On 30/11/2014 02:01 AM, Jim Henderson wrote:
> On Sat, 29 Nov 2014 21:57:25 +0000, Orchid Win7 v1 wrote:
>
>> (It seems several processes received SIGINT, but for no defined reason
>> THEY CONTINUE RUNNING!>_<  I have no idea why.)
>
> Because signals can be captured, ignored, or their behaviours can be
> changed.  SIGINT is just a signal to a program, and writing an
> interceptor isn't that difficult. :)

But WHY are dd, cat, tee and md5sum ignoring this signal? They don't 
usually, and I can see the signal is definitely being delivered.

The Bash script is explicitly trapping SIGINT, but I can also see it 
receiving multiple SIGPIPE signals... Why doesn't that kill it?

Also, why does Bash keep cloning() itself? Is it to create subshells or 
something? (Obviously clone() followed by execve() is how it executes 
commands. But clone() on its own? Why?)

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On Sun, 30 Nov 2014 09:24:54 +0000, Orchid Win7 v1 wrote:

> On 30/11/2014 02:01 AM, Jim Henderson wrote:
>> On Sat, 29 Nov 2014 21:57:25 +0000, Orchid Win7 v1 wrote:
>>
>>> (It seems several processes received SIGINT, but for no defined reason
>>> THEY CONTINUE RUNNING!>_<  I have no idea why.)
>>
>> Because signals can be captured, ignored, or their behaviours can be
>> changed.  SIGINT is just a signal to a program, and writing an
>> interceptor isn't that difficult. :)
> 
> But WHY are dd, cat, tee and md5sum ignoring this signal? They don't
> usually, and I can see the signal is definitely being delivered.
> 
> The Bash script is explicitly trapping SIGINT, but I can also see it
> receiving multiple SIGPIPE signals... Why doesn't that kill it?
> 
> Also, why does Bash keep cloning() itself? Is it to create subshells or
> something? (Obviously clone() followed by execve() is how it executes
> commands. But clone() on its own? Why?)

Sounds like a bug, or worse.

Jim



-- 
"I learned long ago, never to wrestle with a pig. You get dirty, and 
besides, the pig likes it." - George Bernard Shaw

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