sysctl 0.1.1

Simplified Rust interface to libc::sysctl
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extern crate sysctl;
extern crate libc;

use libc::c_int;
use std::fmt;

// Copied from /usr/include/sys/time.h
#[derive(Debug)]
#[repr(C)]
struct ClockInfo {
    hz: c_int, /* clock frequency */
    tick: c_int, /* micro-seconds per hz tick */
    spare: c_int,
    stathz: c_int, /* statistics clock frequency */
    profhz: c_int, /* profiling clock frequency */
}

// Copied from /usr/include/sys/resource.h
#[repr(C)]
struct LoadAvg {
    ldavg: [u32; 3],
    fscale: u64,
}
impl fmt::Debug for LoadAvg {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        let s = self.fscale as f32;
        write!(f,
               "LoadAvg {{ {:.2} {:.2} {:.2} }}",
               self.ldavg[0] as f32 / s,
               self.ldavg[1] as f32 / s,
               self.ldavg[2] as f32 / s)
    }
}

fn main() {
    // Generic type to pass to function will be inferred if not specified on RHS
    println!("\nRead sysctl kern.clockrate as struct directly");
    let val: Box<ClockInfo> = sysctl::value_as("kern.clockrate").unwrap();
    println!("{:?}", val);

    // Pass type LoadAvg to generic function
    println!("\nRead sysctl vm.loadavg as struct directly");
    let val = sysctl::value_as::<LoadAvg>("vm.loadavg").unwrap();
    println!("{:?}", val);
}