Hallo Henrik,

the last Days were a litle bit cold in germany. So i found that rrd/do_temperature.c dont work correctly on negative values ...

In the part:

		p = bol + strlen(bol) - 1;
		while ((p > bol) && isspace((int)*p)) p--;
		while ((p > bol) && isdigit((int)*p)) p--;
		tmpF = atoi(p);
		while ((p > bol) && isspace((int)*p)) p--;
		while ((p > bol) && isdigit((int)*p)) p--;
		tmpC = atoi(p);

there have be two additional lines of code:

		p = bol + strlen(bol) - 1;
		while ((p > bol) && isspace((int)*p)) p--;
		while ((p > bol) && isdigit((int)*p)) p--;

--> while ((p > bol) && *p == '-') p--; tmpF = atoi(p); while ((p > bol) && isspace((int)*p)) p--; while ((p > bol) && isdigit((int)*p)) p--; --> while ((p > bol) && *p == '-') p--; tmpC = atoi(p);

The rrd-File has to bee build with another Minimum for the Values stored. I dont find the code for the creation, but "rrdtool tune temperature.sensor4.rrd -i temperature:-10" did the job for my environment.

please insert the lines of code into do_temperature.c

greetings

to All: (after christmas) I wish you a happy new year

Rolf