Oracle Forms WebUtil Functions FAQ

WebUtil provides a simple way to achieve client side integration while running Oracle Forms on the Web. It simplifies the upgrade of existing applications to the web, and enhances the capabilities of Web based Oracle Forms applications.  It is a utility that any Forms developer could use to carry out the complex tasks on the client browser machines by simply coding PL/SQL. With WebUtil, everything the programmer needs to do is exposed through a PL/SQL library.

This FAQ answers the questions that are often asked about WebUtil's functions.

1)
Q:  Can the file functions use Universal Naming Convention (UNC)?
A:  No.

2)
Q:  CLIENT_TEXT_IO.PUT_LINE terminates lines with a Unix LF, and not CR/LF on Windows
A:  This is a known issue in 1.0.5 and 1.0.6, and has been logged as Oracle Bug 3925548. A workaround is listed in the bug.

3)
Q:  Calling Invoke_String for a C function that returns type (char), but it does not work.
A:  Strings in C are character arrays, hence the function should return a (char *) type. If the C function returns (char), use Invoke_Char instead. Note that 1.0.5 has a problem with Invoke_Char which will be resolved in a future release. Currently the workaround is to redefine the C function to return (int) or (char *).

4)
Q:  Can the C API in WebUtil call a function that needs a window handle? E.g. most scanner interface functions require a window handle as a parameter.
A:  No.

5)
Q:  Can the C_API call C functions that usa a PASCAL calling convention?
A:  Unfortunately not.

6)
Q:  My old ORA_FFI implementation worked fine. But my C_API implementation in WebUtil crashes.
A:  Most of the times this indicates a parameter-type mismatch. Typically a parameter in the C function has been declared as a pointer type e.g. (int *) or HANDLE, and C_API is then told that it is a plain type e.g. (int).

7)
Q:  Is there a WebUtil equivalent of the D2KWUTIL WIN_API_SHELL.SENDKEYS function?
A:  No, as JDK 1.4 is needed for this functionality, and WebUtil 1.0.5 was built with JDK 1.3.1. A future version of WebUtil might include this, depending on enhancement requests logged.

8)
Q:  Can Borland created DLLs be used in the C API?
A:  Borland and Microsoft produce different library formats. As with ORA_FFI, only the Microsoft format can be used.

9)
Q:  Is there an equivalent WIN_API_UTILITY.InterruptCheck call in WebUtil as there was in d2kwutil?
Q:  As of WebUtil 1.0.6, no.

10)
Q:  Can WebUtil interface with DDE?
A:  No, use OLE or the C API instead.

11)
Q:  How to use WEBUTIL_FILE.DIRECTORY_LIST?
A:  An example is included in the WebUtil demos, available from the Oracle WebUtil Home Page .

12)
Q:  Does WebUtil provide equivalents of all the functions included in the demo utility D2KWUTIL?
A:  No, only selected functions have been implemented. Please check the WebUtil documentation to be sure.