Posts
Linux Basics: Match Sorted Text Records with GNU join
Two simple exports may share an identifier but contain different columns. GNU join matches sorted input records by a key. Use a deliberately small delimiter-separated fixture to …
October 27, 2026
Linux Basics: Copy Files with Explicit Modes Using GNU install
A local staging directory often needs predictable permission bits. GNU install can create parent directories and copy a file with an explicit mode. Practice only inside a fresh …
October 27, 2026
Linux Basics: Combine Lines by Position with GNU paste
Sometimes two files already have corresponding rows and need to be displayed side by side. paste combines lines by position. An uneven fixture makes the missing-row behavior …
October 27, 2026
JavaScript Basics: Match URL Components with URLPattern
A route check should distinguish a URL path from its host and protocol. URLPattern matches components and exposes named groups. Build a fixed HTTPS origin pattern, then test …
October 27, 2026
JavaScript Basics: Manage Local Listeners with EventTarget
A local component can notify listeners through EventTarget without using a browser DOM. Node supports one-shot listeners, abortable registrations, and cancelable events. The …
October 27, 2026
JavaScript Basics: Inspect OS Capabilities Without Dumping Host Details
A diagnostic probe often needs capabilities rather than hostnames, usernames, or complete network addresses. Node’s os module exposes platform information. This example validates a …
October 27, 2026
JavaScript Basics: Consume Timer Ticks with an Async Iterator
A periodic local task can consume ticks with for await instead of registering a repeating callback. Node’s promise-based interval returns an async iterator. Stop a finite loop …
October 27, 2026
JavaScript Basics: Adapt Error-First Callbacks with promisify
Legacy APIs often finish through a callback whose first argument is an error. util.promisify adapts that convention to a promise. A tiny fixture checks successful results, rejected …
October 27, 2026
Git Basics: Transfer Committed History with a Bundle
A disconnected machine can receive a Git repository without a server. A bundle stores reachable Git objects and named references in one file. Practice a complete transfer and an …
October 27, 2026
Git Basics: Search Working Files, the Index, and Commits
A search result depends on which version of a file you inspect. git grep can search tracked working files, staged content, or a named commit. Comparing all three is useful when an …
October 27, 2026