Script to detect whether mosh-server is a parent process

detect-mosh.rs

#!/usr/bin/env rust-script

//! ```cargo
//! [dependencies]
//! anyhow = "1"
//! libc = "0.2"
//! procfs = { version = "0.16", default-features = false }
//! ```

use procfs::process::Process;
use std::ffi::OsStr;

const INIT_PID: libc::pid_t = 1;

#[cfg(target_os = "linux")]
fn main() -> anyhow::Result<std::process::ExitCode> {
    let mosh_server_name: &OsStr = OsStr::new("mosh-server");

    let my_ppid = unsafe { libc::getppid() };
    let mut p = Process::new(my_ppid)?;
    while p.pid != INIT_PID {
        if p.exe()?.file_name() == Some(mosh_server_name) {
            return Ok(0.into());
        }

        p = Process::new(p.status()?.ppid)?;
    }
    return Ok(1.into());
}