diff --git a/src/bin/clone.rs b/src/bin/clone.rs
index 2854b77e5a..779151ad73 100644
--- a/src/bin/clone.rs
+++ b/src/bin/clone.rs
@@ -115,13 +115,18 @@ fn main() {
     let size_old = fs_old.header.size();
     let free_old = fs_old.allocator().free() * redoxfs::BLOCK_SIZE;
     let used_old = size_old - free_old;
-    match clone(&mut fs_old, &mut fs, |used| {
-        eprint!(
-            "{}%: {} MB/{} MB\r",
-            (used * 100) / used_old,
-            used / 1000 / 1000,
-            used_old / 1000 / 1000
-        );
+    let mut last_percent = 0;
+    match clone(&mut fs_old, &mut fs, move |used| {
+        let percent = (used * 100) / used_old;
+        if percent != last_percent {
+            eprint!(
+                "{}%: {} MB/{} MB\r",
+                percent,
+                used / 1000 / 1000,
+                used_old / 1000 / 1000
+            );
+            last_percent = percent;
+        }
     }) {
         Ok(()) => (),
         Err(err) => {
diff --git a/src/clone.rs b/src/clone.rs
index 5d3c85ea28..3629db6916 100644
--- a/src/clone.rs
+++ b/src/clone.rs
@@ -10,13 +10,13 @@ fn syscall_err(err: syscall::Error) -> io::Error {
 }
 
 //TODO: handle hard links
-pub fn clone_at<D: Disk, E: Disk, F: Fn(u64)>(
+fn clone_at<D: Disk, E: Disk, F: FnMut(u64)>(
     tx_old: &mut Transaction<D>,
     parent_ptr_old: TreePtr<Node>,
     fs: &mut FileSystem<E>,
     parent_ptr: TreePtr<Node>,
     buf: &mut [u8],
-    progress: &F,
+    progress: &mut F,
 ) -> syscall::Result<()> {
     let mut entries = Vec::new();
     tx_old.child_nodes(parent_ptr_old, &mut entries)?;
@@ -66,10 +66,10 @@ pub fn clone_at<D: Disk, E: Disk, F: Fn(u64)>(
     Ok(())
 }
 
-pub fn clone<D: Disk, E: Disk, F: Fn(u64)>(
+pub fn clone<D: Disk, E: Disk, F: FnMut(u64)>(
     fs_old: &mut FileSystem<D>,
     fs: &mut FileSystem<E>,
-    progress: F,
+    mut progress: F,
 ) -> syscall::Result<()> {
     fs_old.tx(|tx_old| {
         // Clone at root node
@@ -80,7 +80,7 @@ pub fn clone<D: Disk, E: Disk, F: Fn(u64)>(
             fs,
             TreePtr::root(),
             &mut buf,
-            &progress,
+            &mut progress,
         )?;
 
         fs.tx(|tx| {
diff --git a/src/lib.rs b/src/lib.rs
index 1f50fa976f..82b9c01f4c 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -28,7 +28,7 @@ pub use self::block::{
     BlockAddr, BlockData, BlockLevel, BlockList, BlockMeta, BlockPtr, BlockRaw, BlockTrait,
 };
 #[cfg(feature = "std")]
-pub use self::clone::{clone, clone_at};
+pub use self::clone::clone;
 pub use self::dir::{DirEntry, DirList};
 pub use self::disk::*;
 pub use self::filesystem::FileSystem;