diff --git a/capi/src/io.rs b/capi/src/io.rs
index 7c853015..3a3e242b 100644
--- a/capi/src/io.rs
+++ b/capi/src/io.rs
@@ -284,6 +284,16 @@ pub unsafe extern "C" fn chewing_Reset(ctx: *mut ChewingContext) -> c_int {
     OK
 }
 
+/// # Safety
+///
+/// This function should be called with valid pointers.
+#[no_mangle]
+pub unsafe extern "C" fn chewing_ack(ctx: *mut ChewingContext) -> c_int {
+    let ctx = as_mut_or_return!(ctx, ERROR);
+    ctx.editor.ack();
+    OK
+}
+
 /// # Safety
 ///
 /// This function should be called with valid pointers.
diff --git a/capi/src/lib.rs b/capi/src/lib.rs
index b6f06432..31981e74 100644
--- a/capi/src/lib.rs
+++ b/capi/src/lib.rs
@@ -824,6 +824,17 @@ pub mod output {
     /// This function fails if the IM editor is not in entering state.
     pub use super::io::chewing_clean_bopomofo_buf;
 
+    /// Acknowledge the commit buffer and aux output buffer.
+    ///
+    /// Chewing automatically acknowledges and clear the output buffers after
+    /// processing new input events.
+    ///
+    /// After handling the ephemeral output buffer like the commit buffer and
+    /// the aux output buffer, IM wrappers can proactively acknowledge and clear
+    /// the buffers. This can be used so that IM wrappers don't have to remember
+    /// whether an output has been handled or not.
+    pub use super::io::chewing_ack;
+
     pub use super::public::IntervalType;
 }
 
diff --git a/capi/src/symbols-elf.map b/capi/src/symbols-elf.map
index b60033c3..41bec920 100644
--- a/capi/src/symbols-elf.map
+++ b/capi/src/symbols-elf.map
@@ -123,6 +123,7 @@ CHEWING_0.5 {
 
 CHEWING_0.9 {
     global:
+        chewing_ack;
         chewing_config_has_option;
         chewing_config_set_int;
         chewing_config_get_int;
diff --git a/capi/src/symbols-mach_o.map b/capi/src/symbols-mach_o.map
index d5ae7f5c..374e149a 100644
--- a/capi/src/symbols-mach_o.map
+++ b/capi/src/symbols-mach_o.map
@@ -116,6 +116,7 @@ _chewing_userphrase_lookup
 _chewing_userphrase_remove
 _chewing_zuin_Check
 _chewing_zuin_String
+_chewing_ack
 _chewing_config_has_option
 _chewing_config_set_int
 _chewing_config_get_int
diff --git a/capi/src/symbols-msvc.def b/capi/src/symbols-msvc.def
index 230e20cc..3e75d062 100644
--- a/capi/src/symbols-msvc.def
+++ b/capi/src/symbols-msvc.def
@@ -117,6 +117,7 @@ EXPORTS
     chewing_userphrase_remove;
     chewing_zuin_Check;
     chewing_zuin_String;
+    chewing_ack;
     chewing_config_has_option;
     chewing_config_set_int;
     chewing_config_get_int;
diff --git a/include/chewing.h b/include/chewing.h
index b25591fd..2accffa2 100644
--- a/include/chewing.h
+++ b/include/chewing.h
@@ -248,6 +248,13 @@ void chewing_free(void *ptr);
  */
 int chewing_Reset(struct ChewingContext *ctx);
 
+/**
+ * # Safety
+ *
+ * This function should be called with valid pointers.
+ */
+int chewing_ack(struct ChewingContext *ctx);
+
 /**
  * # Safety
  *
diff --git a/src/editor/mod.rs b/src/editor/mod.rs
index 5128bd6f..9d611220 100644
--- a/src/editor/mod.rs
+++ b/src/editor/mod.rs
@@ -241,6 +241,10 @@ impl Editor {
         self.state = Box::new(Entering);
         self.shared.clear();
     }
+    pub fn ack(&mut self) {
+        self.shared.notice_buffer.clear();
+        self.shared.commit_buffer.clear();
+    }
     pub fn clear_syllable_editor(&mut self) {
         self.shared.syl.clear();
     }
diff --git a/tests/test-bopomofo.c b/tests/test-bopomofo.c
index 2fa7cd2b..daabf0ff 100644
--- a/tests/test-bopomofo.c
+++ b/tests/test-bopomofo.c
@@ -1424,6 +1424,22 @@ void test_SimpleEngine()
     chewing_delete(ctx);
 }
 
+void test_Acknowledge()
+{
+    ChewingContext *ctx;
+
+    ctx = chewing_new();
+    start_testcase(ctx, fd);
+
+    type_keystroke_by_string(ctx, "hk4g4<E>");
+    ok_commit_buffer(ctx, "測試");
+
+    chewing_ack(ctx);
+    ok_commit_buffer(ctx, "");
+
+    chewing_delete(ctx);
+}
+
 void test_get_phoneSeq()
 {
     static const struct {
@@ -2442,6 +2458,7 @@ int main(int argc, char *argv[])
     test_FuzzySearchMode();
     test_FuzzySearchMode_Hanyu();
     test_SimpleEngine();
+    test_Acknowledge();
 
     test_get_phoneSeq();
     test_bopomofo_buffer();