Aggregating multiple RSS feeds into a single source is essential for monitoring diverse content — whether tracking news, blogs, project updates, or monitoring systems. Here are the practical approaches with working examples for 2026. Self-Hosted Feed Readers Miniflux is the modern standard for self-hosted feed aggregation. Written in Go, it’s lightweight, actively maintained, and provides…
The built-in etags command doesn’t recursively traverse directories by default, but generating TAGS files across your entire project is straightforward with the right tools and setup. Using ctags (Recommended) The simplest approach is ctags with the -e flag, which generates Emacs-compatible TAGS files: ctags -e -R . The -R flag enables recursive traversal. This works…
Bash provides comparison operators for conditionals through the test command (aliased as [), the [[ ]] compound command, and the (( )) arithmetic command. Each has specific use cases and behavior differences worth understanding. String Comparisons String comparisons work with test/[ and [[ ]]: Operator Meaning -n STRING String length is nonzero (true if not…
When you install a JDK on Linux, you need to configure environment variables so your shell uses the correct Java binary and build tools can locate the installation. If you have multiple Java versions installed, proper configuration becomes essential. Why Set Java Environment Variables Setting JAVA_HOME and PATH ensures: Tools and applications can locate the…
MPlayer is largely obsolete, but if you’re maintaining legacy systems, you’ll need to know how to position windows. For new work, use mpv (MPlayer’s maintained fork) instead. Centering with MPlayer Add this to ~/.mplayer/config: geometry=50%:50% This centers the window by setting both X and Y to 50% of screen dimensions. Override at runtime: mplayer -geometry…
Hadoop uses three primary configuration files to define YARN, HDFS, and MapReduce behavior: HDFS: hdfs-site.xml YARN: yarn-site.xml MapReduce: mapred-site.xml These files live in $HADOOP_HOME/etc/hadoop/ and override the built-in defaults when present. Finding Official Default Values Apache publishes default configuration documentation for each release. For current versions: Hadoop 3.4.x (Latest) HDFS defaults: https://hadoop.apache.org/docs/r3.4.0/hadoop-project-dist/hadoop-hdfs/hdfs-default.xml YARN defaults: https://hadoop.apache.org/docs/r3.4.0/hadoop-yarn/hadoop-yarn-common/yarn-default.xml…
YARN (Yet Another Resource Negotiator) fundamentally restructured Hadoop 2.0 by decoupling resource management from application logic. If you’re transitioning from Hadoop 1.x or building systems on top of YARN, understanding its architecture is essential for effective cluster administration and application development. Essential Reading The foundational paper Start with “Apache Hadoop YARN: Yet Another Resource Negotiator”…
Remapping modifier keys on Linux makes sense if you’re an Emacs power user, prefer ergonomic hand positioning, or simply don’t use the Win key. The standard approach moves frequently-used modifiers closer to your thumbs by trading the underutilized Super/Win key for additional Ctrl or Alt access. A typical remapped layout looks like: |Ctrl|Alt|Ctrl| Space Bar…
When you’ve modified your keyboard layout or key bindings using xmodmap and need to revert to the default, setxkbmap is your primary tool. However, the approach depends on whether you’re running X11 or Wayland, and what aspects of the configuration you want to reset. Check Your Session Type Before attempting any resets, verify whether you’re…
When compiling MapReduce jobs against a Hadoop installation, you need to include the correct classpath to resolve Hadoop dependencies. The yarn classpath command handles this automatically. Getting the classpath Run this command to output the full classpath: yarn classpath If yarn isn’t in your $PATH, use the full path: $HADOOP_HOME/bin/yarn classpath Replace $HADOOP_HOME with your…
Emacs makes heavy use of Ctrl, and many users find it ergonomically difficult to hit Ctrl repeatedly, especially on modern keyboards where Ctrl is placed far from home row. Swapping Alt and Ctrl can make Emacs navigation more comfortable. This guide covers modern approaches for different desktop environments and input systems. Emacs-Only Configuration (Simplest) If…
If you want Emacs to run in the terminal without opening an X window, you have several practical options depending on your setup and workflow. Option 1: Install emacs-nox (Recommended for servers) The cleanest approach is installing the no-X variant of Emacs, which is built without X11 support. This reduces memory overhead and startup time…
If you need to boot Windows from the GRUB2 command line—whether during troubleshooting, recovery, or when your boot configuration is broken—you can do it with a few commands. This guide covers both BIOS and UEFI systems. Quick boot for BIOS systems Assuming Windows is installed on the first partition of the first disk in NTFS…
If you need direct control over your firewall rules, you can disable firewalld and use iptables instead. This guide covers the setup process and best practices for maintaining persistent rules. Stop and disable firewalld If firewalld is currently running, stop it and prevent it from starting on boot: sudo systemctl stop firewalld sudo systemctl disable…
When you need to download large files faster, parallelizing across multiple connections can significantly improve throughput. Standard tools like wget and curl use single connections by default, but several alternatives support multi-connection downloads that can achieve 3-5x speedups on capable networks. aria2c aria2 is the most powerful option. It handles HTTP, HTTPS, FTP, BitTorrent, and…
The lp command is the standard tool for printing from the Linux command line. It interfaces with CUPS (Common Unix Printing System), the printing backbone on virtually all modern Linux distributions. Basic Printing Send a file to your default printer: lp text-file.txt Specify a particular printer: lp -d printer-name text-file.txt List available printers and identify…
Line number displays in Emacs can feel cramped without proper spacing. Modern Emacs provides built-in control over line number formatting and width—no external packages needed. Using display-line-numbers-mode display-line-numbers-mode is the standard in Emacs 25+ and should be your default choice. It’s faster and more maintainable than the older linum-mode. Enable it globally: (global-display-line-numbers-mode t) To…
If xterm displays Chinese, Japanese, or Korean characters as empty boxes or rectangles, the problem is almost always a missing or improperly configured font with CJK glyphs. Configure fonts in ~/.Xresources xterm reads font configuration from ~/.Xresources. Add these lines: XTerm*utf8: 1 XTerm*locale: true XTerm*faceName: Noto Mono XTerm*faceSize: 11 XTerm*faceNameDoublesize: Noto Mono XTerm*dynamicColors: true The…
Sharing a router with roommates means dealing with bandwidth conflicts. When someone’s running torrent clients, streaming, or other bandwidth-intensive applications without limits, everyone else suffers. Here’s how to handle it systematically. Start with conversation Before implementing technical controls, talk to your roommates. Most P2P and download applications have built-in rate limiting. Asking someone to cap…
These four languages share functional programming roots but diverge significantly in syntax and design philosophy. Here’s a practical reference for anyone transitioning between them or evaluating which to use. Basic Function Definition OCaml: let add x y = x + y let rec factorial n = if n <= 1 then 1 else n *…