Tags
#php
#kotlin
#bash
#go
#sql
#rust
#typescript
#html
#java
#python
#files
#utils
#strings
#http
#concurrency
#async
#json
#arrays
#security
#types
#crypto
#database
#dates
#format
Go
Read File — Whole / Lines / Bytes
Three common patterns: load it all (`os.ReadFile`), iterate line-by-line with `bufio.Scanner`, or stream chunks via `io.Reader`. Pick by file size.
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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.
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.
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.
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.
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.
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
CSV Read/Write with encoding/csv
`encoding/csv` parses RFC 4180 CSVs. Read row-by-row with `Read()` or all at once with `ReadAll()`. Same for writing — flush with `Writer.Flush()` before closing.
Python
Safe JSON Read/Write
Idiomatic helpers for reading + writing JSON to disk, with atomic writes and pretty-printed output. Catches the common "edit and save → corrupt file on crash" failure mode.
Kotlin
Write to a File
`writeText` overwrites; `appendText` appends. For multiple writes, use `bufferedWriter().use { }` for efficiency + auto-close.
Java
BufferedReader / BufferedWriter
For large files or line-oriented protocols, wrap a Reader/Writer in `Buffered*`. Reduces per-call overhead from many small reads to fewer large ones. Always close with try-with-resources.
Kotlin
Read a File — Whole, Lines, or Stream
Stdlib extensions on `java.io.File` and `java.nio.file.Path`. Use `readText()` for small files, `useLines { }` for memory-efficient line-by-line.
Kotlin
use { } — Auto-Close Resources
`use { }` calls `close()` on any `Closeable` (file, stream, JDBC connection, …) when the block exits — even on exception. Kotlin's try-with-resources.