# RRDtool

- Introduction
- Installing/Configuring
  - Requirements
  - Installation
  - Runtime Configuration
  - Resource Types
- Predefined Constants
- Examples
  - Procedural PECL/rrd example
  - OOP PECL/rrd example
- RRD Functions
  - rrd_create — Creates rrd database file
  - rrd_error — Gets latest error message
  - rrd_fetch — Fetch the data for graph as array
  - rrd_first — Gets the timestamp of the first sample from rrd file
  - rrd_graph — Creates image from a data
  - rrd_info — Gets information about rrd file
  - rrd_last — Gets unix timestamp of the last sample
  - rrd_lastupdate — Gets information about last updated data
  - rrd_restore — Restores the RRD file from XML dump
  - rrd_tune — Tunes some RRD database file header options
  - rrd_update — Updates the RRD database
  - rrd_version — Gets information about underlying rrdtool library
  - rrd_xport — Exports the information about RRD database
  - rrdc_disconnect — Close any outstanding connection to rrd caching daemon
- RRDCreator — The RRDCreator class
  - RRDCreator::addArchive — Adds RRA - archive of data values for each data source
  - RRDCreator::addDataSource — Adds data source definition for RRD database
  - RRDCreator::__construct — Creates new RRDCreator instance
  - RRDCreator::save — Saves the RRD database to a file
- RRDGraph — The RRDGraph class
  - RRDGraph::__construct — Creates new RRDGraph instance
  - RRDGraph::save — Saves the result of query into image
  - RRDGraph::saveVerbose — Saves the RRD database query into image and returns the verbose information about generated graph
  - RRDGraph::setOptions — Sets the options for rrd graph export
- RRDUpdater — The RRDUpdater class
  - RRDUpdater::__construct — Creates new RRDUpdater instance
  - RRDUpdater::update — Update the RRD database file