qck.hlp (Table of Contents; Topic list)
Important Notice
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LOCK, UNLOCK Statements
  Summary  Details  Example                Contents  Index  Back
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 Controls access by other processes to all or part of an opened file:
    • Limits or prevents access (LOCK)
    • Releases any locks (UNLOCK)
 
    LOCK [#]filenumber% [,{record& | [start&] TO end&}]
    .
    .
    .
    UNLOCK [#]filenumber% [,{record& | [start&] TO end&}]
 
    ■ filenumber%        Number of an open file
 
    ■ record&            Any record number in the range 1 to
                         2,147,483,647, inclusive
 
    ■ start&             Number of the first record or byte to lock or
                         unlock
 
    ■ end&               Number of the last record or byte to lock or
                         unlock
 
 See Also
    File I/O Commands