However, to determine whether the foundations I have laid are solid enough, I feel somewhat compelled to address them.
A mailbox was simply a file with a particular name. It’s only special property was its protection which only allowed other users to append to the file. That is, they could write more material onto the end of the mailbox, but they couldn’t read or overwrite what was already there. The idea occurred to me that CPYNET could append material to a mailbox file just as readily as SNDMSG could. SNDMSG could easily incorporate the code from CPYNET and direct messages through a network connection to remote mailboxes in addition to appending messages to local mailbox files.
And yet, that it may be determined whether the foundations that I have laid are sufficiently secure, I find myself in a measure constrained to advert to them.