Re: ORA-304500

From: Yassir Khogaly <yassir_at_khogaly.freeserve.co.uk>
Date: Thu, 19 Nov 1998 08:11:03 -0000
Message-ID: <730jvp$d64$1@newsreader1.core.theplanet.net>

Problem Description

Calling a Windows API function from Oracle Forms using the ORAFFI (foreign function interface) the user receives the following error:

FRM-40735: Unhandled Exception ORA-304500.

Problem Background

This code worked in the 16-bit version of Oracle*Forms for Windows 3.1x. The
user started getting this error after upgrading to the 32-bit version of Forms
on Windows 95 or NT.

Solution Description

Change the name of the dll in the ORA_FFI.FindLibrary and ORA_FFI.LoadLibrary calls to reflect the 32 bit equivalent.
Change any function name in the ORA_FFI.Register_Function call which may be different from its 16 bit name.

Solution Background

The error message is most likely due to Oracle*Forms not being able to find the specified function in the specified library (.dll). The names of the library files have changed from 16 bit windows to 32 bit windows:

   16 Bit Windows               32 Bit Windows NT/95
   ==============               ====================
   USER.EXE                     USER32.DLL
   KRNL386.EXE                  KERNEL32.DLL
   GDI.EXE                      GDI32.DLL

Also, the some of the names of the functions implemented in these libraries have been changed by Microsoft. For example, WinHelp has been changed to WinHelpA. The following is an incomplete list of function names that have changed:

   16 Bit Windows               32 Bit Windows NT/95
   ==============               ====================
   WinHelp                      WinHelpA
   GetPrivateProfileString      GetPrivateProfileStringA
   WritePrivateProfileString    WritePrivateProfileStringA
   FindWindow                   FindWindowA
   ExpandEnvironmentStrings     ExpandEnvironmentStringsA
   GetWindowsDirectory          GetWindowsDirectoryA
   GetTempPath                  GetTempPathA
   GetTempFileName              GetTempFileNameA
   DeleteFile                   DeleteFileA

Step 1:
Substitute the 16 bit Windows library name with the equivalent 32 bit Windows
NT or Windows 95 library name in your PL/SQL code (program unit or .PLL file).

Step 2:
If the function name has not been changed by Microsoft, the step 1 will fix the error. In case you still get the "FRM-40735: Unhandled Exception ORA-304500" error message, then you need to find out if the function name has
been changed. Use a utility, such as DUMPBIN provided with Microsoft Visual C++, that lets you determine the function names exported by a .dll file. Subsitute any changed function name in the ORA_FFI.Register_Function call in your PL/SQL Code.

(HINT: If the Windows API function you are calling is not listed above and you do not have access to a 32 bit C compiler, try appending the letter "A" to
the function name. This will most likely resolve the problem.)

For more information regarding why the names of the functions have been changed please refer to documentation provided by Microsoft. Received on Thu Nov 19 1998 - 02:11:03 CST