My first DontZap use case while testing F11 beta

[Peter Hutterer]

On Fri, Apr 17, 2009 at 11:29:02PM +0200, Lars E. Pettersson wrote:
> On 04/17/2009 10:32 PM, Anders Rayner-Karlsson wrote:
>> * Lars E. Pettersson <lars at homer.se> [20090417 21:37]:
>>> How often does people actually accidentally press ctrl-alt-backspace? 
>>> I  have *never* done it.
>>
>> By same argument, taking a rather tongue in cheek attitude, how often
>> does countries with nuclear ICBM's launch them by accident?
>
> It is not argument as such. If the decision has been made to remove this  
> functionality, the decision has to be based on something. In this case  
> it seem to be based on that people accidentally can press this  
> key-stroke combination and loose data. If this is the case, it is  
> important to know how often this actually happens.
>
> If you look at real life. In our kitchens we have knifes. You can  
> accidentally injure yourself quite badly with a knife. Should we just  
> because of this zap all knife blades to make them safe?

no, but most people keep them in a knife block and not in the same drawer as
ladles, stirring spoons and whatnot.

> I.e. we have made a decision that knifes are good to have, accidents do  
> happen, but the benefit from having knifes are greater than the  
> consequences of the accidents that can happen. So we keep our knifes.

and by moving the kives to a separate place we may have saved a few fingers
over the history.

Also, it's important here that we're not talking about the butter knives where
you can't hurt yourself unless you swallow them as a three-year old (like
VT-switching, easy to recover). we're talking about the really sharp cooking
knives, the onces where you don't know you cut yourself until you hear the
scraping on the bone.

also, I think this knife analogy is stretching things a bit, but I like
cooking (and it beats debugging grabs anytime), so we can continue :)

> This analogy converted to this discussion says that OK some, a few, may  
> accidentally press ctrl-alt-backspace, but at the same time this  
> particular key-stroke is very handy under those circumstances when X  
> behaves badly. By removing the functionality you also adds another cost,  
> the cost of extra data loss and other problems, i.e. with file systems,  
> as user, when ctrl-alt-backspace does not work, finally will press the  
> reset button or power cycle their computer. As I see it the benefit from  
> having ctrl-alt-backspace is greater than the cost of a few loosing data.
>
> I.e. how often this problem happens, people accidentally pressing  
> ctrl-alt-backspace, is a valid question in this discussion. Does it  
> happen more often than X crashes? Or less? This is an important  
> parameter in the decision to keep, or not keep, the functionality.
>
>> While you certainly can present an argument based on that you have
>> _never_ done this by accident, I'd like to point you at
>> http://en.wikipedia.org/wiki/Argument_from_ignorance for reasons why
>> this is, IMHO, not a sustainable platform to argue from.
>
> Sigh! I just mentioned that *I* had never accidentally pressed this key  
> combination during all those years that I have been using Linux, and  
> therefore find it strange that this has become such a big issue that  
> some wants to remove this functionality. It was *NOT* ment to be a  
> platform to argue from, such an argument would be plainly stupid. If I  
> during all my years have never accidentally pressed this combination,  
> how often does it happen to others? I.e. for me X crashes have happened  
> way more often then me accidentally pressing ctrl-alt-backspace. How is  
> it for others?

fwiw, about once a week or so for me (I have a lot of shortcuts on ctrl+alt).

btw, it's quite interesting to look at the key press/release events as you're
typing you'll notice that often you're typing multiple letter before releasing
the first.

Cheers,
  Peter