Yrurtj

In any Bourne-style shell, the i option indicates whether the shell is interactive:

case $- in

  *i*) echo "This shell is interactive";;

  *) echo "This is a script";;

esac

There's no portable and fully reliable way to test for a login shell. Ksh and zsh add l to $-. Bash sets the login_shell option, which you can query with shopt -q login_shell. Portably, test whether $0 starts with a -: shells normally know that they're login shells because the caller added a - prefix to argument zero (normally the name or path of the executable). This fails to detect shell-specific ways of invoking a login shell (e.g. ash -l).

fish shell

Here's the answer for fish in case any other users stumble upon this page.

if status --is-interactive

    # ...

end



if status --is-login

    # ...

end



echo "darn, I really wanted to have to use globs or at least a case statement"

Fish documentation: initialization

csh / tcsh

For csh and tcsh I have the following in my .cshrc file:

if($?prompt) then               # Only interactive shells set $prompt

    ...

endif

Specifically for tcsh, the variable loginsh is set for a login shell:

if($?loginsh) then              # A login shell..

    ...

endif

(tcsh also has a variable shlvl which is set to the number of nested shells, where the login shell has a value of 1.)

Another way is to check the result of tty

if [ "`tty`" != "not a tty" ]; then

UNIX/Linux has a command to check if you are on a terminal.

if tty -s

then

echo Terminal

else

echo Not on a terminal

fi

You can check to see if stdin is a terminal:

if [ -t 0 ]

then

    echo "Hit enter"

    read ans

fi

Take a look at the shopt command (at least for Bash).
That can definitely tell you if you're in a login shell. I don't know about interactive/batch.

Reference: http://www.linuxquestions.org/questions/programming-9/how-to-check-in-a-script-whether-the-shell-is-login-or-non-login-360629/

Look in the Bash man page for more info: http://linux.die.net/man/1/bash

Note: I am giving you Bash, since that's what I know. Presumably other shells have similar functionality.

To check whether a script runs in an interactive or non-interactive shell,
I check in my scripts for the presence of a prompt stored in the $PS1 variable:

if [ -z $PS1 ] # no prompt?

### if [ -v PS1 ]   # On Bash 4.2+ ...

then

  # non-interactive

  ...

else

  # interactive

  ...

fi

This I learned here: https://www.tldp.org/LDP/abs/html/intandnonint.html

i is not the correct option to look for. -i is to force an otherwise
non-interactive shell to become interactive. The correct auto-enabled
option is -s, but Bash unfortunately does not handle this correctly.

You need to check whether $- contains s (this is granted to be
auto-activated) or whether it contains i (this is not granted to
be auto-activated but officially only coupled to the -i command line
option of the shell).