The latest articles on DEV Community by fralsare (@fralsare). https://dev.to/fralsare https://media2.dev.to/dynamic/image/width=90,height=90,fit=cover,gravity=auto,format=auto/https:%2F%2Fdev-to-uploads.s3.us-east-2.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F4128492%2F32354598-5354-4287-9ea5-2e97eafa2d23.png https://dev.to/fralsare en fralsare Thu, 24 Sep 2026 12:32:03 +0000 https://dev.to/fralsare/how-i-built-a-linux-cli-that-auto-pauses-your-active-time-3917 https://dev.to/fralsare/how-i-built-a-linux-cli-that-auto-pauses-your-active-time-3917 <p>A few weeks ago I wanted something simple: a way to see how much of my day I was actually using my computer versus just sitting at it. My existing time trackers counted every idle minute as wasted, which felt wrong - I wasn't being lazy, I was just… not doing anything.</p> <p>So I built timerCLI, a tiny command-line tool that tracks your active time and automatically pauses it whenever you go idle.</p> <h2> The core idea </h2> <p>The trick is simple but clever: Linux exposes raw input device events at /dev/input/event*. These are the kernel-level files that capture every keyboard press, mouse movement, and touch event.</p> <p>All timerCLI does is:</p> <p>Open every readable /dev/input/event* device (non-blocking)<br> Continuously drain any pending input events<br> Track the timestamp of the last event<br> If no input arrives for IDLE_LIMIT seconds (default 30s), pause the timer<br> Resume the instant input returns<br> That's the entire engine — no machine-learning, no tracking servers, no telemetry. Just raw input watching.</p> <h2> What the output looks like </h2> <p>Idle: 0s | Active: 00:04<br> ⏸ Idle 31s — pausing…<br> ▶ Resumed.<br> Idle: 0s | Active: 00:41 ← keeps counting down while paused</p> <p>When you stop typing/moving for 30 seconds, it pauses and shows a ⏸️ indicator. The moment you use your computer, it's back to counting active time. Stop it anytime with Ctrl+C and it prints your final active/paused totals.</p> <h2> Why keep it tiny? </h2> <p>I deliberately wrote this using only Python's standard library - no psutil, no pyautogui, no dependencies to install. That means:</p> <p>It runs on almost any Linux box with Python 3<br> Nothing to pip install<br> Easy to read and modify<br> The only real requirement is permission to read /dev/input/event*, which needs your user in the input group:</p> <p>sudo usermod -aG input $USER # then log out and back in</p> <h2> It's open source </h2> <p>timerCLI is MIT licensed and fully open source. You can read the whole thing in a few hundred lines here:</p> <p>👉 <a href="https://github.com/fralsare/timerCLI" rel="noopener noreferrer">timerCLI</a></p> <p>I built it as a learning project, but I'd love for people to actually use it. I'm also accepting donations (GitHub Sponsors + UPI) to fund my cybersecurity studies - every bit helps. 🙏</p> cli linux productivity tools