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