How To Call GDI Functions from a Print Driver

ID: Q151891

The information in this article applies to:

SUMMARY

A print driver can call GDI functions having the same name as printer- driver entry-point functions by explicitly or implicitly reloading GDI.

MORE INFORMATION

Windows 95 printer drivers export functions that have the same name as the GDI functions. In order to call the GDI functions from a printer driver, such as BitBlt, ExtTextOut, etc., do the following:

1. Import the GDI functions in the .DEF file under the IMPORTS section of

   the driver's .DEF file and use the imported function names.

2. Do a LoadLibrary on GDI.EXE and obtain the address of the desired
   function to be called using the GetProcAddress function. Once the
   address is obtained, the function can be called using the function
   pointer.

3. Define a DLL with functions that will call the GDI functions and IMPORT
   the DLL functions in the printer driver. For example, to call a GDI
   function, you would call the corresponding function in the DLL that, in
   turn, would make the GDI function call.

Additional query words: debugging print driver
Keywords          : kbDDK kbPrinting 
Version           : 4.00
Platform          : WINDOWS

Last Reviewed: June 26, 1998