Q188064: PRB: ISRLOCKED() and ISFLOCKED() Return Incorrect Values

Article: Q188064
Product(s): Microsoft FoxPro
Version(s): WINDOWS:5.0,5.0a
Operating System(s): 
Keyword(s): 
Last Modified: 11-DEC-1999

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, versions 5.0, 5.0a 
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SYMPTOMS
========

When an instance of Visual FoxPro locks a record or a table, calling the
ISRLOCKED() or ISFLOCKED() functions on another computer or another instance of
Visual FoxPro returns false.

RESOLUTION
==========

Test the lock status using RLOCK() or FLOCK() instead. ISRLOCKED() and
ISFLOCKED() only indicate whether the record or file is locked by the instance
of Visual FoxPro from which they are called. If these functions were to test for
the record and file locks of other users, the lock status could quickly change.
This would make the information returned by ISRLOCKED() and ISFLOCKED
unreliable.

STATUS
======

This behavior is by design.

MORE INFORMATION
================

Steps to Reproduce Behavior
---------------------------

1. Save the following code in a program and run the program:

        *-- Code begins here.
        CREATE TABLE locktest (field1 C(10))
        CLOSE DATA
        USE locktest SHARED
        INSERT INTO locktest (field1) VALUES ("A test")
        GOTO 1
        =RLOCK()
        *-- Code ends here.

2. On another computer or in another instance of Visual FoxPro, save the
  following code in a program and run the program:

        *-- Code begins here.
        USE locktest SHARED
        GOTO 1
        IF ISRLOCKED()
            WAIT WINDOW "Record is locked."
        ELSE
            WAIT WINDOW "Record is not locked."
            =RLOCK() && Should get the "Attempting to lock..." in status bar
        ENDIF
        *-- Code ends here.

  If you run the program from another computer, please map a drive to the first
  computer containing the Locktest table.

After you run the second program the Wait Window appears. Press any key and the
"Attempting to lock..." message appears in the status bar.

REFERENCES
==========

(c) Microsoft Corporation 1998, All Rights Reserved.
Contributions by Mike Stewart, Microsoft Corporation


Additional query words: kbDSupport kbDSE vfoxwin

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Keywords          :  
Technology        : kbVFPsearch kbAudDeveloper kbVFP500 kbVFP500a
Version           : WINDOWS:5.0,5.0a
Issue type        : kbprb

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