1 files changed, 2 insertions, 0 deletions
diff --git a/src/ninep/ctl.zig b/src/ninep/ctl.zig
index 1b1288a1..424245eb 100644
--- a/src/ninep/ctl.zig
+++ b/src/ninep/ctl.zig
@@ -660,6 +660,8 @@ pub fn writePane(p: *Pardes, req: Req, pane: *Pane) Reply {
                 if (!held) return tree.failText(req.tag, E.INVAL, e_not_locked);
                 held = false;
                 if (apply) pane.fs.lock = null;
+            } else if (std.mem.eql(u8, line, "answer")) {
+                return tree.failText(req.tag, E.INVAL, "answer takes a choice or -");
             } else if (std.mem.startsWith(u8, line, "answer ")) {
                 // The pane's question (its `ask` in the log), answered.
                 const choice = std.mem.trim(u8, line["answer ".len..], " ");