mah@uhccux.uhcc.Hawaii.Edu (Michael Hoffhines) (07/12/90)
I have finally gotten MacLayers up and running on our Ultr*x box, thanks to many who directed me to the special version at Rascal, and find it to be great. It sure saves time being able to download files and still carry on with real work. On to my question: The documents state that I should be able to receive talk requests (while mesg is y, of course) to the login scirpt. This doesn't work. Requestors get the 'not accepting..' message and if I try to 'talk' to myself, I get the message 'You do not exist.' Much to my surprise. Anyone have any suggestions? While on the subject of MacLayers, here are two things I would like to see included in the future: ZMODEM and uploading support. Thanks in advance, Mike. >---------------------------------------------------------------------------< > Michael Hoffhines | INTERNET: mah@uhccux.uhcc.Hawaii.Edu < > ICS Department | < > University of Hawaii | Hey, hey, hey. Don't be mean. B. Banzai < >---------------------------------------------------------------------------<
bruner@sp15.csrd.uiuc.edu (John Bruner) (07/12/90)
Your inability to use "talk" probably is caused by a non-writable "/etc/utmp" file on your Ultrix system. This file, used by programs such as "who" and "w", records the current users on the system. It normally is written by "login" when you log in and cleared by a system daemon (either "init" for devices directly attached to the machine or the rlogin/telnet daemon for network connections). Many Unix machines do not allow write access to this file because of the confusion that it could cause. If MacLayers (or UW, or xterm, etc.) can't write "/etc/utmp", then you won't appear in a "who" listing and "talk" can't find you. If I recall correctly, MacLayers is cognizant of the responsibilities of running setuid or setgid. Therefore, it is possible to make the "/etc/utmp" file group writable for some owner/group "foo" and make MacLayers setuid/setgid-foo. That is a subject which you must discuss with your system administrator. You may also have discovered that you can't change your message permission with "mesg". The reason for this is related -- you don't own the pseudo terminal (MacLayers can't change the owner to you); therefore, the chmod() call in the "mesg" program will fail. I don't know if MacLayers has the code to do this. It would require making it setuid-root. It might appear that you can work around this by running "login" in the window; however, *don't do it*. It will write the "/etc/utmp" entry and will change the owner of the pseudo-terminal to you, but when the shell terminates nothing will clean it up. This will make it appear that you are still logged in, and the pseudo-terminal will be unusable by anyone else.