So, you want to cd into /var/foo but it gives you a permission denied error and when you want to use
sudo to do this you are not permitted.
What is the technical reason for this and is it possible to do this some other way?
The reason you can’t do this is simple,
cd is not a program but an in-built command and
sudo only applies to programs.
sudo foo means run the program foo as root so it’s not possible to use
But luckily there is a workaround for that:
You can use
sudo -i to elevate yourself to super user. Like that:
istechnolgy@localhost:~$ sudo -i
istechnolgy@localhost:~$ cd /var/foo
But be careful, this can be dangerous, now you are logged on as root and as root you can use whatever commands you wish without any restriction. It is very very important that after you finish whatever you had to do in that folder to logout as root, this is also simple, just type
exit and you are back to being logged on as a normal user.