HardwareTemp Library Documentation

Overview

The HardwareTemp library is a C/C++ wrapper around the LibreHardwareMonitor .NET library, providing easy access to hardware monitoring capabilities including temperature readings, fan speeds, and other sensor data. The library consists of two main components:

HardwareWrapper.dll - A managed C++/CLI wrapper that interfaces with LibreHardwareMonitor
HardwareTemp.h/.dll - A native C++ library that provides a clean C-style API

Architecture

Your Application
       ↓
HardwareTemp.h (Native C++)
       ↓
HardwareWrapper.dll (C++/CLI)
       ↓
LibreHardwareMonitor (.NET)
       ↓
Hardware Sensors

Installation and Setup

Ensure HardwareWrapper.dll and LibreHardwareMonitor.dll and HidSharp.dll are in your application directory
Include HardwareTemp.h in your project or HardwareTemp.dll
Link against the necessary Windows libraries (Ole32.lib is automatically linked)

Error Codes

Code	Constant	Description
0	HWSUC	Success
-1	HWERR_MISS_FUNCTION	Function missing from DLL
-99	HWERR_NULL_FUNCTION	Function pointer is null

API Reference

Initialization and Cleanup

`InitHardwareTempMonitor()`

int InitHardwareTempMonitor();

Initializes the hardware monitoring system by loading the HardwareWrapper.dll and setting up all function pointers.

Returns: - 0 - Success or already initialized - > 0 - Windows error code from LoadLibrary - -1 - Failed to load required functions

Example:

int result = InitHardwareTempMonitor();
if (result != 0) {
    std::cout << "Failed to initialize hardware monitor: " << result << std::endl;
    return -1;
}

`ShutdownHardwareTempMonitor()`

void ShutdownHardwareTempMonitor();

Cleans up resources and unloads the HardwareWrapper.dll.

Example:

ShutdownHardwareTempMonitor();

`UpdateHardwareMonitorTemp()`

void UpdateHardwareMonitorTemp();

Updates all sensor readings. Should be called before reading sensor values to ensure fresh data.

Example:

UpdateHardwareMonitorTemp();
double cpuTemp = GetCpuTemperatureTemp();

Temperature Functions

`GetCpuTemperatureTemp()`

double GetCpuTemperatureTemp();

Gets the first CPU Package temperature.

Returns: - Temperature in Celsius - -1.0 - No sensor found - -99.0 - Function not available

Example:

UpdateHardwareMonitorTemp();
double temp = GetCpuTemperatureTemp();
if (temp > 0) {
    std::cout << "CPU Temperature: " << temp << "°C" << std::endl;
}

`GetAverageCpuCoreTemperatureTemp()`

double GetAverageCpuCoreTemperatureTemp();

Calculates the average temperature across all CPU Cores temperature

Returns: - Average temperature in Celsius of all "Core"-named sensors - -1.0 - No "Core" sensors found - -99.0 - Function not available

Example:

double avgTemp = GetAverageCpuCoreTemperatureTemp();
std::cout << "Average of Core Sensors: " << avgTemp << "°C" << std::endl;

`GetMaxCpuCoreTemperatureTemp()`

double GetMaxCpuCoreTemperatureTemp();

Gets the highest temperature among all CPU cores temperature

Returns: - Maximum temperature in Celsius among all "Core"-named sensors - -1.0 - No "Core" sensors found - -99.0 - Function not available

Example:

double maxTemp = GetMaxCpuCoreTemperatureTemp();
if (maxTemp > 80.0) {
    std::cout << "WARNING: Highest Core sensor reading: " << maxTemp << "°C" << std::endl;
}

`GetGpuTemperatureTemp()`

double GetGpuTemperatureTemp();

Gets GPU temperature. Automatically detects NVIDIA, AMD, or Intel GPUs.

Returns: - GPU temperature in Celsius - -1.0 - No GPU sensor found - -99.0 - Function not available

Example:

double gpuTemp = GetGpuTemperatureTemp();
if (gpuTemp > 0) {
    std::cout << "GPU Temperature: " << gpuTemp << "°C" << std::endl;
}

`GetMotherboardTemperatureTemp()`

double GetMotherboardTemperatureTemp();

Gets motherboard/system temperature.

Returns: - Motherboard temperature in Celsius - -1.0 - No sensor found - -99.0 - Function not available

`GetStorageTemperatureTemp()`

double GetStorageTemperatureTemp();

Gets storage device (SSD/HDD) temperature.

Returns: - Storage temperature in Celsius - -1.0 - No sensor found - -99.0 - Function not available

Fan Speed Functions

`GetCpuFanRpmTemp()`

double GetCpuFanRpmTemp();

Gets CPU fan speed in RPM.

Returns: - Fan speed in RPM - -1.0 - No fan sensor found - -99.0 - Function not available

Example:

double fanSpeed = GetCpuFanRpmTemp();
if (fanSpeed > 0) {
    std::cout << "CPU Fan Speed: " << fanSpeed << " RPM" << std::endl;
}

`GetGpuFanRpmTemp()`

double GetGpuFanRpmTemp();

Gets GPU fan speed in RPM.

Returns: - Fan speed in RPM - -1.0 - No fan sensor found - -99.0 - Function not available

`GetAllFanRpmsTemp()`

void GetAllFanRpmsTemp(char*** fanNames, double** rpms, int* count);

Gets all available fan sensors with their names and speeds.

