UNLOCK
 Release file/record locks set by the current user
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 Syntax

     UNLOCK [ALL]

 Arguments

     ALL releases all current locks in all work areas.  If not specified,
     only the lock in the current work area is released.

 Description

     UNLOCK is a network command that releases file or record locks set by
     the current user.  Use it when you want to release the current lock
     without setting a new lock.  Both FLOCK() and RLOCK() release the
     current lock before setting a new one.

     After an UNLOCK, an update to a shared database file and associated
     index and memo files becomes visible to DOS and other applications, but
     is not guaranteed to appear on disk until you perform a COMMIT or close
     the file.

     Refer to the "Network Programming" chapter in the Programming and
     Utilities Guide for more information on the principles of locking and
     update visibility.

 Notes

     .  SET RELATION: UNLOCK does not automatically release a record
        lock along a RELATION chain unless you UNLOCK ALL.

 Examples

     .  This example attempts an update operation that requires a
        record lock.  If the RLOCK() is successful, the record is updated
        with a user-defined function and the RLOCK() is released with UNLOCK:

        USE Sales INDEX Salesman SHARED NEW
        IF RLOCK()
           UpdateRecord()
           UNLOCK
        ELSE
           ? "Record update failed"
           BREAK
        ENDIF

 Files   Library is CLIPPER.LIB.