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projects:telegraph [2018/11/16 09:48] darronprojects:telegraph [2020/09/03 09:12] (current) – [User defined function] darron
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 </wrap> </wrap>
  
-Telegraph is a multi-purpose tool which provides sensor processing, data gathering, web graphing and status reporting. It is designed specfically for the Raspberry Pi and uses cheap and easily obtained sensor devices. An example device is the BME280 which can provide readings of ambient temperature, barometric pressure and relative humidity. BME280 boards can cost as little as 99p.+Telegraph is a multi-purpose tool which provides sensor processing, data gathering, web graphing and status reporting. It is designed specfically for the Raspberry Pi and uses cheap and easily obtained sensor devices. An example device is the BME280 which can provide readings of ambient temperature, barometric pressure and relative humidity. BME280 boards can cost as little as £2.50.
  
 Telegraph sensor processes are Simple Network Management Protocol (SNMP) daemon extensions which read data from various devices on a Raspberry or similar personal computer. The values returned can be used to populate a round robin (RRD) or SQL database either with Telegraph or a tool of your own choice. Telegraph sensor processes are Simple Network Management Protocol (SNMP) daemon extensions which read data from various devices on a Raspberry or similar personal computer. The values returned can be used to populate a round robin (RRD) or SQL database either with Telegraph or a tool of your own choice.
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  <graph label="C" />  <graph label="C" />
  <database type="rrd" filename="cpu.rrd" />  <database type="rrd" filename="cpu.rrd" />
- <query source="0" name="rpi" host="192.168.0.100" community="public" extend="cpu" />+ <query source="0" name="RPi" host="192.168.0.100" community="public" extend="cpu" />
 </telegraph> </telegraph>
 </code> </code>
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 === User defined function === === User defined function ===
  
-A user defined function may be forked every time Telegraph fetches new data. Forking allows a new process to be created and run in parrallel by the process creating the fork.+A user defined function may be forked every time Telegraph fetches new data. Forking allows a new process to be created and run in parallel by the process creating the fork.
  
-The configuration file has option added to achieve this.+The user option in the configuration file informs telegraph to fork the named process.
  
 <code> <code>