Checking something about Tokio Semaphores

tokiosemaphoretest/Cargo.lock

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tokiosemaphoretest/Cargo.toml

@@ -0,0 +1,7 @@
+[package]
+name = "tokiosemaphoretest"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+tokio = { version = "1.37.0", features = ["rt", "rt-multi-thread", "macros", "sync"] }

tokiosemaphoretest/src/main.rs

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+use tokio::sync::Semaphore;
+
+#[tokio::main]
+async fn main() {
+    let sem = Semaphore::new(4);
+
+    let _p = sem.acquire_many(3).await;
+    println!("P acquired: {_p:?}");
+
+    // this locks :(
+    let _q = sem.acquire_many(12).await;
+    println!("12 acquired: {_q:?}");
+}