fern 0.5.7

Simple, efficient logging
Documentation 
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extern crate fern;
#[macro_use]
extern crate log;
extern crate syslog;

fn setup_logging() -> Result<(), Box<std::error::Error>> {
    let syslog_fmt = syslog::Formatter3164 {
        facility: syslog::Facility::LOG_USER,
        hostname: None,
        process: "fern-syslog-example".into(),
        pid: 0,
    };
    fern::Dispatch::new()
        // by default only accept warning messages so as not to spam
        .level(log::LevelFilter::Warn)
        // but accept Info if we explicitly mention it
        .level_for("explicit-syslog", log::LevelFilter::Info)
        .chain(syslog::unix(syslog_fmt)?)
        .apply()?;

    Ok(())
}

fn main() {
    setup_logging().expect("failed to initialize logging.");

    // None of this will be shown in the syslog:
    for i in 0..5 {
        info!("executing section: {}", i);

        debug!("section {} 1/4 complete.", i);

        debug!("section {} 1/2 complete.", i);

        debug!("section {} 3/4 complete.", i);

        info!("section {} completed!", i);
    }

    // these two *will* show.

    info!(target: "explicit-syslog", "hello to the syslog! this is rust.");

    warn!("AHHH something's on fire.");
}