Standard I/O module -- read/write access to stdin, stdout, and stderr.

Provides both synchronous (blocking) and asynchronous (yielding) APIs for interacting with the process's standard streams.

Quick start

local stdio = require("@eryx/stdio")

-- Prompt the user
stdio.write("Enter your name: ")
stdio.flush()
local name = stdio.readln()
stdio.write("Hello, " .. (name or "stranger") .. "!\n")

-- Write to stderr
stdio.writeerr("warning: something happened\n")

-- Check if running in a terminal
local tty = stdio.isatty()
if tty.stdin then
    print("stdin is a terminal")
end

Summary

Functions

API Reference

Functions

stdio.read

Reads up to bytes bytes from stdin (default 4096). Returns nil on EOF.

stdio.read(bytes: number?) → string?

stdio.readline

Reads one line from stdin, stripping the trailing newline. Returns nil on EOF.

stdio.readline() → string?

stdio.write

Writes a string to stdout.

stdio.write(data: string) → ()

stdio.writeerr

Writes a string to stderr.

stdio.writeerr(data: string) → ()

stdio.flush

Flushes the stdout buffer.

stdio.flush() → ()

stdio.flusherr

Flushes the stderr buffer.

stdio.flusherr() → ()

stdio.readasync

Yields the current coroutine until data is available on stdin, then returns up to bytes bytes (default 4096). Returns nil on EOF. Only one readasync may be pending at a time.

stdio.readasync(bytes: number?) → string?

stdio.isatty

Returns a table indicating whether each standard stream is connected to a terminal (TTY).

stdio.isatty() → TtyInfo

Types

TtyInfo

Result of isatty() -- indicates which streams are connected to a terminal.

stdin: boolean

stdout: boolean

stderr: boolean