dd dies on SIGUSR1

[David Schultz]

On Wed, Mar 23, 2011, Eitan Adler wrote:
> > We are talking about a design decision taken decades ago, which quite
> > possibly was a mistake.
> 
> Historical reasons are not be discounted, but in this case because the
> behavior is already non-portable, and already not be relied upon, so
> there is no reason that changing the default is harmful.
> 
> > Again, how many people rely on USR1 to terminate a process?
> 
> Hopefully none. Even if there are people who do rely on such behavior
> that reliance could be said to be a mistake or otherwise broken.

Please see my previous message.  The historical behavior of SIGUSR1
terminating a process by default is standard, even on Linux.

I believe one of the original uses of the signal was to allow
daemons and their children to signal each other.  In this use
case, if the notification can't be delivered because the recipient
is unprepared to accept it, termination is appropriate for a
fail-fast design.