Re: bashrc question

[Greg Wooledge <greg@wooledge.org>]

On Thu, Dec 26, 2024 at 04:16:17 +0100, henrik@privatembox.com wrote:
> Hello
> 
> I have these settings in .bashrc of my home dir:
> 
> $ cat .bashrc
> export TF_CPP_MIN_LOG_LEVEL=3
> export CUDA_VISIBLE_DEVICES=-1
> 
> but every time after i login the system, the settings are not activated.
> I have to source it by hand to make it work.
> 
> what's wrong with me?

1) What shell do you use?
2) How do you get to a terminal?

If you're not using bash as your login shell, then it makes perfect
sense .bashrc wouldn't be read.

If you open a terminal which works *normally*, it should run a non-login
shell, which in the case of bash should read .bashrc.

However, if your terminal has been configured to run a login shell,
then it will read .bash_profile or .bash_login or .profile instead.

However however, your .profile or equivalent should be configured to
dot in your .bashrc file, possibly after verifying that you are, in
fact, in bash.

A .profile which fails to dot in .bashrc will lead you to all kinds of
subtle problems whenever you launch a login shell, which would normally
be when you ssh in, or login on a text console.

A terminal emulator should normally run a NON-login shell, but some of
them are sometimes configured to do the wrong thing because it works
around stupid users.  So, if you're using a Desktop Environment that
assumes you are a stupid user, it might be running your shell as a login
shell.

You can tell whether your shell is a login shell by looking at the
name it's invoked with (via ps(1) or similar commands).  If the
invocation name begins with a hyphen ("-"), it's a login shell.


hobbit:~$ ssh localhost
greg@localhost's password: 
Linux hobbit 6.1.0-28-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.1.119-1 (2024-11-22) x86_64
[...]
hobbit:~$ ps -fp $$
UID          PID    PPID  C STIME TTY          TIME CMD
greg     1001894 1001893  0 22:46 pts/29   00:00:00 -bash


That's a login shell, because I ssh'ed in.  You can tell because it's
invoked as "-bash" instead of "bash".  As a login shell, it will read
my .profile, and my .profile contains:


hobbit:~$ grep bashrc .profile
. ./.bashrc


so that my .bashrc file is *also* read.  Yours should have this too,
or something fancier, maybe even

    test "$BASH" && source ~/.bashrc

or the default Debian /etc/skel/.profile way:

    # if running bash
    if [ -n "$BASH_VERSION" ]; then
	# include .bashrc if it exists
	if [ -f "$HOME/.bashrc" ]; then
	    . "$HOME/.bashrc"
	fi
    fi

which is ridiculously verbose.  I went with a more basic route.