KB185865 - FIX: Printing reports in a loop hangs Visual FoxPro

Article ID: 185865

Article Last Modified on 2/11/2005

Microsoft Visual FoxPro 3.0 Standard Edition
Microsoft Visual FoxPro 3.0b Standard Edition
Microsoft Visual FoxPro 5.0 Standard Edition
Microsoft Visual FoxPro 5.0a
Microsoft Visual FoxPro 6.0 Professional Edition

This article was previously published under Q185865

SYMPTOMS

Printing reports in loops generates an "Internal Consistency" error under Windows 95 and hangs Visual FoxPro under Windows NT 4.0.

CAUSE

This activity causes massive amounts of spooling, which causes a low memory situation because of continuous virtual memory swapping.

RESOLUTION

Create an out-of-process Visual FoxPro OLE server to handle the printing and release the object when the printing is completed. This workaround is available only in versions of Visual FoxPro later than 3.0x.

An example is shown below.

Create an OLE server named "TestPrint" by creating a project, adding the following code to a program file, and compiling the project to an EXE file:

   DEFINE CLASS PrintIt AS CUSTOM OLEPUBLIC

   WhichData=''
   WhichReport=''

   PROCEDURE PRINTOUT
      Use (This.WhichData)
      REPORT FORM (This.WhichReport) to Print
      Use
   ENDPROC

   ENDDEFINE

In your application, replace the REPORT FORM command with the following lines of code:

   Ox=CreateObject("TestPrint.PrintIt")
   Ox.WhichData  ="<Full Path of the Table associated with the report>"
   Ox.WhichReport="<Full Path of the Report>"
   Ox.PRINTOUT
   Release OX

STATUS

Microsoft has confirmed that this is a bug in the Microsoft products that are listed at the beginning of this article.

This bug was corrected in Visual Studio 6.0 Service Pack 3.

MORE INFORMATION

WARNING: Close all running applications and save your data before following this procedure. Note that following these steps may produce lost allocation units, lost clusters, or cross-linked files.

Steps to Reproduce Behavior

Create a table named Test and insert some records.

      CREATE TABLE Test (ID c(4), NAME c(20))
      INSERT INTO Test VALUES ("AAA","111")
      INSERT INTO Test VALUES ("BBB","222")
      INSERT INTO Test VALUES ("CCC","333")

Create a Quick Report based on table Test and name the report Test.frx.

Place the following code in a program and run the code:

      SET SAFETY OFF
      FOR i=1 TO 5000
         ?? i
         REPORT FORM Test TO FILE Test.txt ASCII
      NEXT

The system hangs or crashes after a certain number of iterations.

Additional query words: kbDSE VFP600REL

Keywords: kbbug kbfix kbprint KB185865