The indicated error in the jockey-<frontend> seems to be caused by jockey-backend script not finishing it's initialization stage, thus doesn't respond to frontend requests.
The jockey-backend script appears to be hanging in jockey.detection._get_printers(), while waiting on cups.Connection().getDevices(). In fact, the cupsd process goes to 100% CPU usage ocasionally and needs restart, so the real problem is probably in the cups/cups-client and jockey fails as a side-effect.
Forcing _get_printers() to return an empty set immediately after docstring works for me as a workaround for this issue.
Version info:
ii cups-bsd 1.3.8-7
ii cups-client 1.3.8-7
ii cups-common 1.3.8-7
ii cups-driver-gutenprint 5.2.0~beta4-0ubuntu1
ii hal-cups-utils 0.6.17+git20080728-0ubuntu2
ii jockey-common 0.4.1+r360-0ubuntu1
ii jockey-gtk 0.4.1+r360-0ubuntu1
ii python-cups 1.9.41-0ubuntu1
ii python-cupshelpers 1.0.5+git20080819-0ubuntu1
The indicated error in the jockey-<frontend> seems to be caused by jockey-backend script not finishing it's initialization stage, thus doesn't respond to frontend requests.
The jockey-backend script appears to be hanging in jockey. detection. _get_printers( ), while waiting on cups.Connection ().getDevices( ). In fact, the cupsd process goes to 100% CPU usage ocasionally and needs restart, so the real problem is probably in the cups/cups-client and jockey fails as a side-effect.
Forcing _get_printers() to return an empty set immediately after docstring works for me as a workaround for this issue.
Version info: gutenprint 5.2.0~beta4- 0ubuntu1 git20080728- 0ubuntu2 19-0ubuntu1
ii cups-bsd 1.3.8-7
ii cups-client 1.3.8-7
ii cups-common 1.3.8-7
ii cups-driver-
ii hal-cups-utils 0.6.17+
ii jockey-common 0.4.1+r360-0ubuntu1
ii jockey-gtk 0.4.1+r360-0ubuntu1
ii python-cups 1.9.41-0ubuntu1
ii python-cupshelpers 1.0.5+git200808