When you wrap your WordPress site in a native Android app using WebView, Google’s AdSense policy prohibits serving those ads through the app wrapper. You need to hide AdSense on mobile views while keeping them on desktop, and ideally detect when your site is loaded inside a WebView to block ads there too. Detecting Mobile…
Windows 7 stuck in an update loop—where Windows Update fails repeatedly and triggers automatic reboots—is a frustrating problem that stems from a corrupted or problematic update package. The system keeps attempting to install the same failed update on each boot, creating a cycle you can’t escape without intervention. Identify the Problematic Update The first step…
Many legacy projects require specific GCC versions that differ from your system default. Ubuntu makes this straightforward through the package manager and the update-alternatives system. Check available GCC versions First, see what versions are available in your distribution’s repositories: apt-cache search ^gcc- | grep -E ‘^\s*gcc-[0-9]’ For Ubuntu 20.04 and later, you’ll typically find GCC…
If you’re stuck at the Ubuntu login screen with errors like “Could not write bytes: Broken Pipe” or “Check Battery State,” the display manager is likely corrupted or misconfigured. This typically indicates a problem with LightDM, Ubuntu’s default display manager since 12.04. Understanding the Problem LightDM (the lightweight X display manager) manages your login session…
Finding and sorting files by modification time across directories is a common task for log rotation, cleanup scripts, and audit purposes. Here are the most practical approaches. Using find with printf (simplest method) The find command with -printf is the fastest and most portable approach: find . -type f -printf ‘%T@ %p\n’ | sort -rn…
When you need to check DNS records from a particular server—especially to verify changes on authoritative nameservers before they propagate through cached resolvers—use dig with the @ syntax to specify the target DNS server. Basic Syntax dig @DNS_SERVER domain.com Replace DNS_SERVER with the IP address of the nameserver you want to query, and domain.com with…
Forcing HTTPS on your website protects visitor data and improves SEO. The most common method is using .htaccess with Apache’s mod_rewrite module to redirect all HTTP requests to HTTPS. Basic HTTPS redirect Add this to your .htaccess file in the document root: RewriteEngine On RewriteCond %{HTTPS} !=on RewriteRule ^ https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301] This performs a permanent…
When you’re managing a Linux server remotely over SSH, determining whether a USB drive has been connected requires checking kernel messages and device listings since you can’t visually inspect the hardware. Check dmesg for USB Detection Events The most reliable method is examining kernel logs with dmesg. When a USB device is detected, the kernel…
The core problem here is legitimate: if you’re running multiple jobs on the same dataset where the mapper phase produces identical intermediate results, recomputing those results is wasteful. However, skipping the mapper phase entirely breaks MapReduce’s processing model. There are better approaches. Why You Can’t Just Skip the Mapper MapReduce assumes data flows through map…
The default dd command can feel sluggish because it uses a small block size (512 bytes) by default. You can dramatically improve throughput by increasing the bs (block size) parameter. Basic optimization Instead of: dd if=/dev/sda2 of=./sda2.bak Use: dd if=/dev/sda2 of=./sda2.bak bs=1M The bs parameter controls how much data dd reads and writes in each…
Measuring the execution time of a function is useful for profiling and optimization work. OCaml provides straightforward tools for this. Basic approach with Unix.gettimeofday The simplest method uses Unix.gettimeofday(), which returns wall-clock time as a float with microsecond precision: let time f = let t = Unix.gettimeofday () in let res = f () in…
When managing packages on Ubuntu or Debian systems, knowing what versions are available—and which one will be installed—is essential for dependency management and system stability. The aptitude command provides several ways to inspect package versions. Check all available versions of a package The most straightforward approach is to use the versions subcommand: aptitude versions package-name…
When backing up with rsync, you often need to skip directories like cache/, node_modules/, or .git/ that appear at multiple levels in your directory tree. Listing every instance individually is impractical, but rsync’s exclude patterns handle this elegantly. Basic exclude syntax The simplest approach uses –exclude with a directory name pattern: rsync -avxP –exclude=cache/ /path/to/src/directory/…
When you SSH to a server and see the warning below, your SSH client has detected that the server’s host key doesn’t match what’s stored locally: @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY! Someone could be eavesdropping on you right now (man-in-the-middle attack)!…
Removing version control or build artifact directories across a large directory tree is a common sysadmin task. SVN directories (.svn), Git metadata (.git), or node modules (node_modules) often need to be purged before deployment or archiving. Using find with xargs The most efficient approach combines find with xargs: find ./ -name “.svn” -type d |…
RTMP (Real Time Messaging Protocol) streams are still used for live broadcasts and on-demand video delivery, though less commonly than HLS or DASH. If you need to capture an RTMP stream, there are several solid tools available on Linux. Using ffmpeg (recommended) ffmpeg is the modern standard for working with RTMP streams. It’s widely available,…
GitBook is a tool for building documentation and ebooks from Markdown content. Here’s how to set it up on a Linux system. Prerequisites You’ll need Node.js installed first. On Ubuntu/Debian: curl -fsSL https://deb.nodesource.com/setup_20.x | sudo -E bash – sudo apt-get install -y nodejs On Fedora/RHEL: sudo dnf install nodejs Verify the installation: node –version npm…
When processing application logs (like Hadoop/log4j output), you often need to extract entries from a specific time window. This is especially common in automated routines that run periodically—for example, pulling the last 4 hours of logs every 4 hours via cron. Log format considerations Most application logs follow a consistent timestamp format. For example, log4j…
When you need to see what versions of a package are available in your Ubuntu repositories, there are several approaches depending on how much detail you need. Using apt-cache showpkg The most direct method is apt-cache showpkg, which lists all available versions along with their repository sources: apt-cache showpkg thunderbird This output shows version numbers,…
Linux Mint defaults to graphical mode, but you can boot directly to the console if you prefer a text-only environment or need to troubleshoot display issues. There are two main approaches: using GRUB parameters or disabling the display manager entirely. Method 1: Add the text kernel parameter (GRUB) This is the quickest approach and keeps…