[SOLVED]3 linxcnc-dev folder and installation

I feel a little stupid, but the last time I did it was with JA13 .... I find myself having 3 installations of Lcnc run in place on the same PC ... if I cancel 2 everything works great, but if I leave the old ones it gives me error as if it could not find Linuxcnc ... I guess it's because only one of the 3 installations is complete with linuxcnc the others have something overwritten, or I have to give a command to go from one folder to another, only that I don't know or remember.

can anyone suggest me the way?

regards

Finally I've find what I need. I use clonezilla for reply my cnc disk. In the second disk I install a new version of Lcnc. So when attach old dick I can use old version, and when new disk new version. Yes I've 3 disk, one for version.

After a while I remembered having done so in the past. Strange seemed to be able to switch between versions with a command ... but thinking that there can only be one instance of Lcnc per pc ... I think there is no other way.

regards

These is very stranges .... I've install disk2 (cloned one) and istall a new version in the folder linuxcnc-dev2 ... now I can work with old version (2.8) and new one (2.9). Obviusly not at same moment .... but in the original disk these is impossible .... At this point I think that something has been installed incorrectly on the old disk ... uff .... I'm getting old, it's true ... but it offends me to be able to prove that memory does not abandon me.

You can have many run in place installations and simply choose between them by running the rip-environment script in the
~/linuxcnc-devnn/scripts folder for the version you want to run.

Or to keep configs separate create a user for each version you have.....
eg user-27, user-28, user29 and log in as each user and build a run in place version.

No need for rebooting, no messing with configs between each version.Just need to stop the current running linuxcnc version and log out then log back in.