If you use CUPS and cannot print from Qt based apps (like QCAD or Opera) because you see "lp" mentioned as your only printer while you do have other printers installed. It seems that this happens especially in Debian and Ubuntu, but I am not sure.

Try:
mv /etc/printcap /etc/printcap_old
ln -s /var/run/cups/printcap /etc/printcap

You have to do this as root. If matters are worse after this, copy the old printcap back.

(This solution was posted in the QCAD users group by Fred Dei-Cont. Since it provides a broader solution, *and* I had this problem with multiple applications I decided to post it here)

jlinkels

I have had problems printing (no printers showed up for me to choose) in QT applications on a newer version of Ubuntu - 7.04. This post helped me figure the problem out, although it wasn't straightforward. Here's how I fixed the problem...

cd /etc/cups/

(Use your favorite text editor - I use joe, which I had to do an apt-get install to get

sudo joe cupsd.conf)

Find line: Printcap /var/run/cups/printcap

Edit it out, and make a new line, so:

# Printcap /var/run/cups/printcap

Printcap /etc/printcap

Then restart cups:

sudo /etc/init.d/cupsys restart

Your QT based application should now print!

thank you, russianspi!
im with ubuntu 7.04 also and now it works.
spasibo, 4uvak!

Thanks a whole lot!! I am using Debian testing (Lenny). In Opera printing worked fine, but QCad showed no printers available.

My /etc/cups/cupsd.conf had no line with Printcap at all, so I just added one.

After restarting Cups, QCad had to be restarted also before the printer showed up, but it did!

Glad to see this is still helping people...

Also works fine in Ubuntu 8.04 with the Qt app FirstClass.
Thank you!

/J

EDIT: The same thing also work in Ubuntu Ibex 8.10

Thanks a lots, this was driving crazy curious kinda bug though