lenny@quincy.UUCP (Lenny Tropiano) (12/09/87)
On my UNIX PC I have noticed a problem occasionally with the
getlogin(3C) system call. At certain times I have noticed
getlogin returning "LOGIN" or "rc" instead of the user's name
who is logged in.
I know what "LOGIN" and "rc" are, but why are they showing up
for a valid logged-in user? This is quite strange...
--- piece of code ---
char *getlogin();
printf("User is: %s\n", getlogin());
--- end piece of code ---
Any suggestions? I have recreated the /etc/utmp, /etc/wtmp and
this hasn't cleared up the problem. Sometimes it goes away
and other times it comes back.
Thanks,
Lenny
--
Lenny Tropiano UUCP: ...uunet!godfre!quincy!lenny -or-
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Islandia, New York 11722 +1 516-582-5525 ...ihnp4!icus!quincy!lennyignatz@chinet.UUCP (Dave Ihnat) (12/12/87)
Yep; I've seen this one, when I was porting 'mdm'. I'll bet you're running more than one shell login window. It seems that getlogin() isn't quite swift enough to differentiate between the physical device--probably 'console'--and the virtual windows 'w1', 'w2', etc. on that device; so it'll return whatever it finds first in /etc/utmp. I haven't spent the time yet to yank the object out of the library, rewrite it, stuff it back in the library, etc. Not to mention having to muddle around in the shared library... -- Dave Ihnat ihnp4!homebru!ignatz || ihnp4!chinet!ignatz (w) (312) 882-4673
lenny@icus.UUCP (Lenny Tropiano) (08/15/88)
In article <578@proxftl.UUCP> aaron@proxftl.UUCP (Aaron Zimmerman) writes: |>I have a curious problem on my 3b1... |> ... |>$ who am i |>aaron w4 Aug 12 08:01 |>$ passwd |>Changing password for LOGIN |>Permission denied. ... The problem occurs not in passwd (or the /etc/passwd file), but in the getlogin(3C) function call. This problem occurs if you use multiple getty's on /dev/window, or you have something running on w1 when the getty respawns for /dev/window. The following example with show this: lenny + w1 Aug 14 20:05 . 4428 root + w4 Aug 14 21:51 . 5623 (Note: I'm logged in with two gettys, the current one is w4). # tty /dev/w4 # passwd Changing password for lenny New password: [...] getlogin(3C) looks up the /dev/window login finding the first entry in /etc/utmp it finds. I maybe logged in on w4 as root, but getlogin thinks I am logged in as lenny on w1. In your case with user LOGIN, it found was a LOGIN_PROCESS. (A "getty" process waiting for login) Something like: LOGIN + window Aug 14 21:54 . 5880 root + w4 Aug 14 21:51 . 5623 Those are the disadvantages in running multiple gettys, although having the capability to login more than once is nice. (Something I'm working into the window-manager I am rewriting). -Lenny -- Paper-net: Lenny Tropiano | @-net: lenny@icus.UUCP ICUS Software Systems | !-net: ...sbcs \ PO Box 1 | boulder \ Islip Terrace, NY 11752 | talcott !icus!lenny Vocal-net: (516) 582-5525 [work] | pacbell / (516) 968-8576 [home] | hombre / Telex-net: 154232428 ICUS | Another-net: attmail!icus!lenny
woods@gpu.utcs.toronto.edu (Greg Woods) (08/16/88)
In article <467@icus.UUCP> lenny@icus.UUCP (Lenny Tropiano) writes: >In article <578@proxftl.UUCP> aaron@proxftl.UUCP (Aaron Zimmerman) writes: >|>I have a curious problem on my 3b1... >|> >... >|>$ who am i >|>aaron w4 Aug 12 08:01 >|>$ passwd >|>Changing password for LOGIN >|>Permission denied. >... > >The problem occurs not in passwd (or the /etc/passwd file), but in the >getlogin(3C) function call. This problem occurs if you use multiple >getty's on /dev/window, or you have something running on w1 when the >getty respawns for /dev/window. I've also had this problem with 386/ix, when a getty in the LOGIN state dies abnormally. A 'who -a' shows LOGIN and xyzzy both on the port, but it gives an exit status for LOGIN. I'd call this a bug (and I will bug-report it too). The problem occurs with any utility that calls getlogin(3C), including mail, etc. -- Greg Woods. UUCP: utgpu!woods, utgpu!{ontmoh, ontmoh!ixpierre}!woods VOICE: (416) 242-7572 [h] LOCATION: Toronto, Ontario, Canada