upgrading python on raspbian

[Gene Heskett]

On Sunday 13 October 2019 16:22:33 Chris Angelico wrote:

> On Mon, Oct 14, 2019 at 6:38 AM Gene Heskett <gheskett at shentel.net> 
wrote:
> > I'm not a python expert by a long ways.
> >
> > I have built the linuxcnc-master, which is the development branch of
> > linuxcnc, a machine control program to run most metal carving
> > machines. Lathes, milling machines, anything you can motorize,
> > LinuxCNC can run.
> >
> > This requires a preempt-rt kernel which I've managed to build and
> > install, all on a pi-4b running raspbian buster, the armfh-v7l
> > version of debian 10.1.
> >
> > But linuxcnc is quite elderly code, some of it going back to before
> > there was a linux, so despite being actively developed right now for
> > x86 type hardware but has quite a list of missing dependencies I
> > cannot satisfy from the raspbian repos.
> >
> > They are:
> >
> > The following packages have unmet dependencies:
> >  linuxcnc-uspace : Depends: python2.7-glade2 but it is not
> > installable or
> >
> > Can anyone supply a list of python3 packages that will cover the
> > functions contained in the above list?, and I will attempt to edit
> > the linuxcnc srcs to use the more modern code base?
>
> So if I understand you correctly, you're not worried about actually
> supplying these apt packages, but you want equivalents so you can port
> the code itself to Py3?

I think thats the obvious path forward. Once ported, we don't have to 
worry about that legacy stuff for two or 3 generations of linux. I have 
it building on raspbian buster-10.1 for a rpi4b right now in "uspace" 
mode, but missing stuff has cost us a couple of the pretty gui-faces we 
use with it, and I'd like to find a way around that if I could.

> My recommendation would be to start with "sudo apt build-dep
> linuxcnc-uspace" and see if it can get any, but otherwise, just
> replace "python-" with "python3-" and see if that works. You may need
> to dig up dev packages of them though.

The 2 packages that are missing right now are python-gtksourceview2, and 
python-vte.  Do they have python3 equ's? Finding python3 replacements 
for those 2 would take some pressure off its forward march.

as far as build dep detection, dpkg-checkbuilddeps is as dumb as a rock. 
I've had to add at least ten packages now to get it to build, that were 
never detected by dpkg-checkbuilddeps. And its major stuff, like 
inkscape and imagemagick. checkbuilddeps is ok before a 1st build, 
finding 50 or so things it needed, but for major stuff, a waste of time 
after the first session.

> Another option may be to just use pip to install your dependencies.
> That might work out easier.

There seems to be an underground effort to throw pip and pip3 under the 
bus of late. I'm wonder why?

Thanks ChrisA.

Cheers, Gene Heskett
-- 
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