Command-line arguments from DOS XL/SDX

[dmlloyd]

Does anyone know of a reference which explains how command-line arguments are passed to ".COM" style XEXes in DOS XL (and presumably SDX as well)? I'm given to understand that both DOSes use a similar mechanism but I can't seem to find any information about how to write an XEX that accepts arguments. I'm near to disassembling .COMs at this point.

[Sikor]

DOS XL: http://atariki.krap.pl/index.php/DOS_XL

Sparta Dos X: http://sdx.atari8.info/index.php?show=en_docs

[atari8warez]

Does anyone know of a reference which explains how command-line arguments are passed to ".COM" style XEXes in DOS XL (and presumably SDX as well)? I'm given to understand that both DOSes use a similar mechanism but I can't seem to find any information about how to write an XEX that accepts arguments. I'm near to disassembling .COMs at this point.

 

SDX:

 

SpartaDOS User Accessible Data Table

 

Several SpartaDOS variables have been made available to programmers

to allow easy access to the command line for applications and utilities.

This data table is referred to as COMTAB and is pointed to by the OS vari -

able DOSVEC at memory location 10 ($0A). An assembly language example

is included for aid. This table is valid with all versions of Sparta-

DOS except where noted. Locations COMTAB, ZCRNAME, BUFOFF, COMFNAM,

and LBUF are also supported by OS/A+ and DOS XL.

 

 

ZCRNAME COMTAB+3

This is a 6502 jump instruction followed by the address of the file name

crunch routine. This location is used to interpret the command line. A

jump here will pull the next command from LBUF, translate the drive or

device identifier if one is given (i.e., A: to D1:), add the default drive iden-

tifier if none is given and place the result at COMFNAM. Each call will advance

BUFOFF to point to the next entry on the command line, so that

each call to the crunch routine will get the next entry on the line. If no

entries remain, the 6502 zero flag will be SET on return. Since the 6502

has no indirect jsr, it is necessary to use a few lines of code to access this

routine.

 

 

COMFNAM COMTAB+33

This is the destination buffer for the ZCRNAME routine. It will ALWAYS begin

with a Dd: since the default drive is added if none is given. If you are

looking for switches or other options, start looking at COMFNAM+3. This

buffer is 28 bytes long.

 

LBUF COMTAB+63

This is the input buffer for the command processor. The entire command

line is stored here. LBUF is 64 bytes long.

Edited April 11, 2012 by atari8warez