PRB: "API Call Caused an Exception" Error Message with Third-Party Print Drivers (253356)

The information in this article applies to:

Microsoft Visual FoxPro for Windows 6.0, when used with:
- the operating system: Microsoft Windows 95
- the operating system: Microsoft Windows 98

This article was previously published under Q253356

SYMPTOMS

When using a Hewlett Packard LaserJet 4000 PCL5e or other third-party print driver, a non-fatal error can occur:

API call caused an exception

CAUSE

The third-party print drivers are not resetting the floating point coprocessor.

RESOLUTION

Here is a workaround to the behavior. The error message "API call caused an exception" is trappable and reports an error number of 2028. The error can be handled by placing an _fpreset() function call and a retry command in an error-handling procedure. The following code demonstrates the basic structure for trapping this error:

DECLARE _fpreset IN MSVCRT20.DLL
ON ERROR DO errHand WITH ERROR()
SET LIBRARY TO HOME()+"foxtools.fll"
SET PRINTER TO GETPRINTER()
? _wfindtitl("Command") && Error occurs at this point

PROCEDURE errHand
PARAMETERS _lcError
   DO CASE
       CASE _lcError = 2028 && API call caused an exception
	       _fpreset()
	       RETRY
       OTHERWISE
               ERROR _lcError
       ENDCASE
ENDPROC

STATUS

This behavior is by design.

MORE INFORMATION

Steps to Reproduce the Behavior

Install a HP LaserJet 4000 PCL5e print driver.

Copy the following code into a FoxPro program:

SET LIBRARY TO HOME()+"FOXTOOLS.FLL"
SET PRINTER TO GETPRINTER()
? _wfindtitl("command")

Execute the new program.
Choose the HP LaserJet 4000 PCL5e print driver. The error message listed in the "Symptoms" section is displayed.

REFERENCES

For additional information, click the article number below to view the article in the Microsoft Knowledge Base:

183522 FIX: Divide by Zero Creates Err with Third-Party Print Drivers

182137 PRB: Memory Error with HP LaserJet 4000 TN PCL 5e Driver

Modification Type:	Major	Last Reviewed:	11/17/2003
Keywords:	kb3rdparty kbprb kbprint KB253356