This is just a quick example of using the Linux DVB API to access a connected sat-tuner. (sat-receiver, dvb-adapter, dvb-s adapter, dvb-s2 tuner STB ...)
It is very basic but shows how to open, tune and get status from your tuner device.
It also shows how to setup a DEMUX filter to finally read filtered data from the tuner device.
Probably a good starting point to get acquainted with the basic Linux Kernel DVB API Framework.(without the LibDVBV5 interface)
There is only one Sourcefile and you can build easy like this:
cc DVBdemo.c -o dvb (or whatever name suits you)
Then run it: ./dvb
There are no parameters as everything is hardcoded for simplicity.
It assumes you have your Sat-Tuner connected via LNB to the Astra satellite.
and, of corse, your sat-tuner is connected to linux dvb driver.
If everything runs well, RTL Teletext data is saved in a file named "ttdata.bin" .
Have fun, xenpac ;)