Add O_SEARCH to all platforms supported by libc crate (#2374)

* add solarish and freebsd to O_SEARCH, as it exists in in the libc crate

* fcntl/O_SEARCH: add description similiar to the posix manpage

* fcntl O_SEARCH oops - fix syntax

* fcntl O_SEARCH: add fuchsia

* O_SEARCH: changelog

* fcntl/OPath: no alias for single platform

Co-authored-by: SteveLauC <[email protected]>

* O_SEARCH: also add aux, wasi, emscripten

* O_SEARCH: updated added platforms in changelog

---------

Co-authored-by: SteveLauC <[email protected]>

Author: TheJonny

changelog/2374.added.md

@@ -0,0 +1 @@
+Add `open` flag `O_SEARCH` to AIX, Empscripten, FreeBSD, Fuchsia, solarish, WASI

src/fcntl.rs

@@ -164,8 +164,9 @@ libc_bitflags!(
         /// Similar to `O_DSYNC` but applies to `read`s instead.
         #[cfg(any(target_os = "linux", netbsdlike))]
         O_RSYNC;
-        /// Skip search permission checks.
-        #[cfg(target_os = "netbsd")]
+        /// Open directory for search only. Skip search permission checks on
+        /// later `openat()` calls using the obtained file descriptor.
+        #[cfg(any(target_os = "netbsd", target_os = "freebsd", solarish, target_os = "fuchsia", target_os = "emscripten", target_os = "aix", target_os = "wasi"))]
         O_SEARCH;
         /// Open with a shared file lock.
         #[cfg(any(bsd, target_os = "redox"))]