Unix is a multi-user, multi-tasking operating system that was initially developed by Bell Labs in the 1970s. Various similar operating systems that are POSIX compliant (ie compatible with Unix) have since been developed (POSIX is an abbreviation for Portable Operating System Interface for UNIX). These include the following: the BSD family (OpenBSD, FreeBSD, NetBSD, Mac OS/X), Solaris, IRIX, AIX, SunOS, UnixWare, OpenServer and Linux.
Software written for POSIX compliant operating systems is generally able to be compiled for all POSIX platforms with little or no platform-specific changes. This makes the commands and utilities available for this extended family of operating systems very similar, and there are few differences between administering them.
The articles in this section are about useful command line utilities and commonly used application software on POSIX compliant operating systems. For Mac OSX specific articles see my OSX section.
In Linux, users are those who use and operate the system. Groups are the aggregate of users. Groups make it easy for administrators to manage which users should have permission and access to certain information. These include the privileges to read, write, and execute. Apart from an organized system, security is a big factor to consider when configuring users …
The Linux operating system is a multi-user environment, where a system administrator will need to add users. As the system administrator, it falls to you to manage the system’s groups and users. This article discusses how to create new user accounts with the useradd command. Useradd Command Functions This is used to create user accounts in Linux. …
Copying directories on Linux is something that comes up quite often while administrating a Linux system. So how exactly do you copy a directory in Linux? This tutorial will show you how to copy files and directories in Linux using the cp command, rsync, and scp utilities. Copying Files and Directory – cp command How …
Eventually, you will need to have to read, write, and execute permissions on either a file or directory. To do this, you need to run the chmod command. This tutorial discusses how the chmod command functions, the basic permissions, its corresponding numbers, and everything else in between. What are chmod commands? Chmod means change mode. …
In Linux operating systems, groups allow collections of users permissions to specified resources. For someone to access the resources on a system, one must add a user to the corresponding group in Linux. Adding users to group is a task worth learning. It can help you manage your system better as well as provide security …
Vim/Vi is a popular text editor for many Linux software developers and system administrators. It’s especially true if you plan to debug any program errors or improve the script or program’s overall readability. Today, we’ll teach you how to display line numbers when you use vim/vi. Show or Hide Vim Line Numbers By default, Vim/Vi …