Comment 4 for bug 385797

  * debian/local/text.convs: Turn all text input formats to text/plain at
    a high cost, so that the text-only printer (which accepts only text/plain)
    accepts them (LP: #385797).

I don't understand what's so costly about dumping text input straight to the printer. There shouldn't be anything required to do that. If we're whitelisting things, I think that there must be a better way.

For starters, we could identify source code correctly, with a MIME type of text/x-csource instead of application/x-csource. The latter implies that the source code may or may not be binary, when it isn't, it's source code, which _is_ plain text, not something that is costly to turn _into_ plain text. Seems like a decent stop-gap for the time being, but maybe another bug should be opened to detect formats correctly according to their major type (text, image, application, etc.)?

It also looks like the problem might be that CUPS wants to turn it into PDF as per /usr/share/cups/mime/texttopdf.convs, which contains:

Ubuntu Jaunty:[0-17/10295-0]:mime> cat texttopdf.convs
application/x-cshell application/pdf 0 texttopdf
application/x-csource application/pdf 0 texttopdf
application/x-perl application/pdf 0 texttopdf
application/x-shell application/pdf 0 texttopdf
text/plain application/pdf 0 texttopdf
text/html application/pdf 0 texttopdf

I don't see a PPD for my C500 printer (the one that is plain-text only). I have one for my e250dn, though, in the /etc/cups directory.