On 11/11/19 1:38 PM, Kent West wrote:
On 11/11/19 10:40 AM, Brian wrote:
On Mon 11 Nov 2019 at 10:18:26 -0600, Kent West wrote:
When adding a printer via the CUPS web interface (localhost:631) on my'ls -l /usr/lib/cups/backend' tells you that it doesn't matter what
Debian box, Administration / Add Printer / Other Network Printers, there are
four Internet Printing Protocol options:
https
ipp
http
ipps
Which one do I want to select? What are the differences?
choice you make.
lrwxrwxrwx 1 root root 3 Oct 31 02:44 http -> ipp
lrwxrwxrwx 1 root root 3 Oct 31 02:44 https -> ipp
-rwxr-xr-x 1 root root 80120 Oct 31 02:44 ipp
lrwxrwxrwx 1 root root 3 Oct 31 02:44 ipps -> ipp
Thank you. That does tell me they are all the same. It does not tell me why CUPS on Debian makes the other three options available (thereby confusing the person adding the printer). There must be some reason why a person would expect to choose X over Y; that's the difference I'm looking for.
After some testing, I find that selecting "http" creates a
working printer; selecting "ipps" does not. The latter generates
an error page that says:
Unable to open PPD file:
Missing asterisk in column 1
So apparently there is some difference between these protocols,
and I'm left wondering what the differences are, and which one I
should select.
--
Kent