When a disk fails on a server with multiple drives, you need to identify which physical SATA port it’s connected to. Linux device names (sda, sdb, etc.) don’t necessarily map to SATA port order, especially after disk failures or in systems with mixed storage. Using lsblk with Device Paths The lsblk command provides a quick…
Working in an SVN repository often leaves behind temporary build artifacts, compiled outputs, and editor cache files. Unlike Git’s git clean command, SVN has no built-in cleanup mechanism for untracked files. Using svn st to Identify Untracked Files The svn status command (or svn st) marks untracked files with a ? prefix. You can leverage…
Directory listing exposes your file structure to visitors and can be a security concern. Apache’s .htaccess file provides a straightforward way to disable this behavior while still allowing direct file access. Basic Implementation Create a .htaccess file in the directory where you want to disable listing: Options -Indexes Place this file in the root directory…
The caption LaTeX package provides customizable captions for floats (figures, tables, and other environments). It offers much more control than LaTeX’s default caption formatting. Install on Fedora The caption package is included in the texlive collection: # Install the full texlive collection (includes caption) sudo dnf install texlive-collection-latexrecommended # Or install just the caption package…
If you’ve made changes to your working copy but haven’t committed them yet, you can discard them using svn revert. This is useful when you want to abandon edits and go back to the last committed version. Basic Revert To revert all changes in your working copy, run this from the repository root: svn revert…
The wp_list_pages() function is the standard way to display child pages of a page in WordPress. This is useful for building navigation menus, sidebars, or displaying page hierarchies. Basic Implementation Here’s a working example that displays all child pages of the current page: <h3>Pages under <?php the_title(); ?></h3> <div class=”entry”> <ul> <?php wp_list_pages(array( ‘title_li’ =>…
MySQL Cluster uses NDB (Network Database) storage engine to provide high availability and data redundancy across multiple nodes. This guide covers installation and configuration on modern RHEL-compatible systems. Prerequisites Three or more servers (minimum: one management node, two data nodes, one SQL node) Rocky Linux 9 or AlmaLinux 9 Root or sudo access Static IP…
Standard Markdown syntax doesn’t include built-in parameters for image dimensions. The basic syntax  produces images at their original size or constrained by container width, with no way to specify explicit dimensions. If you need to control image size, you have several options depending on your use case and platform. HTML <img> Tag The…
Tracking branches link your local branch to a remote branch, enabling git pull and git push to work without specifying the remote and branch name each time. Here’s how to configure this. The basic command To set an upstream tracking branch for your current branch: git branch –set-upstream-to=origin/branch-name Or the shorter alias: git branch -u…
Swap space is essential for system stability, allowing the kernel to move less-frequently-used memory pages to disk when physical RAM is exhausted. Here’s how to set up a dedicated swap partition. Step 1: Create the Partition Use fdisk, gdisk (for GPT disks), or parted to create a new partition. For modern systems with GPT partition…
Linux can manage multiple swap partitions or files simultaneously, each with an assigned priority. The kernel allocates swap pages from highest to lowest priority, with round-robin allocation among equally-prioritized areas. Setting Swap Priority with swapon Use the swapon command to activate a swap partition and set its priority: swapon -p 10 /dev/sdc1 The -p flag…
GNOME uses .desktop files in ~/.config/autostart/ to launch applications when you log in. This mechanism works across GNOME, XFCE, KDE, and most other modern desktop environments. Basic Setup Create a .desktop file in ~/.config/autostart/. Here’s a minimal example: [Desktop Entry] Type=Application Name=My Autostart Script Exec=/home/user/bin/myscript.sh Save this as ~/.config/autostart/myscript.desktop and it will run on your…
iOS automatically pauses video playback when you lock your device to save battery and comply with app guidelines. If you want to listen to audio from a video while your screen is locked — say, watching a music video or podcast while walking — you need to enable background audio mode in your player app….
Taking photos with iPhone earphone remotes provides a practical way to reduce hand shake and camera blur, especially useful for self-portraits, group photos, or situations where you need stable hands-free operation. How to Trigger the Camera Press the volume-up button on your earphone remote to capture a photo. This works with the native Camera app…
GNOME Keyring stores passwords, SSH keys, and certificates. If you need to update your keyring password, you can do this through the Seahorse graphical interface or directly from the command line. Using Seahorse (GUI Method) Seahorse is GNOME’s visual keyring manager. Open it with: seahorse Once open: Go to the View menu and select By…
When you’re fighting page limits — conference submissions, journal requirements, or just fitting content on a poster — reducing LaTeX’s default spacing is essential. Here are the practical approaches, from gentle to aggressive. Basic Spacing Adjustments Start with the most impactful changes. These target the whitespace around floats (figures, tables) and captions: \setlength{\textfloatsep}{1pt} % Space…
To disable all active swap spaces on Linux, run: swapoff -a The -a flag targets all currently enabled swap devices and files. This forces the kernel and applications to rely entirely on physical RAM. When You’d Do This Disabling swap is useful for: Performance testing: Eliminating swap I/O variance to get consistent benchmarks Latency-sensitive workloads:…
The hex() function converts an integer to a hexadecimal string with a 0x prefix: i = 255 print(hex(i)) # Output: 0xff This works for negative numbers too: print(hex(-42)) # Output: -0x2a String formatting for control For more control over the output, use f-strings or the format() method with format specifiers: i = 255 print(f”Value: {i:x}”)…
To enable debugging, configure your CMake build with CMAKE_BUILD_TYPE set to Debug. This tells CMake to invoke the compiler with the -g flag, generating debug symbols that tools like gdb and lldb need. From your project’s root directory: cmake -DCMAKE_BUILD_TYPE=Debug -B build cd build make The -B build flag creates a separate build directory, which…
There are several ways to determine a file’s size in C, each with different trade-offs. Choose based on whether you have a file descriptor, stream, or just the filename. Using stat() with a Filename If you know the filename, stat() is the most straightforward approach: #include <sys/stat.h> #include <stdio.h> int main(const char *filename) { struct…