As far as I know, the interactive shells may be login or not login, and the start up files for them are different.
- If interactive + login shell →
/etc/profilethen the first readable of~/.bash_profile,~/.bash_login, and~/.profile - If interactive + non-login shell →
/etc/bash.bashrcthen~/.bashrc
I want to set some variables every time I use an interactive shell regardless whether it is a login shell or not.