Struct std::sys_common::thread_local_key::StaticKey

pub struct StaticKey {
    key: AtomicUsize,
    dtor: Option<unsafe extern "C" fn(_: *mut u8)>,
}

🔬This is a nightly-only experimental API. (thread_local_internals)

A type for TLS keys that are statically allocated.

This type is entirely unsafe to use as it does not protect against use-after-deallocation or use-during-deallocation.

The actual OS-TLS key is lazily allocated when this is used for the first time. The key is also deallocated when the Rust runtime exits or destroy is called, whichever comes first.

Examples

use tls::os::{StaticKey, INIT};

// Use a regular global static to store the key.
static KEY: StaticKey = INIT;

// The state provided via `get` and `set` is thread-local.
unsafe {
    assert!(KEY.get().is_null());
    KEY.set(1 as *mut u8);
}

Fields

key: AtomicUsize

🔬This is a nightly-only experimental API. (thread_local_internals)

Inner static TLS key (internals).

dtor: Option<unsafe extern "C" fn(_: *mut u8)>

🔬This is a nightly-only experimental API. (thread_local_internals)

Destructor for the TLS value.

See Key::new for information about when the destructor runs and how it runs.

Implementations

impl StaticKey

pub fn new(dtor: Option<unsafe extern "C" fn(_: *mut u8)>) -> StaticKey

🔬This is a nightly-only experimental API. (thread_local_internals)

pub unsafe fn get(&self) -> *mut u8

🔬This is a nightly-only experimental API. (thread_local_internals)

Gets the value associated with this TLS key

This will lazily allocate a TLS key from the OS if one has not already been allocated.

pub unsafe fn set(&self, val: *mut u8)

🔬This is a nightly-only experimental API. (thread_local_internals)

Sets this TLS key to a new value.

This will lazily allocate a TLS key from the OS if one has not already been allocated.

unsafe fn key(&self) -> pthread_key_t

🔬This is a nightly-only experimental API. (thread_local_internals)

unsafe fn lazy_init(&self) -> usize

🔬This is a nightly-only experimental API. (thread_local_internals)