On Tue, Oct 23, 2018 at 03:20:12PM +0000, Chen, Farrah wrote: > But in Bash script, it cannot work, it keeps its original value: > [root@fchen ~]# cat test.sh > #!/usr/bin/bash > echo $PS4 > echo $FAN
This is because you're doing it as root. Bash strips PS4 from the environment when started as root, as a security precaution. wooledg:~$ PS4='hello' bash -c 'set -x; true' hellotrue wooledg:~$ sudo env PS4='hello' bash -c 'set -x; true' [sudo] password for wooledg: + true Notice how it works as expected as a regular user, then "fails" under sudo.
