Linux Terminal Command: nohup

The nohup command is an essential tool in Process & Job Control. In this tutorial, we will explore what nohup does, look at everyday examples, and cover advanced options to supercharge your command-line workflow.

Concept & Explanation

The nohup command runs processes ignoring the SIGHUP (Hangup) signal, ensuring that background tasks continue running even if you close the terminal or log out.

Common Options & Syntax

nohup [options] [arguments]

Here are the most common flags used with nohup:

Simple Usage: Basic default commands.
Detailed View: Shows diagnostic information.
Advanced Actions: Can chain parameters for scripting.

1. Interactive Example (Simple)

Here is how most people run the command:

# Example
nohup python3 script.py &

What it does: Runs ‘script.py’ in the background, redirecting stdout to ’nohup.out’ and ignoring shell hangups.

2. Power-User Example (Advanced)

For scripting and advanced diagnostics, use this configuration:

# Advanced
nohup ./server > server.log 2>&1 &

What it does: Runs the server, redirects both output and error streams to ‘server.log’, and executes in the background.

⚙️ Warning & Common Pitfalls

[!WARNING] nohup does not automatically run commands in the background. You must append & to the end of the command to send it to the background.

Here are some related posts on cli_tty1 you might want to check out:

ps : Report a snapshot of the current processes.
top : Display Linux processes in real time.
htop : Interactive process viewer.