MS-DOS-based application is responsible for including
the size of any headers in the desired memory size.
Name GetDeviceCaps()
Parameters AX = 170AH
DX = GDI information index
Return Values AX == integer value of desired item
== 0 if error
Notes The implied hDC for this call will be for the display.
Supported Clipboard Formats
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The following Windows clipboard formats are supported:
CF_TEXT = 1
CF_BITMAP = 2 ; See structures section
CF_OEMTEXT = 7
CF_DSPTEXT = 81h
CF_DSPBITMAP = 82h
NOTE: Since the RegisterClipboardFormat() and EnumClipboardFormats() functions
are not available at this time, the use of private clipboard formats is not
supported.
Structures
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These structures mimic the actual Windows structures with one major difference:
instead of including a handle or pointer to other memory containing the actual
data, the data follows the structure. The structure information now behaves like
a header prefacing the data.
Bitmap structure:
bmType DW ? ; Always 0
bmWidth DW ? ; Width of bitmap in pixels
bmHeight DW ? ; Height of bitmap in raster lines
bmWidthBytes DW ? ; Bytes/raster line
bmPlanes DB ? ; Number of color planes in the bitmap
bmBitsPixel DB ? ; Number of adj color bits to def pixel
bmBits DQ ? ; Points to byte following bmHigDim
bmWidDim DW ? ; Width of bitmap in 0.1 mm units
bmHigDim DW ? ; Height of bitmap in 0.1 mm units
BitmapData nBytes ; The actual data
Additional query words: 3.00 3.10
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Keywords : kb16bitonly
Technology : kbAudDeveloper kbWin3xSearch kbSDKSearch kbWinSDKSearch kbWinSDK300 kbWinSDK310
Version : WINDOWS:3.0,3.1
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