getTemperature

Introduction

getTemperature is a synchronous function that returns a snapshot of all hardware temperature sensors reported by the LibreHardwareMonitor helper process. It reads CPU, GPU, motherboard, and storage temperatures and bundles them into a single TemperatureSnapshot object. This is the primary way to poll real-time thermal data from eIsland plugins.

Signature

function getTemperature(): TemperatureSnapshot

The function takes no parameters and returns immediately. All sensor data is collected from the LibreHardwareMonitor helper EXE's shared state, so the call is fast and non-blocking.

Usage

getTemperature is designed for periodic polling. Call it on a timer (e.g., every 1-5 seconds) to build a temperature monitoring dashboard or trigger thermal warnings.

Best Practice

Call getTemperature at a fixed interval using setInterval or a framework-level scheduler. Avoid calling it in tight loops — while the call is fast, the underlying sensor data only updates at the helper process's refresh rate (typically once per second).

Snapshot Semantics

Each call returns a point-in-time snapshot. The readings array may change between calls as sensors appear or disappear. Always check isAvailable before accessing readings.

Typical workflow:

1. Call getTemperature() to obtain a TemperatureSnapshot.
2. Check isAvailable — if false, the helper EXE is not running or no sensors were detected.
3. Iterate over readings to display per-sensor data, or use maxTemperatureCelsius for a single headline value.

Return Value

Returns a TemperatureSnapshot object with the following shape:

Field	Type	Description
isAvailable	boolean	true if the helper EXE is running and at least one sensor is reporting.
readings	TemperatureReading[]	Array of individual sensor readings. Empty if isAvailable is false.
maxTemperatureCelsius	number | null	The highest temperature across all sensors. null when isAvailable is false or no sensors report valid data.

Null Safety

maxTemperatureCelsius can be null. Always guard against it before performing arithmetic or comparisons:

const max = temp.maxTemperatureCelsius ?? 0;

Properties

TemperatureReading

Each entry in the readings array is a TemperatureReading object:

Field	Type	Description
id	string	Unique identifier for the sensor (e.g., 'cpu-0', 'gpu-0').
label	string	Human-readable sensor name (e.g., 'CPU Core #1', 'GPU Core').
category	TemperatureCategory	One of 'cpu', 'gpu', 'motherboard', 'storage', or 'unknown'.
temperatureCelsius	number	Current temperature in degrees Celsius.
source	'libre-hardware-monitor'	Data source — always 'libre-hardware-monitor' for this plugin.

Filtering by Category

Use the category field to group readings. For example, to show only CPU temperatures:

const cpuTemps = temp.readings.filter(r => r.category === 'cpu');

Example

TypeScript

import { getTemperature } from '@eisland/windows-performance-monitor';
import type { TemperatureSnapshot } from '@eisland/windows-performance-monitor';

// Poll temperature every 2 seconds
setInterval(() => {
  // Get the current temperature snapshot
  const temp: TemperatureSnapshot = getTemperature();

  // Check if the helper EXE is available and sensors are reporting
  if (!temp.isAvailable) {
    console.warn('Temperature unavailable — ensure eIslandTemperatureReader.exe is running');
    return;
  }

  // Display the highest temperature across all sensors
  console.log(`Max: ${temp.maxTemperatureCelsius}°C`);

  // List each sensor reading with its category
  temp.readings.forEach(r => {
    console.log(`  ${r.label} [${r.category}]: ${r.temperatureCelsius}°C`);
  });
}, 2000);

JavaScript

const { getTemperature } = require('@eisland/windows-performance-monitor');

// Poll temperature every 2 seconds
setInterval(() => {
  // Get the current temperature snapshot
  const temp = getTemperature();

  // Check if the helper EXE is available and sensors are reporting
  if (!temp.isAvailable) {
    console.warn('Temperature unavailable — ensure eIslandTemperatureReader.exe is running');
    return;
  }

  // Display the highest temperature across all sensors
  console.log(`Max: ${temp.maxTemperatureCelsius}°C`);

  // List each sensor reading with its category
  temp.readings.forEach(r => {
    console.log(`  ${r.label} [${r.category}]: ${r.temperatureCelsius}°C`);
  });
}, 2000);

Notes

Helper EXE Dependency

This function relies on the eIslandTemperatureReader.exe helper process. The helper uses LibreHardwareMonitor to access low-level hardware sensor data. If the helper is not running, isAvailable will be false and readings will be an empty array.

Sensor Availability Varies by Hardware

Not all systems expose the same set of sensors. Some machines may only report CPU temperatures; others may include GPU, motherboard, or storage sensors. The category field with value 'unknown' indicates a sensor that LibreHardwareMonitor could not classify.

Use maxTemperatureCelsius for Quick Checks

If you only need a single thermal headline value (e.g., for a floating widget badge), use maxTemperatureCelsius instead of iterating readings. It is pre-computed and avoids unnecessary array traversal.

Danger Avoidance

Do Not Access readings Without Checking isAvailable

If isAvailable is false, the readings array is empty and maxTemperatureCelsius is null. Skipping the isAvailable check will lead to null reference errors or silent failures downstream. Always check the flag first.

Avoid Excessive Polling Frequency

Calling getTemperature in a tight loop (e.g., every 10ms) will not yield fresher data — the helper EXE updates at its own refresh rate. Excessive calls waste CPU cycles without benefit. A 1-5 second interval is sufficient for most UI use cases.

Do Not Assume Specific Sensors Exist

Never hardcode assumptions about which sensor IDs or categories will be present. A system without a discrete GPU will have no 'gpu' readings. Write defensive code that handles an empty readings array gracefully.