only if ~/.tcshrc not found

Newer versions of the Bourne Shell only

Available on systems that support the "User Portability Utilities option"; value of the variable must be an absolute path, and it is ignored "if the user's real and effective user IDs or real and effective group IDs are different."

$ENV is $HOME/.shrc in newer versions of the Bourne Shell

Same behavior as sh, but only if invoked as sh (bash 2+) or, since bash 4.2, also if invoked explicitly in POSIX compatibility mode (with options --posix or -o posix).

^ Only in sh/ksh compatibility mode (when invoked as bash, sh, ksh)

^ The first readable file in order of ~/.bash_profile, ~/.bash_login and ~/.profile; and only ~/.profile if invoked as sh or, as of at least Bash 4.2, if invoked explicitly in POSIX compatibility mode (with options --posix or -o posix)