Programming languages and software development
Renaming a Git branch involves three steps: rename locally, push the new branch, and delete the old remote branch. How you do this depends on whether you’re working from the command line or your Git hosting platform’s UI. Rename the branch locally The simplest command renames a branch in your local repository: git branch -m…
Python’s standard library includes zoneinfo, which handles timezones correctly without external dependencies. Use it for all new code. from datetime import datetime from zoneinfo import ZoneInfo utc_time = datetime.now(ZoneInfo(“UTC”)) ny_time = utc_time.astimezone(ZoneInfo(“America/New_York”)) print(ny_time) This automatically manages Daylight Saving Time transitions. The IANA timezone database (via the tzdata package on Windows; built-in on Unix-like systems) backs…
Use the -d flag to run a container in the background and return terminal control immediately: docker run -d –name my-service my-image The container starts as a daemon process. Verify it’s running and check output: docker ps docker logs my-service Essential Configuration for Production Daemons A single -d flag isn’t enough for real workloads. Here’s…
Emoji rendering at incorrect sizes in Thunderbird usually comes down to font configuration. Unlike browsers that inherit system emoji rendering, Thunderbird manages its own font stack, which can drift out of sync with your system fonts or get corrupted in Thunderbird’s cache. Install a Color Emoji Font Start by ensuring you have a proper color…
GNOME’s natural scrolling setting can be frustrating — especially when the GUI option is missing or doesn’t apply to your mouse while leaving your touchpad alone. The issue usually comes down to your session type, GNOME version, and how input devices are registered on your system. Check your session type first Before troubleshooting, verify whether…
Thunderbird’s default feature set is deliberately minimal. Addons fill critical gaps for users managing multiple accounts, large archives, or specific workflow requirements. Here are the addons that solve genuine problems. Organization and Maintenance Remove Duplicate Messages Mail folders accumulate duplicates from IMAP syncing glitches, accidental re-imports, or migrations across devices. Remove Duplicate Messages scans folders,…
Go doesn’t have a dedicated FileExists() function. Instead, use os.Stat() to retrieve file metadata and inspect the error type to determine what actually happened. Basic File Existence Check import “os” func fileExists(path string) bool { _, err := os.Stat(path) return !os.IsNotExist(err) } os.Stat() returns an error only if something goes wrong. The key is using…
Local port forwarding on the same host requires understanding how netfilter processes packets based on their origin. The critical distinction: traffic from external sources hits the PREROUTING chain, but packets originating locally traverse the OUTPUT chain instead. Miss either one, and your forwarding won’t work. The core problem When you forward UDP port 500 to…
The simplest way to convert a string to lowercase is using the lower() method: >>> “Hello World”.lower() ‘hello world’ >>> “ABC”.lower() ‘abc’ >>> “abc”.lower() ‘abc’ The lower() method returns a new string with all uppercase characters converted to lowercase. The original string remains unchanged — strings are immutable in Python. Basic Usage text = “Python…
Traditionally, tools like strace used ptrace to monitor system calls. While effective for development debugging, ptrace stops the entire process for every syscall, causing 2-10x slowdown. This makes it unsuitable for production workloads where you need real-time visibility without tanking performance. Modern Linux offers significantly faster alternatives through eBPF (Extended Berkeley Packet Filter), which runs…
bbPress is WordPress’s standard forum plugin. When you need to modify how forum topics, replies, or other content displays, you’ll use WordPress filter hooks to intercept and transform the content before it reaches users. Common bbPress Content Filters Filtering Topic Content The bbp_get_topic_content filter runs after topic content is retrieved from the database but before…
PHP lets you call functions dynamically when you don’t know the function name until runtime. This is essential for plugin systems, routing handlers, API dispatchers, and configuration-driven logic. The approach you choose affects both performance and safety. Direct Variable Function Invocation The simplest approach treats a string variable as a callable: $func = ‘strlen’; echo…
The built-in pdb module is Python’s equivalent to gdb — a command-line debugger that lets you step through code, set breakpoints, inspect variables, and control execution flow. It’s essential for server-side debugging and situations where IDE graphical debuggers aren’t available. Starting a pdb Session Run a script through pdb directly: python -m pdb prog.py arg1…
iptables remains the standard firewall interface across most Linux distributions, though it’s technically a compatibility layer over nftables. Whether you’re managing legacy systems or prefer the familiar syntax, here’s what you need to know. Basic Command to Open a Port The fundamental syntax to allow inbound traffic on a specific port: sudo iptables -A INPUT…
Intercepting traffic before normal routing decisions requires understanding packet flow through iptables chains. If you need incoming packets to bypass the INPUT chain and process through FORWARD instead, you’ll use the PREROUTING chain with Destination NAT (DNAT). Packet Flow Through iptables When a packet arrives at your system, it traverses these chains in order: PREROUTING…
In Linux, everything is a file—including hardware devices. Block devices like disks, SSDs, and USB drives appear as files in /dev and handle I/O in fixed-size blocks. You need reliable ways to detect them in your Python scripts, especially when automating storage operations. Using pathlib (Recommended) Python 3.4+ provides pathlib.Path.is_block_device(), which is the modern standard:…
When you need to load configuration files, data files, or assets relative to your script’s location, the current working directory won’t work — it depends entirely on where you called the script from, not where the script actually lives. Use pathlib.Path: from pathlib import Path # The directory where the script lives script_dir = Path(__file__).resolve().parent…
The stat() system call is the traditional approach for checking file existence: #include <sys/stat.h> int file_exists(const char *path) { struct stat buffer; return (stat(path, &buffer) == 0); } This returns 1 if the file exists, 0 otherwise. The stat() call fills the buffer with file metadata, but when checking existence alone, you’re mainly interested in…
The Control Center in iOS provides the quickest way to toggle wireless connections. Here’s what you need to know across iOS versions. Accessing Control Center On modern iPhones with Face ID (iPhone X and later), swipe down from the top-right corner of the screen. On iPhones with a Home button (iPhone 8 and earlier), swipe…
MPlayer reached end-of-life in 2010 and hasn’t received updates since. If you’re still using it, you’re missing years of improvements in video decoding, filtering, and performance. For new projects, use mpv instead—it’s the maintained fork that incorporates MPlayer’s codebase with significant enhancements. That said, if you’re stuck maintaining legacy MPlayer setups, here’s how to optimize…