Import settings from other file into config.txt

Question

Is it possible to import settings from another file into config.txt?

As I imagine

config.txt example content:

...

# Uncomment this to enable the lirc-rpi module
#dtoverlay=lirc-rpi
# Additional overlays and parameters are documented /boot/overlays/README
# Enable audio (loads snd_bcm2835)
dtparam=audio=on

...

include="/home/pi/mysettings.txt"

Why I want to do that

I mount the boot partion readonly. Sometimes I need to change some settings.

---

So I have to:

1. modify fstab (make boot partionen writeable)
2. restart
3. change config.txt
4. restart, test settings, maybe back to 3.
5. modify fstab (make readonly)
6. restart
7. done

---

What I want to do:

1. change mysettings.txt
2. restart, test settings, maybe back to 1.
3. done

Answer 1

This is not possible. Dokumentation of config.txt says:

This (rem.: config.txt) is read by the GPU before the ARM CPU and Linux are initialised. It must therefore be located on the first (boot) partition of your SD card, alongside bootcode.bin and start.elf.

edit: But on Raspbian you can simply remount the partition read/write:

pi ~$ sudo mount -o remount,rw /boot

Do your work, then remount the partition back to read only:

pi ~$ sudo mount -o remount,ro /boot