DOS 3

[proteanthread]

Does anyone have any advanced programming info on Atari DOS 3? ML Calls, XIO, etc. ?

[Rybags]

Should be much the same as DOS 2.x

 

I don't think there's any set entry points for calls, no doubt there'd be undocumented "illegal" ones but using them is risky.

Of course like any DOS there's the JMP ($A) to enter the command processor/menu.

 

XIO (Special) functions should be same as 2.x - I don't know if there's any extra commands like Binary Load available.

 

The big difference is NOTE/POINT. DOS 3 uses relative pointers unlike 2.x which uses absolute sector.

 

 

Of course the big question is "Why bother with 3.0". Practically nobody uses it, you'd get much better functionality using SpartaDOS. Or if only using standard 90/130K disk sizes, DOS 2.5 does the job OK.

[thorfdbg]

XIO (Special) functions should be same as 2.x - I don't know if there's any extra commands like Binary Load available.

Almost. All the ones 2.xx supports are also supported by 3.0. However, there are a couple of extras. One of them is a binary load, the other one resolves wildcards, i.e. expands a wildcard into a full filename. It is mostly used internally by the DUP. Actually, Dos 2.++ (part of Os++) supports the 3.0 command set.

 

Another difference is the open mode #13 which, unlike #12, can also extend files beyond the EOF. It is also supported by 2.++ though not by 2.5 to my very knowledge.

 

 

The big difference is NOTE/POINT. DOS 3 uses relative pointers unlike 2.x which uses absolute sector.

Which makes 3.0 POINT/NOTE considerably more useful than the 2.xx counterpart.

 

So long,

Thomas