There was also a feature Mike Lesk added that allowed a marked line, something like %! command to cause the command to be executed when the recipient read the mail, for example to demonstrate a feature of a program or teach the recipient something. He meant well. Dennis had the closest he ever had to a conniption, and it was taken out post haste. Meaning well is not enough. -rob On Mon, Jul 31, 2023 at 4:23 AM Norman Wilson wrote: > Doug McIlroy: > > This reminds me of how I agonized over Mike Lesk's refusal to remove > remote execution from uucp. > > ==== > > Uux, the remote-execution mechanism I remember from uucp, had > rather better utility than the famous Sendmail back-door: it > was how uucp carried mail, by sending a file to be handed to > mailer on the remote system. It was clearly dangerous if > the remote site accepted any command, but as shipped in V7 > only a short list of remote commands was allowed: mail rmail > lpr opr fsend fget. (As uucp was used to carry other things > like netnews, the list was later extended by individual sites, > and eventually moved to a file so reconfiguration needn't > recapitulate compilation). > > Not the safest of mechanisms, but at least in V7 it had a use > other than Mike fixing your system for you. > > Is there some additional history here? e.g. was the list of > permitted commands added after arguments about safety, or > some magic command that let Mike in removed? Or was there a > different remote-execution back door I don't remember and don't > see in a quick look at uuxqt.c? > > Norman Wilson > Toronto ON >