diff --git a/src/fs/file.rs b/src/fs/file.rs
index c375aab..2966d96 100644
--- a/src/fs/file.rs
+++ b/src/fs/file.rs
@@ -3,42 +3,30 @@
 use std::fs;
 use std::io::Error as IOError;
 use std::io::Result as IOResult;
-use std::os::unix::fs::{MetadataExt, PermissionsExt};
+use std::os::unix::fs::{MetadataExt, PermissionsExt, FileTypeExt};
 use std::path::{Path, PathBuf};
 
 use fs::dir::Dir;
 use fs::fields as f;
 
-#[cfg(any(target_os = "macos", target_os = "linux"))]
-use std::os::unix::fs::FileTypeExt;
 
-
-/// Constant table copied from https://doc.rust-lang.org/src/std/sys/unix/ext/fs.rs.html#11-259
-/// which is currently unstable and lacks vision for stabilization,
-/// see https://github.com/rust-lang/rust/issues/27712
-#[allow(dead_code, non_camel_case_types)]
+#[allow(trivial_numeric_casts)]
 mod modes {
-    pub type mode_t = u32;
+    use libc;
 
-    pub const USER_READ: mode_t = 0o400;
-    pub const USER_WRITE: mode_t = 0o200;
-    pub const USER_EXECUTE: mode_t = 0o100;
-    pub const USER_RWX: mode_t = 0o700;
-    pub const GROUP_READ: mode_t = 0o040;
-    pub const GROUP_WRITE: mode_t = 0o020;
-    pub const GROUP_EXECUTE: mode_t = 0o010;
-    pub const GROUP_RWX: mode_t = 0o070;
-    pub const OTHER_READ: mode_t = 0o004;
-    pub const OTHER_WRITE: mode_t = 0o002;
-    pub const OTHER_EXECUTE: mode_t = 0o001;
-    pub const OTHER_RWX: mode_t = 0o007;
-    pub const ALL_READ: mode_t = 0o444;
-    pub const ALL_WRITE: mode_t = 0o222;
-    pub const ALL_EXECUTE: mode_t = 0o111;
-    pub const ALL_RWX: mode_t = 0o777;
-    pub const SETUID: mode_t = 0o4000;
-    pub const SETGID: mode_t = 0o2000;
-    pub const STICKY_BIT: mode_t = 0o1000;
+    pub type Mode = u32;
+    // The `libc::mode_t` type’s actual type varies, but the value returned
+    // from `metadata.permissions().mode()` is always `u32`.
+
+    pub const USER_READ: Mode     = libc::S_IRUSR as Mode;
+    pub const USER_WRITE: Mode    = libc::S_IWUSR as Mode;
+    pub const USER_EXECUTE: Mode  = libc::S_IXUSR as Mode;
+    pub const GROUP_READ: Mode    = libc::S_IRGRP as Mode;
+    pub const GROUP_WRITE: Mode   = libc::S_IWGRP as Mode;
+    pub const GROUP_EXECUTE: Mode = libc::S_IXGRP as Mode;
+    pub const OTHER_READ: Mode    = libc::S_IROTH as Mode;
+    pub const OTHER_WRITE: Mode   = libc::S_IWOTH as Mode;
+    pub const OTHER_EXECUTE: Mode = libc::S_IXOTH as Mode;
 }
 
 
@@ -149,6 +137,27 @@ impl<'dir> File<'dir> {
         self.metadata.file_type().is_symlink()
     }
 
+    /// Whether this file is a named pipe on the filesystem.
+    pub fn is_pipe(&self) -> bool {
+       self.metadata.file_type().is_fifo()
+   }
+
+   /// Whether this file is a char device on the filesystem.
+   pub fn is_char_device(&self) -> bool {
+       self.metadata.file_type().is_char_device()
+   }
+
+   /// Whether this file is a block device on the filesystem.
+   pub fn is_block_device(&self) -> bool {
+       self.metadata.file_type().is_block_device()
+   }
+
+   /// Whether this file is a socket on the filesystem.
+   pub fn is_socket(&self) -> bool {
+       self.metadata.file_type().is_socket()
+   }
+
+
     /// Whether this file is a dotfile, based on its name. In Unix, file names
     /// beginning with a dot represent system or configuration files, and
     /// should be hidden by default.
@@ -359,52 +368,6 @@ impl<'dir> File<'dir> {
     }
 }
 
-#[cfg(any(target_os = "macos", target_os = "linux"))]
-impl<'dir> File<'dir> {
-    /// Whether this file is a named pipe on the filesystem.
-    pub fn is_pipe(&self) -> bool {
-        self.metadata.file_type().is_fifo()
-    }
-
-    /// Whether this file is a char device on the filesystem.
-    pub fn is_char_device(&self) -> bool {
-        self.metadata.file_type().is_char_device()
-    }
-
-    /// Whether this file is a block device on the filesystem.
-    pub fn is_block_device(&self) -> bool {
-        self.metadata.file_type().is_block_device()
-    }
-
-    /// Whether this file is a socket on the filesystem.
-    pub fn is_socket(&self) -> bool {
-        self.metadata.file_type().is_socket()
-    }
-}
-
-#[cfg(not(any(target_os = "macos", target_os = "linux")))]
-impl<'dir> File<'dir> {
-    /// Whether this file is a named pipe on the filesystem.
-    pub fn is_pipe(&self) -> bool {
-        false
-    }
-
-    /// Whether this file is a char device on the filesystem.
-    pub fn is_char_device(&self) -> bool {
-        false
-    }
-
-    /// Whether this file is a block device on the filesystem.
-    pub fn is_block_device(&self) -> bool {
-        false
-    }
-
-    /// Whether this file is a socket on the filesystem.
-    pub fn is_socket(&self) -> bool {
-        false
-    }
-}
-
 
 impl<'a> AsRef<File<'a>> for File<'a> {
     fn as_ref(&self) -> &File<'a> {