/* $DOC$
   $TEMPLATE$
      Function
   $NAME$
      hb_FLock()
   $CATEGORY$
      API
   $SUBCATEGORY$
      FileSys
   $ONELINER$
      Locks part or all of any file
   $SYNTAX$
      hb_FLock( <nHandle>, <nOffset>, <nBytes> [, <nType ] )
                --> lSuccess
   $ARGUMENTS$
      <nHandle>  OS file handle

      set>  Offset of the first byte of the region to be locked.

      <nBytes>   Number of bytes to be locked.

      e>    The type (read or write) of lock requested.
   $RETURNS$
      <lSuccess> .T. if the lock was obtained, else .F.
   $DESCRIPTION$
      This function attempts to lock a region of the file whose file handle
      is <nHandle>. This is a low-level file function.  To lock Harbour
      data files use either the FLock() or RLock() function.

      The value of <nHandle> is obtained from either a call to the FOpen()
      or the FCreate() function.

      <nOffset> is the offset (from the beginning of the file) to the first
      of the region to be locked.  (Offsets from the current position
      nd of file are not currently supported.)

      <nBytes> is the length of the region to be locked in bytes.

      <nType> is the type of lock requested.  There are two types of locks:
      exclusive write locks ( <nType> = 0x0000 ) - the default, and shared
      read locks ( <nType> = 0x0100 ).  Additionally you can specify a
      blocking version of this function (that is it won't return until
      either an error has occurred or the lock has been obtained) by
      adding 0x0200 to the above values.
   $EXAMPLES$
      // refer to tests/tflock.prg
   $STATUS$
      R
   $COMPLIANCE$
      H
   $PLATFORMS$
      All
   $FILES$
      Library is core
   $SEEALSO$
      hb_FUnlock(), FOpen(), FCreate(), FError(), FClose()
   $END$
 */

/* $DOC$
   $TEMPLATE$
      Function
   $NAME$
      hb_FUnlock()
   $CATEGORY$
      API
   $SUBCATEGORY$
      FileSys
   $ONELINER$
      Unlocks part or all of any file
   $SYNTAX$
      hb_FUnlock( <nHandle>, <nOffset>, <nBytes> ) --> lSuccess
   $ARGUMENTS$
      <nHandle>  OS file handle

      set>  Offset of the first byte of the region to be locked.

      <nBytes>   Number of bytes to be locked.
   $RETURNS$
      <lSuccess> .T. if the lock was removed, else .F.
   $DESCRIPTION$
      This function attempts to unlock a region of the file whose file
      handle is <nHandle>. This is a low-level file function.  To
      unlock Harbour data files use the dbUnlock() function.

      The value of <nHandle> is obtained from either a call to the FOpen()
      or the FCreate() function.

      <nOffset> is the offset (from the beginning of the file) to the first
      of the region to be unlocked.  (Offsets from the current position
      nd of file are not currently supported.)

      <nBytes> is the length of the region to be unlocked in bytes.
   $EXAMPLES$
      // refer to tests/tflock.prg
   $STATUS$
      R
   $COMPLIANCE$
      H
   $PLATFORMS$
      All
   $FILES$
      Library is core
   $SEEALSO$
      hb_FLock(), FOpen(), FCreate(), FError(), FClose()
   $END$
 */