The TPU$FILEIO routine handles all DECTPU file operations.
    Your own file I/O routine can call this routine to perform some
    operations for it. However, the routine that opens the file must
    perform all operations for that file. For example, if TPU$FILEIO
    opens the file, it must also close it.

    Format

      TPU$FILEIO  code ,stream ,data

  Additional Information (explode) :

• Returns
• Arguments
• Description
• Condition Values Returned