Maytag repairman moving from TCSH to BASH. [OPEN]

[gentsquash]

Tho' still a rank beginner, I have become a Gentoo enthusiast.
It seems that more Gentooers use BASH than TCSH, so I have
decided to switch. I have skimmed the BASH man-page, but would
still appreciate any as-explicit-as-possible answers to the
following beginner's questions.

Q1: What is a/the proper mantra to put in a to-be-sourced script
that says

"If the calling shell is non-interactive, then exit this script".



Q2: Is there a global place to put bash aliases/functions that
will be read in for all users (or all non-root users) for ALL
interactive shells? (whether or not it is a login-shell)

o It seems that "/etc/profile" is only read by login-shells.

o If possible, I'd like a global solution. In particular, I
don't want to assume that users even HAVE a "~/.bash_profile" file.


Q2': For interactive, but non--login shells, WHERE is the prompt
PS1 set? Is that a script where it is reasonable to have a
global-place-for-aliases script sourced?


https://forums.gentoo.org/viewtopic.php?p=1911426#1911426
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