Manually edit ACPI thermal trip point temps & types?

[John Hupp]

In accord with http://ubuntuforums.org/showthread.php?t=2088043 I also 
tried these:

$ echo -n active | sudo tee trip_point_1_type
and
$ sudo sh -c "echo -n active > trip_point_1_type

Both of these also failed with Permission denied errors

On 6/4/2014 7:42 PM, John Hupp wrote:
> I have a Lenovo 3000 C200 running Lubuntu 14.04.  It has support for 
> ACPI thermal management (e.g. there is a tree at /sys/class/thermal).  
> And to be clear, there are no thermal management settings in the BIOS.
>
> The current trip point temp is set high and the type is passive-only.  
> I'd like a lower temp with active (fan) type.
>
> I have not found a current tool that knows how to manage these 
> things.  That was the idea behind acpitool, but it is looking for 
> files at the deprecated locations at /proc/acpi, so it seems to be in 
> need of an update.
>
> So I wanted to see what would work manually.
>
> From /sys/class/thermal/thermal_zone0 I tried:
> $ echo -n 40 > trip_point_1_temp
> bash: trip_point_1_temp: Permission denied
> $ echo -n active > trip_point_1_type
> bash: trip_point_1_temp: Permission denied
>
> I tried the same commands with sudo, with the same results.
>
> I also repeated the exercise from 
> /sys/devices/virtual/thermal/thermal_zone0, which is where links from 
> the above location point.  Same results.
>
> Some things in /sys are meant to be read-only, but the thermal_zone 
> attributes should be writable (somehow).
>
> Anyone know how?
>
> And if that succeeds, I imagine that the current defaults would be 
> re-established at reboot.  So I'm also wondering about the best way to 
> make any changes permanent.
>