diff --git a/src/uu/stdbuf/src/stdbuf.rs b/src/uu/stdbuf/src/stdbuf.rs
index fc51ee6f7..85dddbddd 100644
--- a/src/uu/stdbuf/src/stdbuf.rs
+++ b/src/uu/stdbuf/src/stdbuf.rs
@@ -152,8 +152,8 @@ pub fn uumain(args: impl uucore::Args) -> UResult<()> {
     let mut command = process::Command::new(command_values.next().unwrap());
     let command_params: Vec<&str> = command_values.map(|s| s.as_ref()).collect();
 
-    let mut tmp_dir = tempdir().unwrap();
-    let (preload_env, libstdbuf) = get_preload_env(&mut tmp_dir).map_err_context(String::new)?;
+    let tmp_dir = tempdir().unwrap();
+    let (preload_env, libstdbuf) = get_preload_env(&tmp_dir).map_err_context(String::new)?;
     command.env(preload_env, libstdbuf);
     set_command_env(&mut command, "_STDBUF_I", &options.stdin);
     set_command_env(&mut command, "_STDBUF_O", &options.stdout);