[Coco] NitrOS9 question

[Neal Crook]

That sounds completely reasonable. Memory is allocated based on the module
header declaration.. there's not really any way (or reason) to look inside
the module and determine whether its content is valid/reasonable  (and no
need for you to zero-out the unused space). In fact you  probably need not
change the size of the bootfile blob at all.. just the header declaration
for the last module. Caveat: assuming you have crc checking turned off (as
it is by default)

Neal

On 7 Oct 2017 10:52, "Dave Philipsen" <dave at davebiz.com> wrote:

> Ok, I compiled a minimum headless OS9Boot file that should boot with a
> shell on T2 as my terminal.  The size of the bootfile is $42F8. When I try
> to boot with it, as expected,  it fails.  I get the banner text from Init
> and Sysgo.  Interestingly, sometimes when it boots I also get a string
> printed to the screen that says, "WHAT?"
>
> Now I use dEd and simply <D>iddle the file length to $4401 and manually
> clear out the extra data to all zeroes. Voila! NitrOS9 boots and I get the
> shell prompt on my terminal!  If I diddle it one byte shorter to $4400 it
> will not boot.  So it apparently matters only that the length of the file
> is $4401 or longer.
>
> Another interesting point:  If I diddle the file length of OS9Boot even
> greater to $8000 it still boots but smap reports way less system memory.
> So that tells me that the system memory allocation is based upon the size
> of the OS9Boot file, not its actual contents. Apparently no check is made
> to the contents of the file or whether it contains 'non-modulized' data!
>
> Dave
>
>
> On 10/7/2017 2:48 AM, Neal Crook wrote:
>
>> My guess is that it will make no difference. If it does, experiment 2 is
>> to
>> pad with 0xff. I await the result with interest.
>>
>> Neal.
>>
>> On 7 Oct 2017 08:04, "Dave Philipsen" <dave at davebiz.com> wrote:
>>
>> That would be an interesting experiment. I’ll see if I can try that this
>>> weekend.
>>>
>>> Dave
>>>
>>> On Oct 6, 2017, at 11:12 PM, Barry Nelson <barry.nelson at amobiledevice.
>>>>
>>> com> wrote:
>>>
>>>> What happens if you just pad the end of the OS9Boot file with zeros?
>>>>
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