HP 3000 Manuals

User Logging Programmer's Guide

Building a DISC Logfile 

If the logfile to be used will reside on disc, use the :BUILD command to
create the logfile and specify ;CODE=LOG. Ensure the file is large enough
to contain one day's data.  All other defaults in the :BUILD command may
be used for file attributes.  Refer to the :BUILD command in the MPE XL 
Commands Reference Manual (32650-90003).

MPE/iX 5.0 Documentation