Xerox gui freezes when printing via CUPS

[Darren Pifer]

Hello,

I am posting this message in the development forum in hopes that one of the development team can give me some insight, especially since I had to make a change to the software:

I am trying to get CUPS working with Xerox's CentreWare print software but I am having an issue with the Xerox gui hangs during the print process. This is what I do: on the client I type the command 'lp -d<printer> /etc/hosts' which looks up the printer via the /etc/printers.conf file. The printers.conf file has entry like:

printer-uri-supported=lpd\://<printserver>

On the server, the printers have been added via the Xerox xpadmin utility to print servers printers.conf file and interfaces are added accordingly. In order to get the display to open on the client, I had to add about 5 lines to job.c to set up the environment. After rebuilding the CUPS software, it works. However, when I print, the Xerox gui will pop up and when I click on the "print" button, the interface will freeze, anywhere from a few seconds to 30 seconds. To alleviate this issue, I have tried various configuration changes, like changing TIMEOUT to 0 and other timeout configuration settings. The timeout has improved the situation but not completed. There is still some delay where the gui will freeze for a while and then disappear. Printing does work, it is I am having the issue where the gui hangs. BTW, I am using CUPS 1.4.5 and Xerox 4.30.18 CentreWare software on a Linux CentOS machine.

I discovered that after adding some debug print statements to the software that the issue has something to do with the epoll_wait system call, as that is where the extra time is getting added. What is add is that this issue is with only one interface script.

I appreciate any pointers or resolutions.

Regards, Darren Pifer
ODU - CCPO