I have the Tex Live 2017 in Trisquel, I installed from the compact disc.
I need to update the tkz-euclide package, for that I entered the tlmgr window:
When I order the update, I get this result:
Executing action update tkz-euclide
tlmgr: package repository /usr/local/texlive/2017 (not verified: unknown)
tlmgr: saving backups to /usr/local/texlive/2017/tlpkg/backups
tlmgr: no updates available
tlmgr: Your installation is set up to look on the disk for updates.
To install from the Internet for this one time only, run:
tlmgr -repository http://mirror.ctan.org/systems/texlive/tlnet ACTION ARG...
where ACTION is install, update, etc.; see tlmgr -help if needed.
To change the default for all future updates, run:
tlmgr option repository http://mirror.ctan.org/systems/texlive/tlnet
Completed.
When I execute that command in my shell, I get this message:
tlmgr: no action given; try --help if you need it.
I do not know what else to do.