imap: Flush response to client before starting possibly long operation

Fixes Error: Timeout communicating with /var/run/dovecot/imap-master (version received)

diff --git a/src/imap/imap-master-client.c b/src/imap/imap-master-client.c
index 9f311d512ac9c8ca98f186bc7ed058c3e8d99747..e00b4631864e61d3258df14e23a067412e3bc135 100644 (file)
--- a/src/imap/imap-master-client.c
+++ b/src/imap/imap-master-client.c
@@ -217,6 +217,7 @@ imap_master_client_input_args(struct connection *conn, const char *const *args,
           potentially a long time. imap-hibernate process is waiting for us
           to answer. Even if we fail later, we log the error anyway. */
        o_stream_nsend_str(conn->output, "+\n");
+       (void)o_stream_flush(conn->output);
 
        /* NOTE: before client_create_from_input() on failures we need to close
           fd_client, but afterward it gets closed by client_destroy() */