DOCUMENT:Q75255  05-NOV-1999  [win16sdk]
TITLE   :INFO: DBCS Support in Windows Versions 3.0 And 3.1
PRODUCT :Microsoft Windows Software Development Kit
PROD/VER:WINDOWS:3.0,3.1
OPER/SYS:
KEYWORDS:kbIntlDev

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The information in this article applies to:

 - Microsoft Windows Software Development Kit (SDK) versions 3.1, 3.0 
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SUMMARY
=======

In a version of Windows that is enabled for double-byte character sets (DBCS),
all functions that take strings as arguments will work with strings of
double-byte characters. In addition, any version of Windows that supports DBCS
will support the IsDBCSLeadByte function. This function determines whether or
not a byte is the leading byte of a 2-byte character. The Windows functions that
use a string length parameter (like lstrlen and TextOut) will use a count of
bytes, not of characters. The functions IsDBCSLeadByte, AnsiPrev, and AnsiNext
should be used to access characters within a string.

Note that DBCS-enabled Windows will typically have special methods to enter
double-byte or composite characters. Composite character creation involves
pressing several keys in a specified sequence to form new characters. The entry
system is integrated into Windows by the original equipment manufacturer
(hardware OEM). These characters are not typically directly entered into an edit
control. Composite characters may be entered at the bottom of dialog box (as in
OS/2). In many systems, these characters are composed at the bottom of the
screen (in the composition window).

Copies of Windows version 3.0 developed for the United States and Europe do not
support DBCS. Copies of Windows version 3.1 developed for the United States and
Europe, and the KANJI adaptation of Windows version 3.0 and 3.1 do support DBCS.
The KANJI adaptation of Windows is distributed through hardware OEMs. For more
information on KANJI Windows, search this knowledge base on the following
words:

   " KANJI " (without the quotation marks)

The March, 1990, "Microsoft Systems Journal" article "Using the OS/2 National
Language Support Services to Write International Programs" has more information
on both DBCS and KANJI. It can be found in the Software/Data Library by
searching on OS2NLS or S12547. OS2NLS was archived using the PKware
file-compression utility.

Additional query words:

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Keywords          : kbIntlDev 
Technology        : kbAudDeveloper kbWin3xSearch kbSDKSearch kbWinSDKSearch kbWinSDK300 kbWinSDK310
Version           : WINDOWS:3.0,3.1
Issue type        : kbinfo

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