/usr/spool/mail

[utzoo!decvax!ucbvax!unix-wizards]

>From menlo70!hao!pag at Berkeley Tue Sep  8 12:09:30 1981
In addition to security problems inherent in having /usr/spool/mail
writeable, the mail mechanism of removing mailboxes also proved annoying
in the following respect.  If someone wanted to protect their mailbox
from reading (chmod 0600 ), it would last only as long as the mailbox,
ie, not too long!  We made a few minor changes that leave mailboxes
zero length -- then access bits have meaning.