qb45qck.hlp (Table of Contents; Topic list)
Important Notice
The pages on this site contain documentation for very old MS-DOS software, purely for historical purposes. If you're looking for up-to-date documentation, particularly for programming, you should not rely on the information found here, as it will be woefully out of date.
LOCK...UNLOCK Statement QuickSCREEN
  QuickSCREEN      Details      Example      Contents      Index
──────────────────────────────────────────────────────────────────────────────
LOCK...UNLOCK - file I/O statements that control access by other
                processes to all or part of an opened file
 
Tip: LOCK and UNLOCK are only useful in network environments where
     several processes may need access to the same file, and only
     function if you are using DOS version 3.1 or later.
 
Syntax
  LOCK [#]filenumber [,{record |[start] TO end}]
  [statements]
  UNLOCK [#]filenumber [,{record | [start] TO end}]
 
    ■ filenumber is the number of an open file
    ■ record, start, and end indicate the range of records or bytes to
      be locked