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Link `Command::current_dir`.

Co-authored-by: Amanieu d'Antras <amanieu@gmail.com>

Author: joshtriplett

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

@@ -202,10 +202,10 @@ pub trait CommandExt: Sealed {
     /// Set the root of the child process. This calls `chroot` in the child process before executing
     /// the command.
     ///
-    /// This happens before changing to the directory specified with `Command::current_dir`, and
+    /// This happens before changing to the directory specified with [`Command::current_dir`], and
     /// that directory will be relative to the new root.
     ///
-    /// If no directory has been specified with `Command::current_dir`, this will set the directory
+    /// If no directory has been specified with [`Command::current_dir`], this will set the directory
     /// to `/`, to avoid leaving the current directory outside the chroot. (This is an intentional
     /// difference from the underlying `chroot` system call.)
     #[unstable(feature = "process_chroot", issue = "141298")]