su's man page:
For backward compatibility, su defaults to not change the current directory and to only set the environment variables HOME and SHELL (plus USER and LOGNAME if the target user is not root). It is recommended to always use the --login option (instead of its shortcut -) to avoid side effects caused by mixing environments. ... -, -l, --login Start the shell as a login shell with an environment similar to a real login: o clears all the environment variables except TERM o initializes the environment variables HOME, SHELL, USER, LOGNAME, and PATH o changes to the target user's home directory o sets argv of the shell to '-' in order to make the shell a login shell
It's hard to tell if there's any difference between
--login (or supposedly just
-l). Namely, the man page says "instead of its shortcut -", but all these options are grouped together, and I don't see an explanation of the difference, if it exists at all.
UPD I checked the question, which is supposed to solve my problem. The question is basically about difference between
su -. And I'm asking about difference between
su - and
su --login. So no, it doesn't solve it at all.