1 | //! The `cwd` function, representing the current working directory. |
2 | //! |
3 | //! # Safety |
4 | //! |
5 | //! This file uses `AT_FDCWD`, which is a raw file descriptor, but which is |
6 | //! always valid. |
7 | |
8 | #![allow (unsafe_code)] |
9 | |
10 | use crate::backend; |
11 | use backend::fd::{BorrowedFd, RawFd}; |
12 | |
13 | /// `AT_FDCWD`—Returns a handle representing the current working directory. |
14 | /// |
15 | /// This returns a file descriptor which refers to the process current |
16 | /// directory which can be used as the directory argument in `*at` |
17 | /// functions such as [`openat`]. |
18 | /// |
19 | /// # References |
20 | /// - [POSIX] |
21 | /// |
22 | /// [`openat`]: crate::fs::openat |
23 | /// [POSIX]: https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/fcntl.h.html |
24 | #[inline ] |
25 | #[doc (alias = "AT_FDCWD" )] |
26 | pub const fn cwd() -> BorrowedFd<'static> { |
27 | let at_fdcwd: i32 = backend::io::types::AT_FDCWD as RawFd; |
28 | |
29 | // SAFETY: `AT_FDCWD` is a reserved value that is never dynamically |
30 | // allocated, so it'll remain valid for the duration of `'static`. |
31 | unsafe { BorrowedFd::<'static>::borrow_raw(fd:at_fdcwd) } |
32 | } |
33 | |