From bcaac146d2516bb75c2ea78b26e03b12c7c7f61e Mon Sep 17 00:00:00 2001
From: Levi Neely <lneely@pascom.net>
Date: Thu, 13 Aug 2026 20:59:05 +0200
Subject: [PATCH] server: on BlockOnce timeout, fall back to non-blocking Read
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Frontends rely on getting the current state on timeout (heartbeat).
When BlockOnce returns empty (5s timeout), the server now calls the
plain Read handler as fallback. Files without a Read handler (like
feed) return nothing — consumer unaffected.
---
 cmd/olliesrv/server.go | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/cmd/olliesrv/server.go b/cmd/olliesrv/server.go
index d5183f9..4a55dec 100644
--- a/cmd/olliesrv/server.go
+++ b/cmd/olliesrv/server.go
@@ -500,6 +500,10 @@ func read(root *fs.Tree, cs *connState, fc *plan9.Fcall, ctx context.Context) *p
 		if err != nil {
 			return errFcall(fc, err.Error())
 		}
+		if len(content) == 0 {
+			// Timeout: fall back to non-blocking Read for current value.
+			content, _ = entry.Read()
+		}
 		if nextBase != "" {
 			cs.mu.Lock()
 			if f, ok := cs.fids[fc.Fid]; ok {