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#php
#kotlin
#bash
#go
#sql
#rust
#typescript
#html
#java
#python
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#format
PHP
Stream Large CSV with Generator
Iterate over a CSV file row-by-row without ever loading the whole file into memory. Uses a generator so consumers can foreach naturally and PHP cleans up the file handle.
@admin
PHP
Human-Readable File Size
Format a byte count as a human-friendly string (KB / MB / GB / TB). Defaults to base-1024 sizes; pass base 1000 for SI units.
Rust
CSV Read/Write with the csv Crate
`csv` + `serde` lets you read/write CSVs directly into typed structs. No manual field parsing; column order tolerant via headers.
Bash
Recursive Directory Walker with Predicate
Use `find -print0` + `read -d ""` to safely iterate filenames that may contain spaces, newlines, or quotes. Standard bash for-loop over `find` output breaks on these.
Rust
Walk a Directory Tree
`walkdir` recursively iterates every entry under a path, skipping inaccessible directories cleanly. The standard-library alternative requires manual recursion.
PHP
Safe Path Join
Concatenate path segments and produce a normalized canonical path that resists "../" escape attempts. Throws if the result would land outside the given base directory.
PHP
Find Files Modified in Last N Days
List every file under a directory that was modified within the last N days. Useful for incremental backups or detecting stale entries.
PHP
Detect MIME Type via Magic Bytes
Use PHP's built-in finfo (libmagic) to detect a file's true MIME type from its bytes — not from the extension, which can be lied about. Critical for validating user uploads.
Bash
Idempotent Append to File
Add a line to a file (e.g., a config or PATH export) only if it isn't already present. Common in install/setup scripts that need to be safe to re-run.
Bash
Get Script's Own Directory
The "where am I" boilerplate that every nontrivial bash script needs. Resolves symlinks correctly with realpath, falls back gracefully if realpath is missing.
Bash
Atomic File Write (write then rename)
Write to a temp file in the SAME directory, then `mv` to the final name. mv on the same filesystem is atomic — readers never see a half-written file.
Go
Atomic File Write (temp + rename)
Write to a temp file in the SAME directory, then `os.Rename` to the final name. Rename is atomic on POSIX — readers never see a half-written file.
Bash
Read File Line-By-Line (the safe way)
The classic `for line in $(cat file)` is wrong — it word-splits and globbing fires on filenames. Use `while IFS= read -r line` with input redirection.
PHP
Atomic File Write
Write a file in a way that other processes never see a half-written state. Write to a temp file in the same directory, then rename — rename is atomic on POSIX filesystems.
PHP
Recursively Delete Directory
Remove a directory and everything under it. Defensive against symlinks (unlinks the symlink rather than recursing into it). Returns the count of items removed.
Java
Atomic File Write (move with ATOMIC_MOVE)
Write to a temp file in the same directory, then `Files.move` with `ATOMIC_MOVE` to the target. Readers never see a half-written file — critical for config / state files.
Rust
Atomic File Write (tempfile + persist)
Write to a temp file in the SAME directory, then atomically `persist` (rename). The `tempfile` crate handles cleanup if you crash before persisting.