Add lchown unsupported implementation for vxworks

Author: B I Mohammed Abbas

library/std/src/os/unix/fs.rs

@@ -1040,7 +1040,6 @@ pub fn fchown<F: AsFd>(fd: F, uid: Option<u32>, gid: Option<u32>) -> io::Result<
 /// }
 /// ```
 #[stable(feature = "unix_chown", since = "1.73.0")]
-#[cfg(not(any(target_os = "vxworks")))]
 pub fn lchown<P: AsRef<Path>>(dir: P, uid: Option<u32>, gid: Option<u32>) -> io::Result<()> {
     sys::fs::lchown(dir.as_ref(), uid.unwrap_or(u32::MAX), gid.unwrap_or(u32::MAX))
 }

library/std/src/sys/pal/unix/fs.rs

@@ -1337,7 +1337,7 @@ impl File {
                 // Redox doesn't appear to support `UTIME_OMIT`.
                 // ESP-IDF and HorizonOS do not support `futimens` at all and the behavior for those OS is therefore
                 // the same as for Redox.
-                // `futimens` and `UTIME_OMIT` are a work in progress for vxworks. 
+                // `futimens` and `UTIME_OMIT` are a work in progress for vxworks.
                 let _ = times;
                 Err(io::const_io_error!(
                     io::ErrorKind::Unsupported,
@@ -1969,14 +1969,20 @@ pub fn fchown(fd: c_int, uid: u32, gid: u32) -> io::Result<()> {
     Ok(())
 }
 
-#[cfg(not(any(target_os = "vxworks")))]
+#[cfg(not(target_os = "vxworks"))]
 pub fn lchown(path: &Path, uid: u32, gid: u32) -> io::Result<()> {
     run_path_with_cstr(path, &|path| {
         cvt(unsafe { libc::lchown(path.as_ptr(), uid as libc::uid_t, gid as libc::gid_t) })
             .map(|_| ())
     })
 }
 
+#[cfg(target_os = "vxworks")]
+pub fn lchown(path: &Path, uid: u32, gid: u32) -> io::Result<()> {
+    let (_, _, _) = (path, uid, gid);
+    Err(io::const_io_error!(io::ErrorKind::Unsupported, "lchown not supported by vxworks",))
+}
+
 #[cfg(not(any(target_os = "fuchsia", target_os = "vxworks")))]
 pub fn chroot(dir: &Path) -> io::Result<()> {
     run_path_with_cstr(dir, &|dir| cvt(unsafe { libc::chroot(dir.as_ptr()) }).map(|_| ()))