Ok, after a lot of testing and playing, it seems the driver-name in the toml does nothing.
That is too bad but not a big deal.
Lets start it differently then one very large big line.
We need to create a pipe....that is simple: mkfifo rsp1a.fifo
This simple command makes a special-pipe-file with that name.
Next we start the driver:
rx_sdr -f 435000000 -s 10000000 -d driver=sdrplay -g AGC=-20,IFGR=34,RFGR=1 -t rfnotch_ctrl=true,dabnotch_ctrlb=true -F CS16 - > rsp1a.fifo &
and a bit later we start the webssdr itself:
build/spectrumserver --config config-rsp1a.toml < rsp1a.fifo &
Why is this a better way?
Because you can restart the websdr software or the driver seperatly.
As such you also do more with systemd to check if both are running and restart if needed.
To bad the 'input.driver-name=' function isn't working in the code, else you could simply give the name of the pipe as name/device and it would start reading it.
But hey, it's a start to make things more simplistic.
Don't forget to make the 'pipe-file' else it will fill your harddisk in no time with a rubbish file ;D
I hope this makes it easier for people to make it run.
Also, you can make a cronjob for e.g. changing gains during day/night without kicking users....to name something.