geekberg.info

The terminal emulator that ships with macOS is, by default, a black (background) and white (text) affair. In addition to a bland aesthetic, this lack of color has practical implications for the user. For example, the output of the ls command is muted, while

Sed--the stream editor--can read, then modify text on the fly. While the syntax for sed appears cryptic at first blush, it is a versatile text-processing tool worth adding to your UNIX utility belt. In the real world, one could use sed in combination with

At its core, the command line interface (CLI) grants users control over complex systems, and allows for the automation of tasks that would otherwise be cumbersome to manage manually. What follows is a brief transcript that helps to illustrate the point. last | awk '{

Here's a quick-and-dirty bash snippet that recursively locates all files ending with the .npy extension, and then replaces occurrences of a colon(:) with a dash (-) in their filename . For reference: find ./ -depth -type f -name '*.npy' \ -exec bash -c 'mv "$0&

Speed Test by Ookla is a web service that measures Internet connection performance metrics like download/upload rate, latency, and packet loss. The company offers a browser-based test, as well as several dedicated applications for the same, though you can bypass all of that

In our last post we discussed using Bash to transform data in one format to an arrangement suitable for import in to Google Groups. Now, let's take a soup-to-nuts look at the process. For reference, our source data takes the following format: # list-o-Steves # Stephen

In his book: "Automating the Boring Stuff", Al Sweigart details how to automate boring, repetitive digital tasks using the Python programming language. A job that could take hours of manual work, he explains, can be completed by a computer program faster--and with

In a previous post we detailed how to archive data "on-the-fly" from a local source to a remote destination, using the utilities tar, ssh, and cat. Today, we'll add nohup to that pipeline so that it can continue uninterrupted, irrespective of your

Setup Sendmail in GNU/Linux Scope: Set up a general-purpose internetwork routing facility that supports Simple Mail Transfer Protocol (SMTP). Dependencies Install these packages first, per your operating system (OS): Fedora, CentOS Debian, Ubuntu dnf install apt-get install sendmail-cf sendmail-cf mailutils mailutils sendmail sendmail

For the risk-averse among us, here are a few aliases that can reside in your shell initialization as insurance against the accidental removal of a file(s) or folder(s): alias cp="cp -i" alias mv="mv -i" alias rm=

One benefit of working from a terminal emulator is the ability to chain commands together in a way that would be difficult to do efficiently from a GUI. For example, the following snippet allows for "on the fly" compression and transfer of

Here's a quick code snippet for use in extracting the current highest user identifier (UID) in GNU/Linux using awk to do so. For reference: a UID is the unique value your UNIX-like operating system (OS) uses to identify an account and, when used

In a previous post, we shared a Bash shell script for creating local user accounts in GNU/Linux. As is often the case, the process of drafting this script yielded a number of useful code snippets, one of which we'll detail in this post.

For those running multi-user GNU/Linux instances not bound to a network identity management tool, there are a number of ways to provision local user accounts. As we're a fan of automating repetitive tasks such as the aforementioned, we'll examine how to handle silent

In a previous post, we discussed HTTP response codes, and shared a snippet for using curl to extract a website's response code for the purpose of checking if that site was accessible. Today, we'll show how to use wget to achieve the same effect.

"If a task is worth doing more than once, it's worth automating." -- Rando Lazy Programmer We were recently contacted with a straight-forward request: replace a portion of all file names in a given directory with an alternate name. For only a

For those who manage multi-instance environments, providing a descriptive identifier, i.e. a hostname, to each node on a network may be of some utility. Once you've developed a naming convention that makes sense for you, here's a Bash script that will automate the

When a client makes a request to a web site asking it to "serve" a given web page, an HTTP response code is generated by the server, indicating the status of the request. Broadly, there are five classes of HTTP status codes,

In Linux, the tar ("tape archive") command allows for the creation and extraction of archive files. Originally created to store file systems on to magnetic tape data storage, tar is commonly used to combine multiple files in to a single one for

For those of you connecting to multiple instances via SSH, setting up a local configuration file can save you the effort of having to keep track of things like: host names, user names, and command line switches. What follows is a quick guide on

In a previous post, we took a look at the critical role log files play in administering servers, and also dissected the content of an Nginx access log. With that information in mind, let's turn our attention to parsing out data points from the

If you are at all interested in the activity or performance of a web server under your charge, it is vital that you become familiar with the contents of /var/log. For your reference, the contents of this directory include: "Log files from

You may, on occasion, find yourself tethered to an insecure network or behind a firewall that restricts passage to a website. If you have access to an external network and a configured client a-la a virtual private network (VPN), you can bypass these limits

Welcome to the geekberg.info fiefdom. As our tagline suggests, we'd like for this site to serve as a gathering place for concise, functional tutorials of interest to "geeks". Frequently, when scouring the Internets for information on how to set up X