How can I tell (in
~/.bashrc) if I'm running in interactive mode, or, say, executing a command over ssh. I want to avoid printing of ANSI escape sequences in
.bashrc if it's the latter.
PS1 is set and $- includes i if bash is interactive, allowing a shell script or a startup file to test this state.
So you can use:
if [[ $- == *i* ]] then do_interactive_stuff fi
When an interactive shell that is not a login shell is started, bash reads and executes commands from /etc/bash.bashrc and ~/.bashrc, if these files exist.
~/.bashrc is only sourced for interactive shells. Sometimes, people source it from
~/.profile which is incorrect since it interferes with the expected behavior. If you want to simplify maintenance of code that is common, you should use a separate file to contain the common code and source it independently from both rc files.
It's best if there's no output to stdout from login
rc files such as
~/.profile since it can interfere with the proper operation of
rsync for example.
In any case, it's still a good idea to test for interactivity since incorrect configuration may exist.
This is how red hat does it... Guessing it's the fastest way...
if [ "$-#*i" == "$-" ]; then
It means get the bash parameters, do a substring removal, shortest possible, match everything between the beginning and i. Then check if it's the same as the original bash parameters.
Check you did your job by connecting to the user using sftp, it will fail if non interactive sessions have output