My user is already in 'wheel' group of CentOS and the 'ping' command doesn't work:
ping: socket: Operation not permitted
A guide here about using 'chmod +s' for 'ping':
https://github.com/MichaIng/DietPi/issues/1012#issuecomment-532840857
However, I saw another command 'chmod g+s', how does it differ from 'chmod +s'?
chmod +s sets both the UID and GID bits, while chmod g+s sets only the GID bit (and chmod u+ssets only the UID).
UID and GID bit lets the program run as the owner and/or the owner's group - rather than as the user and group of who actually started it. For example, a program may always run as if it had been started by root.
Lets say you have a file with ownership root:adm... chmod g+swould give the program access to some logs (bad?)... chmod +s would in addition let the program run with full root privileges (much much worse!).
