BLOBROOTUNLOCK()
 Release the lock on a BLOB file's root area
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 Syntax

     BLOBROOTUNLOCK() --> NIL

 Description

     Use BLOBROOTUNLOCK() to release a lock previously obtained using
     BLOBROOTLOCK().

     By default, this function operates on the currently selected work area.
     It can be made to operate on an unselected work area by specifying it
     within an aliased expression.

     Note:  The only functions that require the use of BLOBROOTLOCK() or
     BLOBROOTUNLOCK() are BLOBROOTGET() and BLOBROOTPUT().

 Examples

     .  This example illustrates how to properly lock and unlock the
        root area of a BLOB file for a database file opened in shared mode:

        FUNCTION GETSETTINGS()
           LOCAL aCustSettings

           // Open a customer file in shared mode
           USE customer NEW SHARED VIA DBFCDX

           IF BLOBROOTLOCK()
              aCustSettings := BLOBROOTGET()
              BLOBROOTUNLOCK()
           ELSE
              Alert("Could not obtain root lock of Customer;
                 file")
           ENDIF

           CLOSE

           RETURN aCustSettings