I followed Rust tutorial to install Rust on my Arch Linux, and found the Rust directory is indeed added into ~/.profile file:

$ cat ~/.profile

export PATH="$HOME/.cargo/bin:$PATH"

But after re-login, I couldn’t see Rust folder is in $PATH variable:

$ echo $PATH
/usr/local/sbin:/usr/local/bin:/usr/bin:/opt/cuda/bin:/usr/lib/jvm/default/bin:/usr/bin/site_perl:/usr/bin/vendor_perl:/usr/bin/core_perl

It didn’t take effect!

After reading Arch Linux Bash document, I noticed the following statement which describes ~/.bash_profile:

If this file does not exist, ~/.bash_login and ~/.profile are checked in that order.

So this means that if ~/.bash_profile exists,~/.bash_login and ~/.profile won’t be checked, right? Let’s do a check:

(1) Use strace command to record the files’ names related to current user when logining.

$ strace -o out -e open bash -l
$ grep "/home/xiaonan" out
open("/home/xiaonan/.bash_profile", O_RDONLY) = 3
open("/home/xiaonan/.bashrc", O_RDONLY) = 3
open("/home/xiaonan/.bash_history", O_RDONLY) = 3
open("/home/xiaonan/.bash_history", O_RDONLY) = 3
$ exit
logout

As expected, the ~/.profile, i.e., /home/xiaonan/.profile wasn’t opened.

(2) Renamed ~/.bash_profile to pretend it didn’t exist, checked whether ~/.profile would be read:

$ mv .bash_profile .bash_profile.bak
$ strace -o out -e open bash -l
$ grep "/home/xiaonan" out
open("/home/xiaonan/.bash_profile", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/home/xiaonan/.bash_login", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/home/xiaonan/.profile", O_RDONLY) = 3
open("/home/xiaonan/.bash_history", O_RDONLY) = 3
open("/home/xiaonan/.bash_history", O_RDONLY) = 3
$ echo $PATH
/home/xiaonan/.cargo/bin:/usr/local/sbin:/usr/local/bin:/usr/bin:/opt/cuda/bin:/usr/lib/jvm/default/bin:/usr/bin/site_perl:/usr/bin/vendor_perl:/usr/bin/core_perl
$ exit
logout

As things turned out, when the ~/.bash_profile didn’t exist:

open("/home/xiaonan/.bash_profile", O_RDONLY) = -1 ENOENT (No such file or directory)

The bash would access ~/.bash_login and ~/.profile in sequence, and $HOME/.cargo/bin was added into $PATH finally.

The solution of this issue is adding following statement in ~/.bash_profile:

[[ -f ~/.profile ]] && . ~/.profile

Now it works!