are you or are you not a tty?

Api documentation

extern crate atty;

use atty::Stream;

fn main() {
  if atty::is(Stream::Stdout) {
    println!("I'm a terminal");
  } else {
    println!("I'm not");
  }
}

Add the following to your Cargo.toml

[dependencies]
atty = "0.2"

This library has been unit tested on both unix and windows platforms (via appveyor).

A simple example program is provided in this repo to test various tty's. By default.

It prints

$ cargo run --example atty
stdout? true
stderr? true
stdin? true

To test std in, pipe some text to the program

$ echo "test" | cargo run --example atty
stdout? true
stderr? true
stdin? false

To test std out, pipe the program to something

$ cargo run --example atty | grep std
stdout? false
stderr? true
stdin? true

To test std err, pipe the program to something redirecting std err

$ cargo run --example atty 2>&1 | grep std
stdout? false
stderr? false
stdin? true

Doug Tangren (softprops) 2015