How to determine that current instance of Node.js is running on Termux?

[irvnriir]

Preferably fully from the JS.

[AidenJastrzembski]

Assuming you don't have access to an ENV that has a platform var (because then you could just check that), you could write a function that was something along the lines of

    if (process.platform === 'android') {
        try {
            const fs = require('fs');
            // Check for Termux-specific directory
            return fs.existsSync('/data/data/com.termux/files/usr');
        } catch (error) {
            return false;
        }
    }

to check for termux!

[irvnriir]

Wouldn't this false-positive in other emulator when Termux is installed?

[dax-side]

You can determine if the current instance of Node.js is running on Termux by checking the PREFIX environment variable, which is unique to Termux. Here's a concise implementation:

const isTermux = () => {
const termuxEnv = process.env.PREFIX;
return termuxEnv && termuxEnv.includes('com.termux');
};

if (isTermux()) {
console.log('Running on Termux');
} else {
console.log('Not running on Termux');
}

Explanation:

1. Why PREFIX?
   In Termux, the PREFIX environment variable is set to /data/data/com.termux/files/usr, which identifies Termux's unique environment.

2. How It Works:
   The function checks for the existence of process.env.PREFIX and verifies if it contains the string com.termux, making it a reliable indicator.

3. Output:
   If running on Termux, the console will output Running on Termux; otherwise, it will output Not running on Termux.

[irvnriir]

This environment variable is set by Termux, but can be manually set on any system. So, though thats unlikely to happen, this can false-positive anywhere.

[ljharb]

It's not unique to termux - npm itself uses it.

[irvnriir]

My option with local config is more reliable.

[irvnriir]

Currently im using a config file per installation of app which runs on Node, its ignored in synchronization and Source Control, and contains specification of the type of system.

[dax-side]

Thank you for selecting my answer! Using a config file per installation is a smart way to manage system-specific settings, especially since it keeps the detection logic separate from your main code.

Ignoring the config file in source control is a good practice to avoid conflicts. If you ever need dynamic detection alongside the config file, you can still use methods like checking environment variables (e.g., process.env).

Let me know if you'd like to discuss more ideas!