Adrian Irving-Beer wrote: > Now, if you really want to know if your script is being run by a > *user* rather than in the background (by a system script, cron, etc.), > then you can check the result of > > test -t 0 > or > [ -t 0 ] > > to determine if standard input is a terminal. That will give the wrong answer if input to the script ever comes from something that isn't a terminal, e.g. $ script <input $ script <input & $ sort input | script $ sort input | script & In all cases above, a real interactive user at a shell is calling the script; but, standard input is not a terminal and "-t 0" fails. -- -IAN! Ian! D. Allen Ottawa, Ontario, Canada - www.ottawa.ca EMail: idallen [ at ] idallen [ dot ] ca Home Page: http://www.idallen.com/ College professor (Linux) via: http://teaching.idallen.com/ Support free and open public digital rights: http://eff.org/