Ticket #985 (new defect)
checking for whether CUPS is running is fragile
| Reported by: | kaduk | Owned by: | |
|---|---|---|---|
| Priority: | normal | Milestone: | Upstream Utopia |
| Component: | -- | Keywords: | |
| Cc: | Fixed in version: | ||
| Upstream bug: | LP:814908 |
Description
We've recently discovered that we need to check whether CUPS is running in a few places, e.g. when adding printers. The obvious way, using lpstat -r, is actually nontrivial since that command merely prints output, instead of returning a status value of success for running and failure for not-running.
Thus, we end up parsing its output, which is fragile to upstream changing that output.
It looks like we currently check for CUPS' status in:
config/cluster-cups-config/debian/postinst config/cluster-cups-config/debian/configure-athena-printers
but that's just a quick check of the past 300 transactions in source-commits.
We should (a) file an upstream bug that lpstat -r should return a usable status code, and (b) try to make our scripts robust to any changes upstream might decide to make.
Change History
comment:2 Changed 13 years ago by kaduk
also config/cupsys-config/debian/configure-athena-printers since r25317
comment:3 Changed 13 years ago by kaduk
Zephyr discussion of hpijs parsing lpstat output reminds us that we should probably be setting LC_ALL=C here, a bit reminiscent of #958
comment:4 Changed 13 years ago by kaduk
Got a reply to the launchpad bug:
Checking for presence of the file /var/run/cups/cupsd.pid to find out if
cups is running is more robust in my opinion.
Anyway if you think lpstat -r needs to return nonzero value if cups isn't
running this should be reported upstream to CUPS here:
http://www.cups.org/str.php
Please also add a link to the upstream str in this bug report.
** Changed in: cups (Ubuntu)
Importance: Undecided => Wishlist
** Changed in: cups (Ubuntu)
Status: New => Triaged
** Tags added: needs-upstream-report
