Thank you. You raise a good point: It's not a bug. The functionality is
restored by reverting the python sym-link to its previous state,
i.e., pointing at python2 , as per the comments and advice from
Leonidas S. Barbosa
My only remaining (minor) complaint is that I can no longer develop
Python code using the command python to reference the latest version;
I have to specify the version in the invocation.
Generally speaking, I believe that if an application — especially a
critical system utility — depends on a particular version of a
general-use program that is known to be evolving and liable to change,
then that dependency is better kept encapsulated to that application.
The default version of such a general-use program should be allowed to
"float" and keep up with new developments, without risking damage to the
system by doing so.
In particular, if the Updater depends on python2 , but invokes it as
python , then this puts unnecessary and possibly harmful constraints on
the entire system: For instance, suppose another application or utility
comes along that depends on python3 but invokes it as python on the
assumption that python is linked to python3 ; the resulting conflict
will be difficult to resolve. This is not an unlikely scenario.
I think an argument can be made that the fact that the Updater and the
other utilities involved carry the assumption that python will always
be linked to python2 does constitute a bug of sorts. This bug would be
fairly easy to resolve, by changing its invocation(s) of python to
explicitly specify python2 and not depending on the system's default to
be frozen, especially to an obsolescent version.
I think it should be filed as a bug, but I don't believe I have
sufficient visibility into the internals of the utilities involved to
have authority to do so.
In the meantime, for my own purposes, I am going to create a link to
always-the-latest version of python and call it "rutnoy". Perhaps you
can guess why... ;-}
Regards,
------------------------------------------------------------------------
On 03/08/2018 12:12 PM, Dmitry Shachnev wrote:
> If you change important system paths (like /usr/bin/python), then you
> should be aware that this can cause damage on your system. This is not a
> bug.
>
> ** Changed in: twisted (Ubuntu)
> Status: New => Invalid
>
------------------------------------------------------------------------
--
David
[email protected] <mailto:[email protected]>
--
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/1754311
Title:
package python-twisted-core 16.0.0-1 failed to install/upgrade:
subprocess new pre-removal script returned error exit status 1
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/twisted/+bug/1754311/+subscriptions
--
ubuntu-bugs mailing list
[email protected]
https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
