Path: utzoo!attcan!uunet!nih-csl!lhc!adm!cmcl2!yale!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!pacific.mps.ohio-state.edu!davis From: davis@pacific.mps.ohio-state.edu ("John E. Davis") Newsgroups: comp.unix.questions Subject: Preventing Idle in telnet, security, and bg. Message-ID: Date: 28 Sep 90 05:58:09 GMT Sender: news@pacific.mps.ohio-state.edu Reply-To: davis@pacific.mps.ohio-state.edu (John E. Davis) Distribution: comp Organization: "Dept. of Physics, The Ohio State University" Lines: 39 Hi, I have a vt320 that I use all the time. When I logon to our system, I start up a process in the background that sleeps for a minute, checks my mailbox for newmail then just before going back to sleep, it sends the time and number of mail messages to my vt320 status line. It has worked fine so far with no problems. However, sometimes I forget to kill it before I logout. I was wondering what is the best way to put it into the background so that when I logout, it dies? I wrote the program in c, if this helps. A friend of mine once told me that when he logged on, it started writing to his terminal. Apparantly, I was once attached to that tty and left it executing when I logged out. I really do not understand this particular occurence at all. Perhaps some kind soul will tell me what happened. On another subject, One person on our system has in his home directory an executable file called 'ls'. Here it is: #! /bin/sh /bin/ls -FC echo `whoami` `hostname` `tty` `date` >> public/log exit 0 What happens, is if someone steps into this directory and types 'ls' this thing takes his picture. In principle, he could add a few more lines to copy and delete mail, etc... Although this 'ls' is harmless, it is conceivable that great damage could have been done. Is this considered a security problem? I do not advocate snooping around the system, however if one is new as I am to the unix world, then one can benifit by seeing what other people have. For example, by looking in other .emacs files, I learned alot of things about setting up the arrow keys for my terminal. Besides, isn't any file with world read access considered to be in the public domain? -- John bitnet: davis@ohstpy internet: davis@pacific.mps.ohio-state.edu