Please see the command below:
david_lee@david-desktop:/home/david_lee/test$ sudo ln -s test /usr/bin/test
david_lee@david-desktop:/home/david_lee/test $ test
bash: /usr/bin/test: Too many levels of symbolic links
That is to say i got the error: Too many levels of symbolic links.
The reason is that, when I creating the symbolic link, I only used the relative path, but not the absolute path.
The solution is to use the absolute path.
david_lee@david-desktop:/home/david_lee/test$ sudo ln -s /home/david_lee/test/test /usr/bin/test