diff --git a/lib/write.ml b/lib/write.ml
index 0e2090c9..f098c602 100644
--- a/lib/write.ml
+++ b/lib/write.ml
@@ -441,20 +441,21 @@ let to_channel ?buf ?(len=4096) ?std oc x =
   let ob =
     match buf with
         None -> Buffer.create len
-      | Some ob -> ob
+      | Some ob -> Buffer.clear ob; ob
   in
   to_buffer ?std ob x;
-  Buffer.output_buffer oc ob
+  Buffer.output_buffer oc ob;
+  Buffer.clear ob
 
 let to_output ?buf ?(len=4096) ?std out x =
   let ob =
     match buf with
         None -> Buffer.create len
-      | Some ob -> ob
+      | Some ob -> Buffer.clear ob; ob
   in
   to_buffer ?std ob x;
   out#output (Buffer.contents ob) 0 (Buffer.length ob);
-  ()
+  Buffer.clear ob
 
 let to_file ?len ?std ?(newline = true) file x =
   let oc = open_out file in
@@ -487,7 +488,7 @@ let stream_to_channel ?buf ?(len=2096) ?std oc st =
   let ob =
     match buf with
         None -> Buffer.create len
-      | Some ob -> ob
+      | Some ob -> Buffer.clear ob; ob
   in
   stream_to_buffer ?std ob st
 
diff --git a/lib/write.mli b/lib/write.mli
index 5b77accd..364da593 100644
--- a/lib/write.mli
+++ b/lib/write.mli
@@ -23,13 +23,9 @@ val to_channel :
   ?std:bool ->
   out_channel -> t -> unit
   (** Write a compact JSON value to a channel.
-      @param buf allows to reuse an existing buffer created with
-      [Buffer.create] on the same channel.
-      [buf] is flushed right
-      before [to_channel] returns but the [out_channel] is
-      not flushed automatically.
+      Note: the [out_channel] is not flushed by this function.
 
-      See [to_string] for the role of the other optional arguments. *)
+      See [to_string] for the role of the optional arguments. *)
 
 val to_output :
   ?buf:Buffer.t ->
@@ -37,13 +33,8 @@ val to_output :
   ?std:bool ->
   < output : string -> int -> int -> int; .. > -> t -> unit
   (** Write a compact JSON value to an OO channel.
-      @param buf allows to reuse an existing buffer created with
-      [Buffer.add_channel] on the same channel.
-      [buf] is flushed right
-      before [to_output] returns but the channel itself is
-      not flushed automatically.
 
-      See [to_string] for the role of the other optional arguments. *)
+      See [to_string] for the role of the optional arguments. *)
 
 val to_file :
   ?len:int ->