std::ptr::write_unaligned - Rust
Description: API documentation for the Rust `write_unaligned` fn in crate `std`.
Keywords: rust, rustlang, rust-lang, write_unaligned

# Function std::ptr::write_unaligned 1.17.0[−][src]

    pub unsafe fn write_unaligned<T>(dst: *mut T, src: T)

Overwrites a memory location with the given value without reading or dropping the old value.

Unlike `write`, the pointer may be unaligned.

# Safety

This operation is marked unsafe because it accepts a raw pointer.

It does not drop the contents of `dst`. This is safe, but it could leak allocations or resources, so care must be taken not to overwrite an object that should be dropped.

Additionally, it does not drop `src`. Semantically, `src` is moved into the location pointed to by `dst`.

This is appropriate for initializing uninitialized memory, or overwriting memory that has previously been `read` from.

# Examples

Basic usage:

    let mut x = 0;
    let y = &mut x as *mut i32;
    let z = 12;

    unsafe {
        std::ptr::write_unaligned(y, z);
        assert_eq!(std::ptr::read_unaligned(y), 12);
    }Run

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