chuniio-yubideck/vendor/shared_memory/examples/event.rs

37 lines
1.3 KiB
Rust

use raw_sync::{events::*, Timeout};
use shared_memory::*;
fn main() -> Result<(), Box<dyn std::error::Error>> {
env_logger::init();
// Attempt to create a mapping or open if it already exists
println!("Getting the shared memory mapping");
let shmem = match ShmemConf::new().size(4096).flink("event_mapping").create() {
Ok(m) => m,
Err(ShmemError::LinkExists) => ShmemConf::new().flink("event_mapping").open()?,
Err(e) => return Err(Box::new(e)),
};
if shmem.is_owner() {
//Create an event in the shared memory
println!("Creating event in shared memory");
let (evt, used_bytes) = unsafe { Event::new(shmem.as_ptr(), true)? };
println!("\tUsed {} bytes", used_bytes);
println!("Launch another instance of this example to signal the event !");
evt.wait(Timeout::Infinite)?;
println!("\tGot signal !");
} else {
// Open existing event
println!("Openning event from shared memory");
let (evt, used_bytes) = unsafe { Event::from_existing(shmem.as_ptr())? };
println!("\tEvent uses {} bytes", used_bytes);
println!("Signaling event !");
evt.set(EventState::Signaled)?;
println!("\tSignaled !");
}
println!("Done !");
Ok(())
}