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::c; |
12 | use backend::fd::{BorrowedFd, RawFd}; |
13 | |
14 | /// `AT_FDCWD`—A handle representing the current working directory. |
15 | /// |
16 | /// This is a file descriptor which refers to the process current directory |
17 | /// which can be used as the directory argument in `*at` functions such as |
18 | /// [`openat`]. |
19 | /// |
20 | /// # References |
21 | /// - [POSIX] |
22 | /// |
23 | /// [`openat`]: crate::fs::openat |
24 | /// [POSIX]: https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/fcntl.h.html |
25 | // SAFETY: `AT_FDCWD` is a reserved value that is never dynamically |
26 | // allocated, so it'll remain valid for the duration of `'static`. |
27 | #[doc (alias = "AT_FDCWD" )] |
28 | pub const CWD: BorrowedFd<'static> = |
29 | unsafe { BorrowedFd::<'static>::borrow_raw(fd:c::AT_FDCWD as RawFd) }; |
30 | |
31 | /// Return the value of [`CWD`]. |
32 | #[deprecated (note = "Use `CWD` in place of `cwd()`." )] |
33 | pub const fn cwd() -> BorrowedFd<'static> { |
34 | let at_fdcwd: i32 = c::AT_FDCWD as RawFd; |
35 | |
36 | // SAFETY: `AT_FDCWD` is a reserved value that is never dynamically |
37 | // allocated, so it'll remain valid for the duration of `'static`. |
38 | unsafe { BorrowedFd::<'static>::borrow_raw(fd:at_fdcwd) } |
39 | } |
40 | |