Command line documentation and command line to give permission

Hi,

I have been looking around but could not find any good, comprehensive documentation for all the command line command on ESXi 5.1? Does it exists? Where?

A side question, is there a command line command that I can use to change the permissions on an ESXi 5.1 server? (like the permission tab on vSphere Cli)

Thank in advance,

Olivier