getIconByPid

Info

Retrieves the application icon for a process by its Process ID (PID). This function resolves the executable path from the PID using both .NET Process API and Win32 QueryFullProcessImageNameW as fallback, then extracts the icon. Returns an IconResult containing PNG data, or null if the process is not found.

Signature

function getIconByPid(pid: number): IconResult | null;

Parameters

Parameter	Type	Description
pid	number	Process ID (positive integer)

Usage

The getIconByPid function is useful when you already have the process ID from another API call, such as from Process.GetProcesses() or a monitoring event. It is part of the Application Icon Helper plugin.

Typical workflow:

1. Obtain the PID from process enumeration or monitoring.
2. Call getIconByPid(pid) with the numeric process ID.
3. Check if the result is null (process not found or no permission).
4. Use the returned IconResult (.data contains the PNG buffer).

Note

PID 0 is the System Idle Process and does not have an extractable icon. This function returns null for PID 0.

Tips

This function tries the .NET Process API first, then falls back to the Win32 QueryFullProcessImageNameW API for processes that require elevated permissions.

Return Value

Type	Description
IconResult | null	Icon result object, or null if process not found

Returns an IconResult object containing PNG icon data, size, and format. Returns null if the process is not found or inaccessible.

Warning

Access to process information may be restricted. If you don't have permission to query the process, this function returns null.

Example

TypeScript

import { getIconByPid } from '@eisland/windows-application-icon-helper';

// Get icon for current Node.js process
const result = getIconByPid(process.pid);

if (result) {
  console.log(`Current process icon: ${result.size} bytes`);
  // Convert to data URL for display in HTML
  const dataUrl = `data:image/png;base64,${result.data.toString('base64')}`;
} else {
  console.log('Could not retrieve icon');
}

// Get icon for a specific PID
const result2 = getIconByPid(1234);

// Returns null for invalid PIDs
const result3 = getIconByPid(0);        // System Idle Process
const result4 = getIconByPid(99999999); // Non-existent

JavaScript

const { getIconByPid } = require('@eisland/windows-application-icon-helper');

// Get icon for current Node.js process
const result = getIconByPid(process.pid);

if (result) {
  console.log(`Current process icon: ${result.size} bytes`);
  // Convert to data URL for display in HTML
  const dataUrl = `data:image/png;base64,${result.data.toString('base64')}`;
} else {
  console.log('Could not retrieve icon');
}

// Get icon for a specific PID
const result2 = getIconByPid(1234);

// Returns null for invalid PIDs
const result3 = getIconByPid(0);        // System Idle Process
const result4 = getIconByPid(99999999); // Non-existent

Notes

Note

The process must be currently running. If the process has exited between obtaining the PID and calling this function, it returns null.

Tips

If you have the process name instead of the PID, use getIconByProcessName for a simpler API that handles the process lookup internally.

Important

For the best performance when you already know the executable path, use getIconByPath instead. It avoids the process lookup step entirely.

Danger Avoidance

Caution

Do not assume that a PID is valid across reboots or even across short time spans. PIDs are recycled by the operating system. Always handle the null return case gracefully.