achoi@cory.Berkeley.EDU (CHOI ANDREW MAN-TAT) (09/14/90)
Hello world. This is my first posting to this newsgroup, please accept my apology in advance if I have inadvertently violated any netiquette. I have the following 2 questions about command 'ps' and 'wall': 1) How does 'ps' work? Where does it get the information about all the processes running on the system? I suspect it may have something to do with /dev/kmem (Kernel Memory); however, since I don't have read/write permission on /dev/kmem, how can 'ps' acquire the permission to read /dev/kmem? Is there a setuid program exec by 'ps' to get root access? 2) Even after I do 'mesg n' or 'chmod og-rx /dev/tty?', other users can still send me message through command 'wall', how come? Is there anyway to prevent 'wall' from sending the message? Thank you very much for your time and effort in answering these questions. Name: Andrew Choi Internet Address: achoi@cory.berkeley.edu Phone: (415)848-5658 Address: 2605 Durant Ave., Berkeley, CA 94704 #include <std/disclaimer.h>