UNLOCK Statement

 Action

 Releases locks applied to parts of a file.

 Syntax


  UNLOCK #  filenumber% , { record& |  start&  TO  end&}


 Remarks

 The  UNLOCK statement is used only after a  LOCK statement. See the entry
 for the  LOCK statement for a complete discussion.

 The  UNLOCK statement uses the following arguments.

-----------------------------------------------------------------------------
 Argument                                Description
 ----------------------------------------------------------------------------
  filenumber%                            The number used in the  OPEN
                                         statement to open the file.

  record&                                The number of the record or byte
                                         to be locked. The argument
                                         record& can be any number between
                                         1 and 2,147,483,647 (equivalent to
                                         231 -1), inclusive. A record can
                                         be up to 32,767 bytes in length.

  start&                                 The number of the first record or
                                         byte to be locked.

  end&                                   The number of the last record or
                                         byte to be locked..





 For binary-mode files,  record&,  start&, and  end& represent the number of
 a byte relative to the beginning of the file. The first byte in a file is
 byte 1.

 For random-access files,  record&,  start&, and  end& represent the number
 of a record relative to the beginning of the file. The first record is
 record 1.

 Warning

 Be sure to remove all locks with an  UNLOCK statement before closing a file
 or terminating your program. Failing to remove locks produces unpredictable
 results.

 The arguments to  LOCK and  UNLOCK must match exactly.

 Do not use  LOCK and  UNLOCK on devices or ISAM tables.

 See Also

  LOCK... UNLOCK

 Example

 See the  LOCK... UNLOCK statement programming example, which uses the
 UNLOCK statement.