eric@umbc3.UMD.EDU (eric messick) (10/27/86)
Ultrix V1.2, Vax 11/785. This is a wierd one. I'm running csh as my default shell, but in my .login, I execute tcsh (the doc says something about Paul Placeway at OSU as the most recent modifier of tcsh), so I've got tcsh running under csh. I'm not certain that this makes a difference, but it seems possible/likely. I'm doing all of this nonsence because tcsh isn't a legal shell on our system, and isn't likely to be in the near future. Anyway, this combination doesn't graciously respond to HUP's. Impolitely disconnecting often seems to leave both the csh and the tcsh running, although whatever program was running at the time seems to die properly (usually). The natural response to this is to kill -9 the offending csh. Now, this is when something truely intersting happens. Suppose I was signed on to ttyS1 when I got rudely interrupted. Signing on again (to ttyS2), I might find: pid tty command 1111 S1 -csh (csh) 1112 S1 -csh (tcsh) 5000 S2 -csh (csh) 5001 S2 -csh (tcsh) at which point I would: kill -9 1111 right? At this point, our terminal server impolitely informs me that the vax requested that the connection be terminated. I.e. it logged ME off of S2!. Signing back on, I find that I'm on ttyS1, and: pid tty command 5000 S2 -csh (csh) 5001 S2 -csh (tcsh) 5010 S1 -csh (csh) 5011 S1 -csh (tcsh) so, I'm in EXACTLY the same position I was in before! ARRRRGGGGGG! The workaround? At this point, do a: kill -9 5000 5010 which seems to work, but impolitely logs me off anyway. What I want to know, is: How the HE*L did kill send that signal to a process that was related to the only one it had been told to signal only by being owned by the same user? Is that even what happened? Could it be in our terminal server software (it does other flaky things too) instead? Maybe the signal is getting to the right process (it does seem to be dieing, whereas the process that is getting hung up on doesn't), but the tty driver is hanging up the wrong port. Again: How the HE*L is it associating the two? This has happened enough to get me annoyed... Any ideas out there? -eric messick -- #include <standard/disclamer.h> #define SILLY_QUOTE I've lost my harmonica, Albert.... #define ARPA_ADDRESS eric@umbc3 [.umd.edu | .arpa] #define USENET_ADDRESS seismo!umcp-cs!cvl!umd5!umbc3!eric