diff --git a/doc/src/sgml/libpq.sgml b/doc/src/sgml/libpq.sgml
new file mode 100644
index de272c5..ad104a3
*** a/doc/src/sgml/libpq.sgml
--- b/doc/src/sgml/libpq.sgml
*************** int PQsetnonblocking(PGconn *conn, int a
*** 4318,4325 ****
        <para>
         In the nonblocking state, calls to
         <function>PQsendQuery</function>, <function>PQputline</function>,
!        <function>PQputnbytes</function>, and
!        <function>PQendcopy</function> will not block but instead return
         an error if they need to be called again.
        </para>
  
--- 4318,4325 ----
        <para>
         In the nonblocking state, calls to
         <function>PQsendQuery</function>, <function>PQputline</function>,
!        <function>PQputnbytes</function>, <function>PQputCopyData</function>,
!        and <function>PQendcopy</function> will not block but instead return
         an error if they need to be called again.
        </para>
  
*************** int PQputCopyData(PGconn *conn,
*** 4961,4969 ****
        <para>
         Transmits the <command>COPY</command> data in the specified
         <parameter>buffer</>, of length <parameter>nbytes</>, to the server.
!        The result is 1 if the data was sent, zero if it was not sent
!        because the attempt would block (this case is only possible if the
!        connection is in nonblocking mode), or -1 if an error occurred.
         (Use <function>PQerrorMessage</function> to retrieve details if
         the return value is -1.  If the value is zero, wait for write-ready
         and try again.)
--- 4961,4969 ----
        <para>
         Transmits the <command>COPY</command> data in the specified
         <parameter>buffer</>, of length <parameter>nbytes</>, to the server.
!        The result is 1 if the data was queued, zero if it was not queued
!        because of full buffers (this will only happen in nonblocking mode),
!        or -1 if an error occurred.
         (Use <function>PQerrorMessage</function> to retrieve details if
         the return value is -1.  If the value is zero, wait for write-ready
         and try again.)
*************** int PQputCopyEnd(PGconn *conn,
*** 5009,5021 ****
         connections.)
        </para>
  
!       <para>
!        The result is 1 if the termination data was sent, zero if it was
!        not sent because the attempt would block (this case is only possible
!        if the connection is in nonblocking mode), or -1 if an error
!        occurred.  (Use <function>PQerrorMessage</function> to retrieve
!        details if the return value is -1.  If the value is zero, wait for
!        write-ready and try again.)
        </para>
  
        <para>
--- 5009,5026 ----
         connections.)
        </para>
  
!       <para> 
!        The result is 1 if the termination message was sent; or in
!        nonblocking mode, this may only indicate that the termination
!        message was successfully queued.  (In nonblocking mode, to be
!        certain that the data has been sent, you should next wait for
!        write-ready and call <function>PQflush</>, repeating until it
!        returns zero.)  Zero indicates that the function could not queue
!        the termination message because of full buffers; this will only
!        happen in nonblocking mode.  (In this case, wait for
!        write-ready and try the <function>PQputCopyEnd</> call
!        again.)  If a hard error occurs, -1 is returned; you can use
!        <function>PQerrorMessage</function> to retrieve details.
        </para>
  
        <para>