SAMPLE: Wsscanf.exe Replaces sscanf in Windows DLLs

ID: Q76684

The information in this article applies to:

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

SUMMARY

Wsscanf.exe that can serve as a limited replacement for the Microsoft C run- time library function sscanf, which is not compatible for use with a dynamic-link library (DLL) for the Microsoft Windows graphical environment.

MORE INFORMATION

The following file is available for download from the Microsoft Download Center. Click the file name below to download the file:

Wsscanf.exe

For more information about how to download files from the Microsoft Download Center, please visit the Download Center at the following Web address

http://www.microsoft.com/downloads/search.asp

and then click How to use the Microsoft Download Center.

The sscanf(), fprintf(), and scanf() functions are not available for Windows DLLs.

There are two factors that cause these functions to be incompatible:

These functions rely on near pointers.

These functions expect SS == DS.

Because neither of these conditions is true when a function in a DLL uses data from an application, these functions are not available.

The WSSCANF file in the Microsoft Download Center contains the source code to a wsscanf() function that can serve as a limited replacement for the sscanf function. It does not support floating point. The wsscanf() code is based on the sscanf() source code in the Microsoft C 6.0a run-time library. The source code has been modified to work correctly in a DLL, and requires that all parameters are specified as FAR pointers. The following code demonstrates using the wsscanf() function:


    char   szBuf[] = "1 3 b000:0200";
   int    nValue1, nValue2;
   LPSTR  lpPtr;

   wsscanf(szBuf, "%d %d %p", (int FAR *)&nValue1,
            (int FAR *)&nValue2, (LPSTR FAR *)&lpPtr);

NOTE: The first two parameters are not explicitly typecast in the function call. The function prototype typecasts the first two parameters automatically; however, the application must typecast each subsequent parameter. If the application does not typecast each parameter, when the application calls wsscanf an unrecoverable application error (UAE) occurs.

The wsscanf() function does not support floating point numbers (the %f, %g, and %e format specifiers).

Additional query words:

Keywords : kbfile kbsample kb16bitonly
Version : WINDOWS:3.0,3.1
Platform : WINDOWS
Issue type :