Command line arguments can be passed to main()
after BLOAD. Since this is not
supported by BASIC, the following syntax was chosen:
]CALL2051:REM ARG1 " ARG2 IS QUOTED" ARG3 "" ARG5
main
is the program name.The runtime for the Apple ][ uses routines marked as
.INTERRUPTOR
for ProDOS 8 interrupt handlers. Such routines must be
written as simple machine language subroutines and will be called
automatically by the interrupt handler code when they are linked into a
program. See the discussion of the .CONDES
feature in the
assembler manual.
The function
dio_open() has the single
parameter device
to identify the device to be opened. Therefore an
Apple II slot and drive pair is mapped to that device
according
to the formula
device = slot + (drive - 1) * 8
so that for example slot 6 drive 2 is mapped to device
14.
The function
dio_query_sectcount() returns
the correct sector count for all ProDOS 8 disks. However for any non-ProDOS 8
disk it simply always returns 280 (which is only correct for a 140 KB disk).
This condition is indicated by the _oserror
value 82.