Trying to install EMC2 on Ubuntu 11.04 Natty Narwh

Nothing about EMC2 run on Ubuntu 11.04?

Thanks

I faced only one problem - emc2 depends on python 2.6, but in ubuntu 11.04 default packet for the python is 2.7.

The worst thing that both 2.7 and 2.6 are installed in the system!

I think that main problem is in python package. "Python" - is the meta package that used to install and run default python for the system. So in ubuntu 11.04 it points to python-2.7, and emc2 needs python (<=2.6). Probably there's possibility to change the source to make it depend on "python2.6" instead of "python (<=2.6)"...

Does any body know why emc2 cannot work with python2.7??? And if it is a unsolvable problem may be there's a way to change "python" calls to "python2.6" in the source codes???

Hi

No idea why EMC will not run with python 2.7, if you run configure from the sources, you will see if it is set to python <=2.6 as you suggest, which sounds likely

If you want to use 2.6 instead there are 2 possible strategies.

First is simply to go into Synaptic Package manager, highlight python v 2.7 installed and from Package > Properties > Version
downgrade the package to 2.6

I have had to do this several times for packages like ncurses, as EMC builds from scratch need a particular version of readline which depends on a lower version of ncurses than the default for Ubuntu 10.4
(unfortunately Arduino relies on the higher version, so I have to keep shuffling back and fro)

If you are not offered 2.6 as an option, you will need to add the Lucid Lynx repositories under Settings > Repositories

The second is simply to edit the /usr/bin/python symlink to point to python2.6 instead of python2.7, if you have both on your system.

All the python files I have seen start with #!/usr/bin/python or #!/usr/local/bin/python to tell bash what interpreter to use and don't specify a version number, that is what the symlink is for.

regards

Main problem that emc2 has dependency of python 2.6 so it wont install until apt will see python 2.6 in python package. So hack with simlink wont work.

If i try to downgrade to python2.6, i.e. installing python meta package from Lucid, apt says me that about 180 packet depends on python 2.7 and they will have to be removed, so it's not a solution ether.

I was wondering is there any way to install packet using apt despite it's dependencies?
I'm using 11.04 on my home pc with hobby cnc router, so I'll not be to upset if something accidentally goes wrong while machining.

Hi

I thought you were saying that EMC would not run without python 2.6,

...quote...both 2.7 and 2.6 are installed in the system!

and that you already had 2.6, not that you could not install the deb package of emc2.

The problem is not the package, it is only a .tar.gz of the binaries and you could copy its contents across manually if you wanted, completely bypassing apt.
You will find it here:- www.linuxcnc.org/emc2/dists/lucid/emc2.4/

What it does not give you is the rtai kernel, all the kernel modules etc.
You would have to copy that over from 10.4 CD distro and sort any dependencies, run grub, depmod etc etc. or compile it yourself.

I used to compile lots of custom kernels some time back, when distros did not properly support the emerging hardware, so it is all possible if you are willing to spend the time and effort.

The big question is, what is so special about Ubuntu 11.04?

I did not even know it had been released, because I don't upgrade unless I need the new capabilities and am sure it will not impact on the rest of my system.

Unfortunately I think John is right, best way forward would be to re-install 10.4 from CD or even better install it on a separate partition and then you can have EMC and bleeding edge Ubuntu booted on the same box

regards

ArcEye wrote:

Hi
...
What it does not give you is the rtai kernel, all the kernel modules etc.
You would have to copy that over from 10.4 CD distro and sort any dependencies, run grub, depmod etc etc. or compile it yourself.
...
The big question is, what is so special about Ubuntu 11.04?
...
Unfortunately I think John is right, best way forward would be to re-install 10.4 from CD or even better install it on a separate partition and then you can have EMC and bleeding edge Ubuntu booted on the same box

regards

I compiled RTAI kernel once in 2007, and I can not say that it was to easy. It was great practice to make emc2 installable in one console command!

...

11.04 has some new drivers so it can work properly with new hardware. I use emc2 once a week and it's not to comfortable to make another partition and have another system for that. I've used emc2 with ubuntu 10.10 without having any problems. So it will be really great to be able using it with 11.04.
Some users on cnc-club.ru reported that they are having some hardware problems with 10.04.

And finally we have to look forward to new LTS version it will have python >= 2.7 as meta python package for sure . It's not pointless to fix this problem now.

quote......11.04 has some new drivers so it can work properly with new hardware.

What drivers are you looking at and are they built in to the kernel or separate modules?

It's a wet day here and I am having a play with 11.04 with a view to either compiling a new rtai kernel or making the 10.04 one work.

If it is a module, should be able to compile it for existing kernel

Just a thought

PS Having installed 11.04, I am horrified by the default interface, with its attempts to mimic a smart phone or touch pad screen layout.
I won't be using it, would take far too long to change it over to the the fast stripped down interface I use, for no benefit to me.
Still interested in what the new drivers are though to have a look at them.

Hi take a look here...

Go on then - spill the beans!

Nick wrote:

I faced only one problem - emc2 depends on python 2.6, but in ubuntu 11.04 default packet for the python is 2.7.

I have since compiled a working rtai kernel on 11.04
I think it was using python-old-doctools suggested by apt solved python dependency issues for emc.

My main issue was the availability of magma patches for later kernels and the fact that the kernels in the 2.6.37+ range appear to have changed their hardware detection to a method that is unable to recognise my trusty Acer monitor which has been PnP in everything since I bought it.
Having to struggle manually inserting xorg.conf with resolutions above 1024x768 for a Ubuntu version I had no actual need for, rather halted my interest in it.

regards