queue_node¶
[flow_graph.queue_node]
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> {
public:
explicit queue_node( graph &g );
queue_node( const queue_node &src );
~queue_node();
bool try_put( const T &v );
bool try_get( T &v );
};
} // namespace flow
} // namespace tbb
} // namespace oneapi
Requirements:
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¶
-
queue_node(const queue_node &src)¶
Constructs an empty
queue_node
that belongs to the same graphg
assrc
. Any intermediate state ofsrc
, 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 tov
. Returnsfalse
if there is no item currently in thequeue_node
or if the node is reserved.
Example¶
Usage scenario is similar to buffer_node except that messages are passed in first-in first-out (FIFO) order.