If you define the logical FAL$LOG to a byte hex value, then FAL will
write some debugging information about the net-process to the
log-file.

  bit 0 - filenames and type of access
  bit 1 - performance statistics
  bit 2 - DAP messages
  bit 3 - DAP message packet and mailbox AST completion
  bit 4 - DAP message packet and mailbox QIO requests
  bit 5 - internal counters

In addition qualifiers can be specified:

  /DISABLE=<2 hex digit>         bit 0 - disable DAP CRC check
                                 bit 1 - disable DAP message blocking
                                 bit 2 - disable RMS multiblock caching
                                 bit 3 - disable manual routing
  /ENABLE=<2 hex digit>
  /BPM=<5 decimal digit>         max. number of bytes/DAP message to display
                                 (default: 20)
  /BPL=<2 decimal digit>         max. number of bytes/line to display
                                 (default: 20)
  /RBK_CACHE=<3 decimal digits>  RMS multiblock cache size
                                 (default: 64, range:1-127)
  /DBS=<5 decimal digit>         DAP buffer size
  /SYSTEM_ID=<4 hex digit>       system identification
                                 (<FILESYS><OSTYPE>)
  /VERSION=<8 hex digit>         DAP version number
                                 (<DECVER><USRNUM><ECONUM><VERNUM>)
  /SC1=<8 hex digit>             system capabilities part 1
                                 (bit 31-0 of <SYSCAP>)
  /SC2=<8 hex digit>             system capabilities part 2
                                 (bit 63-32 of <SYSCAP>)