BUG: REPLACE with UDF May Cause "Record Is Not Locked" Error

ID: Q142397

The information in this article applies to:

Microsoft Visual FoxPro for Windows, versions 3.0, 3.0b, 5.0, 5.0a, 6.0

SYMPTOMS

Using a user-defined function (UDF) that moves the record pointer in the currently selected table with a REPLACE command causes a "Record is not locked" error message. This error occurs if the buffering property is set to 2-Pessimistic record, 3-Optimistic record, or 5-Optimistic table.

WORKAROUND

Set the buffering property to 4-Pessimistic table. This locks the record and updates it after issuing the TABLEUPDATE() function.

STATUS

Microsoft has confirmed this to be a problem in the Microsoft products listed at the beginning of this article. We are researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.

MORE INFORMATION

Steps to Reproduce Problem

1. Create a program called Test.prg containing the following code:

   SET MULTILOCKS ON
   SET EXCLUSIVE OFF
   SET DEFAULT TO SYS(2004)+"Samples\Data"
   OPEN DATABASE Testdata
   USE Customer
   =CURSORSETPROP("Buffering",2)
   GO 5
   REPLACE maxordamt WITH mfunc()
   REPLACE maxordamt WITH mfunc()
   =TABLEUPDATE()
   =CURSORSETPROP("Buffering",1)

   FUNCTION mfunc
   ** Moves record from original position
   oldrec=IIF(EOF(),0,RECNO())
   GO 1
   tmp=maxordamt
   IF oldrec>0
      GO oldrec
   ENDIF
   RETURN tmp

2. Run the program. The error "Record is not locked" appears after

   encountering the second REPLACE command.

REFERENCES

For more information about the affect of SET EXCLUSIVE, please see the following article in the Microsoft Knowledge Base:

   ARTICLE-ID: Q125732
   TITLE     : Cursor Created by User or ODBC Has EXCLUSIVE Status

For more information about the affect of READ NOLOCK, please see the following article in the Microsoft Knowledge Base:

   ARTICLE-ID: Q131031
   TITLE     : READ NOLOCK Behavior in Visual FoxPro

KBCategory: kbprg kbbuglist KBSubcategory: FxprgGeneral vfoxwinbuglist3.00 buglist3.00b buglist5.00

Additional reference words: 5.00 3.00 3.00b kbvfp300 kbvfp500 kbvfp600

Keywords          : kbprg kbVFp kbVFp300bbug kbVFp500abug kbVFp500bug buglist3.00 FxprgGeneral kbbuglist
Version           : WINDOWS: 3.0,3.0b,5.0,5.0a,6.0
Platform          : WINDOWS
Issue type        : kbbug