SysMon (Pi-mon)

Live, lightweight system monitor designed for the terminal (Raspberry Pi friendly). SysMon draws a persistent single- or multi-line status area at the top of your terminal showing temperature, CPU, RAM, voltage, disk read/write and network I/O. It also provides an optional desktop launcher.

Features

• Live per-second updates in the terminal (low overhead).
• Per-terminal background monitor so your shell prompt remains usable.
• Optional desktop launcher that opens a terminal running the monitor.
• Auto-detects best network interface and default terminal.
• Optional Raspberry Pi voltage reading via vcgencmd.
• Safe per-tty PID files to avoid duplicate monitors in the same terminal.

Requirements

• Linux with procfs (/proc and /sys) - developed for Raspberry Pi but works on other Linux systems.
• Bash (POSIX-ish; tested in bash).
• A real terminal device (must be run in a real tty; not a redirected/pipe environment).
• Optional: vcgencmd on Raspberry Pi for voltage readings.
• Optional: a desktop environment (for the desktop launcher).

Quick install (one line)

From a shell on the target machine:

curl -fsSL https://raw.githubusercontent.com/SheepTactics/Pi-mon/main/main%20bash | bash

or

wget -qO- https://raw.githubusercontent.com/SheepTactics/Pi-mon/main/main%20bash | bash

This installer will:

• install the monitor to ~/.local/bin/sysmon.sh
• install the launcher as ~/.local/bin/stat
• optionally add a Desktop entry ~/Desktop/SysMon.desktop when visual mode is selected
• add ~/.local/bin to your ~/.bashrc if needed

When the installer runs it prompts:

• 1 - Terminal command only (default)
• 2 - Terminal command + Desktop icon (visual mode)

Manual usage

• Start monitor in current terminal:
  • Run: stat (this starts the monitor in the current tty)
• Stop monitor in current terminal:
  • Run: stat stop
• Restart:
  • Run: stat restart
• Pass through to real coreutils stat:
  • stat FILE... will call the system stat if available.

If stat is not found immediately after install, refresh your shell:

export PATH="$HOME/.local/bin:$PATH"
hash -r

or open a new terminal.

What the monitor shows

• TMP: temperature in °C (if available via /sys/class/thermal)
• CPU: CPU usage as percentage
• RAM: RAM usage as percentage
• PWR: voltage (vcgencmd) if available
• R/W: disk read/write rate (KB/s or MB/s)
• I/O: network in/out (KB/s or MB/s)

How it works (brief)

• The stat launcher spawns sysmon.sh in the background for the current tty and creates a per-tty PID file in $XDG_CACHE_HOME (or ~/.cache).
• sysmon.sh queries /proc and /sys once per second, computes deltas for disk/network, and redraws a top status area by setting a terminal scroll region so your shell output scrolls below the status area.
• The monitor is careful to avoid duplicate instances for the same tty and cleans up terminal state when it exits.

Desktop launcher

If you install in visual mode the script will create ~/Desktop/SysMon.desktop. The installer tries to pick a terminal program from this list (first available): gnome-terminal, xfce4-terminal, lxterminal, mate-terminal, konsole, xterm, alacritty, kitty.

The .desktop file runs stat inside a terminal and leaves an interactive shell after stat exits.

Troubleshooting

• "SysMon must be run in a terminal." - ensure you're running stat in a real tty (tty prints /dev/pts/*).
• If stat does not start: check ~/.cache/sysmon-<tty_id>.pid and ensure no stale PID is blocking start.
• If images do not display on GitHub: the repo contains Sysmon-v1.0.1B and 2Sysmon-v1.0.1B used as example screenshots.
• Voltage shows N/A: you do not have vcgencmd or the platform doesn't provide the required PMIC values.
• To remove the desktop icon in terminal-only mode the installer deletes any existing ~/Desktop/SysMon.desktop.

Files in this repository

• main bash - Installer script (paste/curl this to run the installer).
• Sysmon-v1.0.1B, 2Sysmon-v1.0.1B - example screenshots/GIFs.
• (After install) files placed on user system:
  • ~/.local/bin/sysmon.sh - monitor script
  • ~/.local/bin/stat - launcher
  • ~/Desktop/SysMon.desktop - optional desktop launcher

Contributing

• Bug reports and pull requests welcome. Open an issue with details and a reproducible case.
• Please include terminal type, distro, and whether you're on Raspberry Pi when reporting hardware/temperature issues.