xref: /third_party/rust/crates/rustix/src/mm/msync.rs (revision b8a62b91)
1//! The `msync` function.
2//!
3//! # Safety
4//!
5//! `msync` operates on a raw pointer. Some forms of `msync` may mutate the
6//! memory or have other side effects.
7#![allow(unsafe_code)]
8
9use crate::{backend, io};
10use core::ffi::c_void;
11
12pub use backend::mm::types::MsyncFlags;
13
14/// `msync(addr, len, flags)`—Synchronizes a memory-mapping with its backing
15/// storage.
16///
17/// # Safety
18///
19/// `addr` must be a valid pointer to memory that is appropriate to
20/// call `msync` on. Some forms of `msync` may mutate the memory
21/// or evoke a variety of side-effects on the mapping and/or the file.
22///
23/// # References
24///  - [POSIX]
25///  - [Linux `msync`]
26///
27/// [POSIX]: https://pubs.opengroup.org/onlinepubs/9699919799/functions/msync.html
28/// [Linux `msync`]: https://man7.org/linux/man-pages/man2/msync.2.html
29#[inline]
30pub unsafe fn msync(addr: *mut c_void, len: usize, flags: MsyncFlags) -> io::Result<()> {
31    backend::mm::syscalls::msync(addr, len, flags)
32}
33