[Nut-upsuser] Tripp Lite OMNI1000 LCD issues

Arjen de Korte nut+users at de-korte.org
Sun Mar 30 08:14:03 UTC 2008

> The only reference to "/var/run/nut" in the strace is a
> chdir("/var/run/nut").

That's where the driver has just dropped priviledges (line 537 in
drivers/main.c) and just before it sets up the signals (line 540).

> Does it create the socket after this this chdir?

Yes, but *way* after that in dstate_init (line 562).

> What would the strace show upon executing the socket creation?

Unless you know what your looking for, strace isn't particularly useful.
We prefer debug output over strace most of the time, unless the debug
output is inconclusive. The debug output has the advantage that it shows
context in a meaningful way, at least for developers like me that deal
with this almost in a daily basis.

The call to 'dstate_init(progname, upsname)' will create a socket that is
named 'usbhid-ups-trippy', most likely in /var/run/nut, where you should
also see a PID file (line 573) named 'usbhid-ups-trippy.pid'. Again, make
sure that the user running the driver is allowed sufficient access to the
/var/run/nut directory. Setting the permissions bits right is just one way
that access might be limited. I don't know if Debian has something similar
like AppArmor for instance, which might prevent a process (rather than a
user) access to certain resources.

Best regards, Arjen
Eindhoven - The Netherlands
Key fingerprint - 66 4E 03 2C 9D B5 CB 9B  7A FE 7E C1 EE 88 BC 57

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