The Basis System - Weapons and Complex Integration - Lawrence ...

call ptext(msg)
which is to write messages on graphics frames, if desired. The user-supplied ptext is responsible
for frame advances, etc.
72.4 Replaceable Routines
There are some routines which you can replace with your own versions. You merely need to be
sure that the binary for your routine is encountered first in the load process.
72.4.1 User main routine
Basis calls a subroutine usrmain immediately after collecting command line arguments. If you
need to do special initialization or to process the command line yourself, provide your own version
of usrmain. Normal basis error recovery procedures are not yet installed at this point. The
default usrmain calls basmain; your replacement needs to do that too. Any remaining text in
cmdline is treated as the first line of input by basmain.
subroutine usrmain(argv0, cmdline)
character*(*) argv0,cmdline
call basmain(argv0,cmdline)
return
end
72.4.2 Custom handling of input
Each line read from an input file is made available to a user-replaceable routine called basisech.
The default version (see below) does nothing.
subroutine basisech(line,nline)
character*(*) line
integer nline
return
end
72.4.3 Error handling
When Basis encounters an error in its input, it normally calls a routine named kaboom, to reinitialize
the parser and restore data structures to a clean state if possible. During error recovery, it
calls a user-replaceable routine named basiserr, which, by default, does nothing:
72.4. Replaceable Routines 417