To determine file size in C, use stat() to populate a struct stat and read the st_size field. Here’s the correct approach: #include <sys/stat.h> #include <stdio.h> off_t file_length(const char *path) { struct stat st; if (stat(path, &st) == -1) { perror(“stat”); return -1; } return st.st_size; } Why off_t and not long Using off_t as…
When a process receives a signal from kill or pkill, it needs a signal handler to intercept and respond to it. Without one, most signals terminate the process immediately. This guide covers setting up robust signal handlers for production daemons. Understanding Signals The kill command sends signals to processes. By default, it sends SIGTERM (signal…
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…
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…
Line wrapping in Vim controls whether long lines display across multiple visual lines or extend beyond the window edge. This is purely visual—wrapping doesn’t modify your file. Understanding when to enable, disable, and configure wrapping is essential for different workflows. Enable and Disable Wrapping Enable soft wrapping to see long lines across multiple rows: :set…
Thunderbird wraps lines at a fixed character width by default during composition, which interferes with code snippets, preformatted text, and any content where line breaks matter. Here’s how to turn it off. Via Preferences The quickest method through the GUI: Open Thunderbird and go to Edit → Preferences (or Thunderbird → Settings on macOS) Navigate…
The primary keyboard shortcut for formatting code in Eclipse is Ctrl + Shift + F. This reformats your entire active file according to your configured code style settings without requiring any text selection. When you press Ctrl + Shift + F, Eclipse adjusts indentation, spacing, line breaks, and bracket placement across the file. To format…
Direct assignment to window.onload overwrites any existing handler. If a plugin, library, or another script has already set a handler, your code will replace it completely: // Plugin sets this window.onload = function() { initializePlugin(); } // Your code overwrites it window.onload = function() { doMyWork(); } // Result: initializePlugin() never runs This breaks plugins…
X11 forwarding lets you run Chrome on a remote host and display it on your local machine. It’s quick to set up for occasional use, but for regular work or modern Linux systems, you’ll want to know when to use alternatives. Basic X11 Forwarding The simplest approach uses SSH’s X11 forwarding: ssh -X username@remote_host google-chrome…
The most straightforward approach is whitespace-mode, which provides built-in visual feedback for lines exceeding a specified column width. Add this to your Emacs configuration: (require ‘whitespace) (setq whitespace-style ‘(face empty tabs lines-tail trailing)) (setq whitespace-line-column 80) (global-whitespace-mode t) The lines-tail style highlights only the portion of the line exceeding whitespace-line-column, which is less visually intrusive…
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…
If you’ve pushed a commit with a bad message, you can fix it—but the approach depends on whether others have pulled that commit yet. When Rewriting Is Safe Only amend and force-push if: You’re the only one using the repository You’re absolutely certain no one else has pulled the commit yet Your branch protection rules…
Viewing file contents in hexadecimal is essential for debugging binaries, inspecting file headers, analyzing corrupted data, and understanding file formats. Linux provides several tools for this, each with different strengths. xxd xxd is the most commonly used hex viewer. By default, it displays hex on the left and ASCII representation on the right: xxd file.txt…
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 simplest approach is to select text and run untabify: M-x untabify This replaces all tabs in the selected region with spaces, preserving column alignment. If no region is active, Emacs prompts you to define one. Convert the Entire Buffer Select all content, then run untabify: C-x h M-x untabify C-x h selects the whole…
Flash support ended in December 2020, and Adobe no longer distributes Flash Player. Most browsers dropped Flash entirely. If you’re stuck with legacy .swf files, here’s what actually works. Ruffle: Your Best Option Ruffle is the go-to solution. It’s an open-source Flash emulator written in Rust that handles most SWF files without needing Adobe’s player….
Emacs handles line ending conversions through its buffer coding system. Whether you’re converting CRLF (DOS/Windows) to LF (Unix) or the reverse, the process is straightforward. DOS to Unix (CRLF to LF) Open the file in Emacs and run: M-x set-buffer-file-coding-system RET undecided-unix Or use the keyboard shortcut: C-x RET f undecided-unix Then save the file:…
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…
To see the current file path immediately, use the Elisp evaluation prompt: M-: buffer-file-name This displays the full path in the echo area. Alternatively, press M-x, type eval-expression, and enter buffer-file-name. In Elisp code Reference buffer-file-name directly in your configuration or custom commands: (message “Editing: %s” buffer-file-name) This prints to the echo area and logs…
When you have multiple consecutive citations like [14], [15], [16], [17], [19], LaTeX renders them individually by default, wasting space. Citation management packages automatically compress these to [14–17], [19], which is standard practice for numerical citation styles. Using the cite Package The cite package is the simplest approach. Add it to your preamble: \usepackage{cite} When…