I've always just used 'mail.' Why doesn't this work any more?

Berkeley mail

/usr/bin/mail, /usr/ucb/mail

is from an older, less mobile era of email use. Today's email user demands flexible access to their email, from a variety of sources, including the Unix shell, a client like Thunderbird, Evolution, Mac Mail, or Outlook on their desktop, via the web with a Gmail-like interface, or through mobile devices like tablets and smart phones.

The solution for this type of flexibility is with the IMAP protocol. IMAP allows for remote access to mail spools, with the ability to store and organize mail on the user's mail server.

'mail' expects mail to be held on the system that the user types the 'mail' command on, and in the environment now at PCN, the mail server is an entire system devoted to nothing but the handling of sending, recieving, and presenting mail to users, not one for general purpose use, like 'bohr'. Without direct access to mail, the mail command simply does not work.

'mail' can still be used, though for quick sending of messages, just not for reading. (Commands like “mail staff@physics.purdue.edu < helpme.txt” will work just fine.)