If you’ve compiled a kernel module for a specific kernel version or need to pin a package to prevent automatic updates, you’ll want to exclude it from yum or dnf. There are several approaches depending on whether you need a permanent exclusion, per-repository exclusion, or temporary lockdown. Global Exclusions in Configuration The simplest approach is…
Git branching is fundamental to modern development workflows. A branch is a lightweight pointer to a commit that lets you work on multiple features, fixes, or experiments in parallel without affecting the main codebase. Understanding branching well is essential for team collaboration and maintaining a clean project history. Creating and Switching Branches Create a new…
IBus daemon restarts aren’t always straightforward in GNOME, especially since menu options have been removed. You’ll need to kill the daemon and start a fresh one. Quick restart Kill the current IBus daemon: pkill -o ibus-daemon The -o flag terminates only the oldest process, which is typically the main daemon (not child processes). IBus usually…
Running Internet Explorer on Linux through Wine is theoretically possible but practically untenable. If you need to test in IE, understand upfront: Wine support for IE is broken, unmaintained, and will waste your time. Why IE on Wine Doesn’t Work Internet Explorer depends on a stack of Windows-specific components that Wine’s compatibility layer can’t reliably…
The sort command’s -n flag only handles decimal numbers. When you apply it to hexadecimal values, it falls back to lexicographic (alphabetical) sorting, which produces incorrect results since hex digits don’t follow numeric order alphabetically. Given a file with hex addresses: 400000000 __crt0 400000039 __newr0 400001B14 get_my_task_id 200000020 reg1 20400001000 status Running sort -n will…
Chrome aggressively caches HTTP redirects—especially 301 (permanent) and 308 redirects—as a performance optimization. The cache persists across browser sessions, which causes real problems when you’ve updated redirect rules and need to test them immediately. Understanding Chrome’s Redirect Cache Behavior Chrome stores redirect information at the browser level, separate from typical page caches. This means: 301…
GDM (GNOME Display Manager) lets you control which users appear on the login screen. You have two main options: hide the entire user list or exclude specific users while keeping the list visible for others. Disable the user list entirely The most straightforward approach is to disable user listing completely. This forces everyone to type…
You can fetch a webpage as if you’re requesting from a mobile device by setting curl’s User-Agent header to match a mobile browser. Remote servers use the User-Agent header to decide whether to serve mobile or desktop versions of pages. Basic syntax Use the -A (or –user-agent) flag to specify a mobile User-Agent string: curl…
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…
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…
When debugging a program or understanding what it actually touches on your filesystem, you need to see which files it opens. Two tools do this well: strace traces system calls in real time, while lsof inspects a running process without the overhead. Using strace to capture file operations The simplest approach is to run strace…
The replication factor determines how many copies of each data block HDFS maintains across your cluster. The default is 3, which provides adequate fault tolerance for most deployments by surviving both node and rack failures simultaneously. Setting Cluster-Wide Default Replication To set the default replication factor for all new files, add the dfs.replication property to…
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 effectively unmaintained. If you’re starting fresh, use mpv — the actively maintained fork with better codec support, hardware acceleration, and improved filter performance. That said, if you’re working with existing MPlayer setups, you can still improve playback quality through filters. When to Use Filters vs. When to Switch Before spending time tuning MPlayer,…
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”…
The Windows (Super) key can be remapped to function as an additional Ctrl key, useful if you work across multiple systems or prefer the extra modifier. The approach varies significantly by display server and desktop environment. GNOME (Wayland and X11) GNOME 3.38 and later have built-in remapping through Settings: Open Settings → Keyboard → Special…
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…
Memory leak detection is critical for C program reliability. Several tools work at different stages of development—compile time, runtime, and production scenarios. Your choice depends on performance tolerance, integration needs, and how much detail you require. AddressSanitizer (ASan) AddressSanitizer is the first tool to reach for in 2026. It’s compiler-integrated, fast, and catches a broader…