trb (07/22/82)
The following comments apply at least to UNIX as distributed by UCB, I haven't bothered to check the other 31 flavors. Whilst searching for >>> the answer <<< this morning, I came upon the following interesting tidbits: /usr/bin/spell uses the following six one-letter environment variables: B D F H S V One of my users was complaining that spell didn't work. Turns out that he committed the heinous crime of setenving S to a string of his personal choosing. (You're talking heinous, here.) The spell diagnostic was: spell: cannot initialize hash table. (Thanks.) How about distributing programs which use more imaginative variable names, or at least don't depend on the fact that an innocent user won't have his own one letter variable names. Tidbit #2: I decided that it would be nice to be able to put comment entries into a /usr/lib/uucp/L.sys file. So in I goes into the uucp source and I find that someone has already been nice enough to hack uuname so that if the first three letters of a system name are "xxx" then the entry would not be printed by uuname, and the "xxxfoo" would not match any system except one named xxxfoo, so that's ok. There was no signature on the lower right hand corner of that delectable morsel of UNIX trivia either. I can't imagine what seized whoever-it-was to have an initial xxx be the standard comment character for L.sys, but there you are. Ever twiddling, for you hacking pleasure, Andy Tannenbaum Bell Labs Whippany, NJ (201) 386-6491