PYTHONPATH variable blank

问题

According to documentation, sys.path is initialized from PYTHONPATH when python session starts. However, in my case, PYTHONPATH variable is empty. When I execute this in terminal:

echo $PYTHONPATH

it returns blank. On the other hand, when I start python and inspect sys.path:

import sys
print (sys.path)

I get back a long list of paths. Where do those get loaded from? What am I missing?

回答1:

Check the documentation again:

It says

[sys.path is initialized] from the environment variable PYTHONPATH, plus an installation-dependent default.

And furthermore,

the first item of this list, path[0], is the directory containing the script that was used to invoke the Python interpreter [… or] the empty string

That’s why yours isn’t empty.

来源：https://stackoverflow.com/questions/48599467/pythonpath-variable-blank