It felt like a long time ago when Felix and I built the terminal todo list tdo. But now there was time to build something new!
We started to rewrite this project in Rust a while ago, but in between I had no time to practice this language at all. So I tried to teach myself again on a different project. A notifier should be good. I want to get a mail with all my tasks.

This idea was the beginning of tdo-notify a tool that can be run in a cronjob to notify you every day. Because of the similarity between Rust and Swift it was a bit tricky to remember the correct syntax and I had some problems with the borrow checker. All in all after reading tons of documentations of the different crates there was a version that worked. But there was nothing personal in it. Just the tasks, no initial sentence.

How do you get the full name of the current user? It would be nice, if you have a greeting in that mail!
Well, you could use finger `whoami` to get the user information. The only thing is, that I don’t want to spawn a subprocess.
There is another method: using libc.

It took me hours to get a satisfying result and I ended up with the following piece of code:

extern crate libc;
use std::{slice, io, ptr};

fn get_user_name() -> Result<String, io::Error> {
    unsafe {
        let uid = libc::geteuid();
        let user = ptr::read(libc::getpwuid(uid));
        let name = String::from_utf8_unchecked(slice::from_raw_parts(user.pw_gecos as *const u8,
                                                           libc::strlen(user.pw_gecos) as usize)
                .to_vec());
        if name == "" {
            Err(io::Error::last_os_error())
        } else {
            Ok(name)
        }
    }
}