In non-broadcast mode, connection tags are only used for counting.

src/libipc/circ/elem_def.h

@@ -74,6 +74,10 @@ public:
         return this->cc_.fetch_and(~cc_id, std::memory_order_acq_rel) & ~cc_id;
     }
 
+    bool connected(cc_t cc_id) const noexcept {
+        return (this->connections() & cc_id) != 0;
+    }
+
     std::size_t conn_count(std::memory_order order = std::memory_order_acquire) const noexcept {
         cc_t cur = this->cc_.load(order);
         cc_t cnt; // accumulates the total bits set in cc
@@ -100,6 +104,11 @@ public:
         }
     }
 
+    bool connected(cc_t cc_id) const noexcept {
+        // In non-broadcast mode, connection tags are only used for counting.
+        return (this->connections() != 0) && (cc_id != 0);
+    }
+
     std::size_t conn_count(std::memory_order order = std::memory_order_acquire) const noexcept {
         return this->connections(order);
     }

src/libipc/ipc.cpp

@@ -628,7 +628,7 @@ static ipc::buff_t recv(ipc::handle_t h, std::uint64_t tm) {
         // pop a new message
         typename queue_t::value_t msg {};
         if (!wait_for(inf->rd_waiter_, [que, &msg, &h] {
-                if (!que->connected(que->elems())) {
+                if (!que->connected()) {
                     reconnect(&h, true);
                 }
                 return !que->pop(msg);

src/libipc/queue.h

@@ -63,13 +63,9 @@ public:
         shm::handle::clear_storage(name);
     }
 
-    bool connected() const noexcept {
-        return connected_ != 0;
-    }
-
     template <typename Elems>
-    bool connected(Elems* elems) noexcept {
-        return connected_ & elems->connections();
+    bool connected(Elems* elems) const noexcept {
+        return elems->connected(connected_);
     }
 
     circ::cc_t connected_id() const noexcept {
@@ -155,6 +151,10 @@ public:
         elems_->disconnect_sender();
     }
 
+    bool connected() const noexcept {
+        return base_t::connected(elems_);
+    }
+
     bool connect() noexcept {
         auto tp = base_t::connect(elems_);
         if (std::get<0>(tp) && std::get<1>(tp)) {