When stdin is a terminal, for_byte_record_with_terminator() does not exit immediately on Control-D

[zhitkoff]

if stdin().is_terminal() {
        let mut buf_in = BufReader::new(stdin());
        let separator = b'\n';

        println!("Start terminal input for bstr for_byte_record_with_terminator\nTry ^D - it will not exit right away on the first ^D");
        let _result_bstr = buf_in.for_byte_record_with_terminator(separator, |_line| {
            // do something with each line
            Ok(true)
        })?;
        println!("Done");

        println!("Start terminal input for std io, like split, read_until, etc\nTry ^D");
        let _result_std = buf_in.split(separator).for_each(|_line| {
            // do something with each line
        });
        println!("Done");
    }

Comparing to similar functions from std::io, which do exit on the first Control-D right away in the terminal.
This limits usefulness of bstr crate for developing command line utilities that need to process all stdin variants (piped, redirected from file, terminal)

[BurntSushi]

Please provide a full program and an example invocation on the CLI that reproduces the problem. Please include actual output and expected output.

[zhitkoff]

Full program for bstr use case:

use bstr::io::BufReadExt;
use std::io::{self, stdin, BufReader, IsTerminal};

fn main() -> io::Result<()> {
    if stdin().is_terminal() {
        let mut buf_in = BufReader::new(stdin());
        let separator = b'\n';

        println!("Start terminal input for bstr for_byte_record_with_terminator\nTry ^D - it will not exit right away on the first ^D");
        let _result_bstr = buf_in.for_byte_record_with_terminator(separator, |_line| {
            // do something with line
            Ok(true)
        })?;
        println!("Done");
    }
    Ok(())
}

Run with cargo run and it will wait for user input in the terminal. Try ^D (Control-D) and notice that it does not exit, still accepting input in the terminal. Try ^D twice - it should exit to command prompt

[zhitkoff]

Full program to illustrate that using std::io functions in the same scenario does exit on the first ^D:

use std::io::{self, stdin, BufRead, BufReader, IsTerminal};

fn main() -> io::Result<()> {
    if stdin().is_terminal() {
        let buf_in = BufReader::new(stdin());
        let separator = b'\n';

        println!("Start terminal input for std io, like split, read_until, etc\nTry ^D");
        let _result_std = buf_in.split(separator).for_each(|_line| {
            // do something with line
        });
        println!("Done");
    }
    Ok(())
}

Run with cargo run and it will wait for user input in the terminal. Try ^D (Control-D) once and notice that it does exit into command prompt right away.

[BurntSushi]

Nice find. This is fixed in bstr 1.9.1.