A node that forwards messages in a first-in first-out (FIFO) order.

// Defined in header <oneapi/tbb/flow_graph.h>

namespace oneapi {
namespace tbb {
namespace flow {

    template <typename T >
    class queue_node : public graph_node, public receiver<T>, public sender<T> {
        explicit queue_node( graph &g );
        queue_node( const queue_node &src );

        bool try_put( const T &v );
        bool try_get( T &v );

} // namespace flow
} // namespace tbb
} // namespace oneapi


  • The type T must meet the CopyConstructible requirements from [copyconstructible] and CopyAssignable requirements from [copyassignable] ISO C++ Standard sections.

queue_node forwards messages in a FIFO order to a single successor in its successor set.

queue_node is a graph_node, receiver and sender.

queue_node has a buffering and single-push properties.

Member functions#

explicit queue_node(graph &g)#

Constructs an empty queue_node that belongs to the graph g.

queue_node(const queue_node &src)#

Constructs an empty queue_node that belongs to the same graph g as src. Any intermediate state of src, including its links to predecessors and successors, is not copied.

bool try_put(const T &v)#

Adds v to the set of items managed by the node, and tries forwarding the least recently added item to a successor.

Returns: true.

bool try_get(T &v)#

Returns: true if an item can be taken from the node and assigned to v. Returns false if there is no item currently in the queue_node or if the node is reserved.


Usage scenario is similar to buffer_node except that messages are passed in first-in first-out (FIFO) order.