io.Reader/io.Writer, os and bufio in Go: File Operations, Composing Streams and embed
In Go a file, a gzip stream, an HTTP body and a string all satisfy the same single-method io.Reader; when a function takes an io.Reader instead of a file name, a 1 GB log is processed with constant memory. bufio.Scanner's 64 KB line limit and silent stop, the Close error of a written file, flushing csv.Writer, composition with LimitReader/MultiWriter/TeeReader, and embedding an e-mail template into the binary with //go:embed.
15 Nov 2026
·
12 min
·
5
