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Finding quality free images for your website means balancing availability, licensing, and actual usability. While generic image search works, specialized repositories are faster and legally safer. Google Image Search (with license filtering) Google Images remains useful for locating free content, but the licensing filter is critical. Use the Advanced Search and filter by usage rights…
Monitoring directory growth is essential for tracking logs, temporary files, and catching runaway disk usage before it becomes a problem. Linux offers several approaches depending on whether you need simple periodic checks, interactive exploration, or event-driven monitoring. Simple periodic monitoring The watch command repeatedly runs a command at set intervals: watch -n 1 du -sh…
When a process mmaps and mprotects many memory ranges, you’ll eventually hit the kernel limit and start seeing ENOMEM errors from mprotect() calls. This happens because Linux maintains internal kernel structures for each mapped range, and there’s a hard ceiling on how many the kernel will track per process. The culprit is the vm.max_map_count sysctl…
When you connect an external keyboard to your laptop, accidental key presses from the built-in keyboard can be annoying. Disabling it entirely is straightforward on Linux and can save you from errant inputs while keeping the option to re-enable it when needed. Find Your Keyboard Device Start by listing all input devices to identify your…
Writing a master thesis means protecting years of work. You need to handle three core concerns: preventing data loss from hardware failure or malware, ensuring 24/7 access to your work, and keeping it private until publication. The solution is version control with remote backup. Git provides local history and recovery, while a private remote repository…
Merging SAM files is a common task in bioinformatics workflows, and while samtools merge works directly with BAM files, you need a different approach for SAM files. The most efficient method leverages the SAM format structure: headers start with @, and alignment records don’t. Why not convert to BAM first? Converting SAM to BAM, merging…
The /etc/sysconfig/network-scripts/ directory contains network configuration files on RHEL and Fedora systems. While newer systems increasingly use NetworkManager and systemd-networkd, understanding ifcfg files remains essential for legacy systems and certain enterprise environments. Basic Static IP Configuration Here’s a typical ifcfg-eth0 file for a static IP setup: DEVICE=eth0 TYPE=Ethernet BOOTPROTO=none ONBOOT=yes IPADDR=192.168.1.151 NETMASK=255.255.0.0 GATEWAY=192.168.1.10 USERCTL=no The…
When submitting images to publishers or print shops, you’ll often need CMYK color space instead of RGB. The conversion is straightforward on Linux using ImageMagick’s convert command. Basic conversion The simplest approach uses the -colorspace option: convert from.tif -colorspace CMYK to.tif This works, but CMYK TIFF files can be quite large. Add compression to keep…
PowerPoint’s export function defaults to 96 DPI, which is suitable for screen display but inadequate for printing posters, documents, or any material requiring high resolution. While PowerPoint includes DPI settings, they’re often unreliable or have limited effect on TIFF output. Here are the practical methods to generate proper high-DPI TIFF files from PowerPoint slides. PowerPoint’s…
RealVNC’s free tier is limited to personal use and restricts advanced features, making it unsuitable for many production or semi-commercial scenarios. If you need a fully-functional open-source alternative, several solid options exist. TightVNC TightVNC remains a reliable choice for Windows VNC hosting. It’s GPL-licensed, fully open-source, and includes both server and client components. Installation: Download…
The git diff –word-diff output is clean and readable for tracking changes at the word level instead of line-by-line. If you need that functionality outside a git repository—or just want a standalone tool—wdiff is purpose-built for exactly this. Using wdiff for word-level diffs wdiff compares two files word by word, where a word is defined…
Many PDF-to-text conversions strip away formatting and spatial relationships, making tables unreadable and multi-column layouts collapse into linear text. If you need to preserve the relative positions of text elements—especially tables, columns, and indentation—you have several solid options. pdftotext with layout preservation The simplest approach is pdftotext, which comes with most distributions as part of…
When pushing to GitHub over HTTPS, you’ll see: error: The requested URL returned error: 403 Forbidden while accessing https://github.com/username/repo.git fatal: HTTP request failed This means Git connected to GitHub successfully, but your credentials were rejected. Common causes: Expired or revoked Personal Access Token (PAT) Using a password instead of a PAT (GitHub disabled password auth…
The TP-LINK T2U is a USB WiFi adapter based on the MediaTek MT7650U chipset. While Linux kernel support has improved significantly, you may still need to manually compile drivers on some distributions. This guide covers installation on modern Fedora and RHEL-based systems. Check if your adapter is already supported First, plug in the adapter and…
Firefox Sync requires an email address and a password to function. The critical question: if someone gains access to your Firefox account or device, can they read your synced passwords without knowing your master password? The short answer: no. Only you with your password can decrypt your synced data. Mozilla’s servers cannot access your encrypted…
The free command—along with ps, top, kill, pgrep, and dozens of other system utilities—is maintained as part of the procps-ng project. Source repository The source code is hosted at: https://gitlab.com/procps-ng/procps You can clone it with: git clone https://gitlab.com/procps-ng/procps.git cd procps Most distributions package procps-ng, so you likely already have it installed. You can verify the…
When you open a new window with window.open(), you often need to communicate between the parent (opener) window and the child (opened) window. The most straightforward approach is to access the opener window directly through the opener property. Basic Two-Way Communication In the parent window, define a variable: let exchangeVar = ”; From the child…
When you open a popup window with window.open(), you’ll often need to detect when the user closes it so you can update your UI, refresh data, or clean up resources. Here are the practical approaches, from polling to event-driven methods. Polling the closed property The simplest method is to periodically check the popup’s closed property:…
Serializing objects to JSON is a fundamental task in Node.js for APIs, databases, and file storage. The approach depends on your object complexity and performance requirements. Basic Conversion with JSON.stringify The standard approach uses the built-in JSON.stringify() method: const myObject = { name: ‘John’, age: 30, email: ‘john@example.com’ }; const jsonString = JSON.stringify(myObject, null, 2);…
Google Chrome can be installed on Fedora through Google’s official DNF repository. This method ensures you get automatic updates and the latest stable release. Add the Google Chrome repository Create a new repository file for Google Chrome: sudo dnf install fedora-workstation-repositories Then enable the Chrome repository: sudo dnf config-manager –set-enabled google-chrome Alternatively, if you prefer…