DOC Avoiding to install as root on Linux

The first line of the installation docs says,

Meson is available in the Python Package Index and can be installed with sudo pip3 install meson which requires root

Installing packages as root from PyPi is practice that’s very much frowned upon, and the solution is often to use virtualenvs rather that using sudo. Sources:

• The Python Packaging Guide

  Due to the way most Linux distributions are handling the Python 3 migration, Linux users using the system Python without creating a virtual environment first should replace the python command in this tutorial with python3 and the python -m pip command with python3 -m pip --user. Do not run any of the commands in this tutorial with sudo: if you get a permissions error, come back to the section on creating virtual environments, set one up, and then continue with the tutorial as written.

• Various most voted Stack Overflow posts: https://stackoverflow.com/a/21056000/1791279, https://stackoverflow.com/questions/15028648/is-it-acceptable-and-safe-to-run-pip-install-under-sudo

It’s more or less arbitrary code execution as root. So IMO it might be better not to have this as the recommended installation option for unaware users.

In addition from that sentence it’s not clear if it’s only sudo that requires root (and user is free to install it as non root in a virtualenv) or if meson install additionally does something that requires root, and it needs to be installed as root in any case. This question is answered a few paragraphs below but still.

I can make a PR to improve the documentation if useful.

[eli-schwartz]

“install it” can be read as “install Meson” or “install Python 3”. I hope it’s the former, because that’s much better practice than sudo pip install. But the sentence after it makes it look like it’s “install Python 3”.

It was certainly intended to be the former. I hadn’t thought before now of it being interpreted as the latter.

[rth]

the install docs continue on to say “Only use a user copy of Meson if you do not care about installing projects as root.”

Yes, it does indeed, but at the very end. Most users probably never get there (I didn’t at first), they just run the command they encounter in the first sentence. I’ll open a PR to see if the formulation could be improved a bit to avoid this confusion.