Parameters: - fanNames - Output array of fan names - rpms - Output array of fan speeds - count - Number of fans found

Example:

char** fanNames = nullptr;
double* rpms = nullptr;
int fanCount = 0;

GetAllFanRpmsTemp(&fanNames, &rpms, &fanCount);

for (int i = 0; i < fanCount; i++) {
    std::cout << "Fan: " << fanNames[i] << " - Speed: " << rpms[i] << " RPM" << std::endl;
}

FreeFanDataTemp(fanNames, rpms, fanCount);

`FreeFanDataTemp()`

void FreeFanDataTemp(char** fanNames, double* rpms, int count);

Frees memory allocated by GetAllFanRpmsTemp().

Generic Sensor Functions

`GetAvailableSensorsTemp()`

void GetAvailableSensorsTemp(char*** sensorNames, int* count);

Gets a list of all available sensors in the system.

Parameters: - sensorNames - Output array of sensor names - count - Number of sensors found

Example:

char** sensorNames = nullptr;
int sensorCount = 0;

GetAvailableSensorsTemp(&sensorNames, &sensorCount);

std::cout << "Available sensors:" << std::endl;
for (int i = 0; i < sensorCount; i++) {
    std::cout << "  " << sensorNames[i] << std::endl;
}

FreeSensorNamesTemp(sensorNames, sensorCount);

`GetSpecificSensorValueTemp()`

double GetSpecificSensorValueTemp(const char* fullSensorName);

Gets the value of a specific sensor by its full name.

Parameters: - fullSensorName - Full sensor name (format: "Hardware Name - Sensor Type - Sensor Name")

Returns: - Sensor value - -1.0 - Sensor not found - -99.0 - Function not available

Example:

double value = GetSpecificSensorValueTemp("Intel Core i7-9700K - Temperature - Core #0");
if (value > 0) {
    std::cout << "Core #0 Temperature: " << value << "°C" << std::endl;
}

`FreeSensorNamesTemp()`

void FreeSensorNamesTemp(char** sensorNames, int count);

Frees memory allocated by GetAvailableSensorsTemp().

Complete Usage Example

#include "HardwareTemp.h"
#include <iostream>
#include <thread>
#include <chrono>

int main() {
    // Initialize the hardware monitor
    if (InitHardwareTempMonitor() != 0) {
        std::cout << "Failed to initialize hardware monitor!" << std::endl;
        return -1;
    }

    std::cout << "Hardware monitor initialized successfully!" << std::endl;

    // Monitor temperatures for 30 seconds
    for (int i = 0; i < 30; i++) {
        // Update sensor readings
        UpdateHardwareMonitorTemp();

        // Get temperatures
        double cpuTemp = GetCpuTemperatureTemp();
        double avgCpuTemp = GetAverageCpuCoreTemperatureTemp();
        double maxCpuTemp = GetMaxCpuCoreTemperatureTemp();
        double gpuTemp = GetGpuTemperatureTemp();

        // Get fan speeds
        double cpuFan = GetCpuFanRpmTemp();
        double gpuFan = GetGpuFanRpmTemp();

        // Display results
        std::cout << "\n--- Hardware Status ---" << std::endl;
        if (cpuTemp > 0) std::cout << "CPU Temperature: " << cpuTemp << "°C" << std::endl;
        if (avgCpuTemp > 0) std::cout << "Avg CPU Temperature: " << avgCpuTemp << "°C" << std::endl;
        if (maxCpuTemp > 0) std::cout << "Max CPU Temperature: " << maxCpuTemp << "°C" << std::endl;
        if (gpuTemp > 0) std::cout << "GPU Temperature: " << gpuTemp << "°C" << std::endl;
        if (cpuFan > 0) std::cout << "CPU Fan Speed: " << cpuFan << " RPM" << std::endl;
        if (gpuFan > 0) std::cout << "GPU Fan Speed: " << gpuFan << " RPM" << std::endl;

        // Wait 1 second
        std::this_thread::sleep_for(std::chrono::seconds(1));
    }

    // Cleanup
    ShutdownHardwareTempMonitor();
    return 0;
}

Error Handling

Always check return values and handle errors appropriately:

// Check initialization
int result = InitHardwareTempMonitor();
if (result != 0) {
    // Handle initialization error
    return -1;
}

// Check sensor readings
double temp = GetCpuTemperatureTemp();
if (temp == -99.0) {
    std::cout << "Hardware monitoring not available" << std::endl;
} else if (temp == -1.0) {
    std::cout << "CPU temperature sensor not found" << std::endl;
} else {
    std::cout << "CPU Temperature: " << temp << "°C" << std::endl;
}

Memory Management

Always free allocated memory:

char** sensorNames = nullptr;
int count = 0;
GetAvailableSensorsTemp(&sensorNames, &count);

// Use the sensor names...

// Don't forget to free!
FreeSensorNamesTemp(sensorNames, count);

Threading Considerations

The library is not thread-safe
Call UpdateHardwareMonitorTemp() from the same thread that reads sensor values
Consider using mutex protection if accessing from multiple threads

Supported Hardware

The library supports hardware monitoring through LibreHardwareMonitor, which includes:

CPUs: Intel, AMD processors
GPUs: NVIDIA, AMD, Intel graphics cards
Motherboards: Various chipsets
Storage: SSDs, HDDs with temperature sensors
Fans: Case fans, CPU coolers, GPU fans

License

This library is released under the MIT License.