[Interest] Interest Digest, Vol 79, Issue 20

Roland Hughes roland at logikalsolutions.com
Thu Apr 26 14:38:24 CEST 2018

On 04/26/2018 03:44 AM, Thiago Macieira wrote:
> On Wednesday, 25 April 2018 06:53:26 PDT Roland Hughes wrote:
>> What I'm trying to tell you is there was and still is a legitimate
>> reason to have a QDataStream which can write big-endian. Don't just rip
>> it out. Make it some kind of settable boolean flag in the class. There
>> is no way to know just how many of these things are still out there and
>> are still being developed. Most were in the world of defense
>> contractor/military
> I never claimed it isn't. In fact, there is a flag to set the endianness.
> When I said "most machines are little-endian", I was referring to machines Qt
> runs on and, therefore, would use QDataStream. The fact that the default is
> big endian is short-sighted. It should default to little-endian.
No. Taking a disposable chip's view of the world is short sighted and 
completely invalidates the historical reason for the class. It was 
created to feed real computers which operate in Big-Endian.

Read up on seismic testing or stuff happening with the Super Colliding 
Super Conductor. In the case of SCSC many thousands of disposable chip 
"sensors" running an application to pick up one or a few certain 
readings are streaming that stuff back to the only box which can handle 
them, big iron. IBM was never the fastest computationally, but when it 
comes to data throughput to/from disk they are a 14" city water main and 
their nearest competitor is happy the one day per week they achieve 
being a fire hose.

Here's a delightful little book about oil well drilling. I've read mine 
many times.

In today's world "Big Oil" uses satellites to identify "potential" 
places with oil reserves. For anything above water they then go through 
the long, arduous journey of getting permits to do seismic testing. Such 
testing involves drilling thousands of shot-holes (depending on the size 
of the potential reserve). Some have actual shots put in them with a 
blast sensor built using a disposable chip behind them to 
control/ensure/measure the blast. (Dry fires happen and the test 
analysis software has to be made aware of it.) A large percentage of 
these sensors will simply be lost, hence the need for disposable chips. 
They used to use Z-80, then for years INTEL x86 was the ultimate throw 
away chip. Now it is moving to ARM since you can get a Raspberry Pi for 
$15 or less when bought in 100 quantities.

Don't assume the class was created for use within the world of the 
disposable chip.

That particular class was designed so Qt on disposable chips could 
provide real computers an actual service.

Oh, here's a wee bit to add.

No company or person is allowed to _own_ seismic data. There is an 
industry standard format where binary data is big-endian. Upon request, 
for a nominal media and shipping fee, if you have it you have to provide 
it to whoever asks. Geologically and environmentally, we don't want 100+ 
companies drilling 1000+ shot-holes in the exact same county. What you 
are allowed to own is the analysis software you develop.

Do NOT change the default behavior of that class. It wasn't written for 
use on an iDiot Phone. It's design was and still is far reaching. Had it 
not existed, Qt would have had a dramatically shorter growth arc, 
possibly not surviving long enough to make it onto iDiot Phones. 
Changing the default behavior of the class would be viciously short sighted.

Sorry, I don't mean to sound insulting, but, in this particular case you 
are a grain of sand on the beach trying to remove the ocean because it 
gets you wet.

Roland Hughes, President
Logikal Solutions


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