Several plural forms of Unix are used casually to refer to multiple brands of Unix and Unix-like systems. Most common is the conventional Unixes, but Unices, treating Unix as a Latin noun of the third …

May 2, 2025 · In bash, $0 is a special parameter that holds the name of the script or shell that is currently being executed. It is also known as the “name” or “zeroth argument” of the script. For …

Sep 14, 2012 · In Bash, there appear to be several variables which hold special, consistently-meaning values. For instance, ./myprogram &; echo $! will return the PID of the process which backgrounded …

Jul 6, 2024 · What Are the Special Dollar Sign Shell Variables? 1. Overview. The dollar sign ($) plays a crucial role in shell scripting. This ranges from argument handling to process management, and even …

Knowing basic Unix commands should allow you to navigate your Unix or Linux system, confirm current system status and manage files or directories. UPDATE 09/2024: I’ll be publishing a short video …

Nov 15, 2025 · UNIX is a multitasking and multiuser operating system designed to provide a stable, secure, and efficient computing environment. It was originally developed at AT&T Bell Labs and later …

From this page you can read about the history of the UNIX system over the past 40 years or more. You can learn about the Single UNIX Specification, and read or download online versions of the …

Sep 17, 2008 · Every process in a UNIX like operating system has a (temporarily) unique identifier, the PID. No two processes running at the same time can have the same PID, and $$ refers to the PID of …

Easy epoch/Unix timestamp converter for computer programmers. Includes epoch explanation and conversion syntax in various programming languages.

This is because those characters are used in the names of special Unix variables. These variables are reserved for specific functions. For example, the $ character represents the process ID number, or …