S_DW

 Function
  Set the share deny write flag in a FCREATE/FOPEN/FAPPEND statement.

 Value
  2 = 10b = 2o = 2h

 Remarks
  DOS 3.1 or later (which is what is required by PCBoard) allows processes
  to decide what mode of file sharing should be allowed.  This constant
  allows you to specify that other processes may open the same file, but
  that they may not open it for write access, from the time you open the
  file to the time you close the file. This is useful when you want to
  ensure that data will not change while you are reading it.

 Example

  FOPEN 1,"FILE.DAT",O_RD,S_DW ' Deny other processes write access
  FOR i = 1 TO 10
   FGET 1,s
   PRINTLN s
  NEXT
  FCLOSE 1 ' Close the file and allow others to open it in any mode