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.
The ls command is used to list directory contents when using the bash shell (and other shells), and has a variety of flags to choose what to display and how to format. This post shows how to list just the directories using ls.
cURL is an extremely useful command line tool for making HTTP requests and can be used for diagnosing errors, downloading content and so. But what if you just want to see the response headers to see, for example, if a page is doing the right sort of redirect?
When testing some website redirects with curl from the command line, I got the error message "curl: (3) [globbing] bad range specification in column 120"
This is a quick reference page for some tools for configuring web server settings and testing secure certificates.
I have a Debian virtual server running on VMWare Fusion and there’s no RAID setup configured. However, I kept getting emails with the subject "info: mpt raid status change on debian" so needed to switch the service off.
Rsync is a useful command line utility for synchronising files and directories across two different file systems. I recently needed to use rsync to only copy over files that did not already exist at the other end, so this post documents how to do this.