[Coco] Megaread problems

[Dave Philipsen]

Just a note.  I'm not sure if I found a bug in NitrOS9 'copy' or not. 
But just for snicks I tried something. I have an 8MB ramdisk named '/R0' 
and I have a 128MB SD card partition named '/SD0'. There is plenty of 
free space on '/SD0'.  So I tried as below to 'copy /R0@ 
/SD0/ramdisk-image'.  This should copy the entire ramdisk to an image 
file on the SD card.  The copy basically worked but it locked up the 
shell I was in even after the file was supposedly written (which 
shouldn't have taken much more than 30 seconds).  I hit 'BREAK' and 
finally regained the shell but the copy process was still running.  I 
killed it and 'procs' showed it was gone but the system was still being 
bogged down with something.  I had to re-boot NitrOS9 to clear it.  When 
I did a 'dir -e' of /SD0 I found the huge file in the directory and it 
was the correct size (80 0000) but its attributes were null (--------) 
and the owner was '8000'.  When I tried to delete the file I got a 214 
error so I used ded and found the first sector of the file and manually 
corrected the attributes and the owner so that when I did a 'dir' the 
owner showed as '0' and the attributes showed as '--ewrewr' ($3F) and 
then I was able to delete it. At first glance the filesystem on my SD 
card is ok but I have't checked it all thoroughly yet.  Maybe I just 
didn't allow enough time for the copy to finish.  Has anyone ever run 
into such a problem before?  Has anyone ever manipulated files as large 
as 8MB under NitrOS9?  I did create a file of slightly over 1MB in size 
and everything seemed to be ok.

I'm going to format another SD card and play around a bit and see if I 
can re-create the problem and find out exactly what it is.


Dave

On 3/27/2017 12:44 PM, Dave Philipsen wrote:
> I guess the problem has to do with the fact that the reference to 
> '/DD' is just a reference to the root directory.  If you use '/DD@' 
> then you will be referencing the raw device. Alternatively, you could 
> create a file that is at least as large as the desired megaread and us 
> it like this:  'megaread </dd/bigfile'.
>
> The error #214 is normal for trying to open/read a directory.  For 
> instance, try 'copy /dd mydir'.  You'll get the same error.  You 
> could, however, 'copy /DD@ mydir' in which case you'd need to make 
> sure that the device which will hold 'mydir' is larger than the 'DD' 
> device itself.
>
> Dave
>
>
> On 3/27/2017 7:35 AM, Robert Gault wrote:
>> Something very strange is going on with the version of megaread in 
>> the current NitrOS-9 builds. The program works correctly for Dave 
>> Philipsen and possibly everyone else. It fails for me on any system I 
>> try.
>>
>> megaread 1 </DD
>>
>> The above should run the program for the minimum number of reads with 
>> standard input changed to /DD. For MESS, VCC, and a 512K Coco3 the 
>> result is error #214.
>>
>> megaread </DD
>> Same error as above for the default 1024 repeats.
>>
>> The crc for the version under test is $A5A49C, size $7A which is 
>> identical with the nightly build version. Attr for tested drives 
>> indicates normal values.
>>
>> Robert
>>
>
>