Bug#4107: emacs leaves stale lockfiles and publishes pathnames

[eichin@kitten.gen.ma.us (Mark W. Eichin)]

first of all, 19.29 is way old -- 19.31 is the current package, and
19.32 is imminent. 

Second, the lock file names *have* to be world visible, in order for
locking to actually work among users... hmm, your suggestion of a
one-way hash make sense, I'll pass it upstream and see if it goes
anywhere (xemacs has built in md5 support, but emacs19 doesn't.)
Oddly enough, if you don't have long filename support, emacs uses a
CRC to create a short-enough hash of the filename...

I guess they don't need to be world writable either -- world readable
would suffice (the files contain the pid, and that's needed to
determine if the ostensibly locking process is still around...)

If you have particular security concerns, you could also set
EMACSLOCKDIR in your environment (setting it to something nonexistent
should defeat locking altogether; not sure though. It *won't* fall
back to the compiled in value.)