Iterating Over a Concurrent Queue for Debugging#
The template classes concurrent_queue and
concurrent_bounded_queue support STL-style iteration. This support
is intended only for debugging, when you need to dump a queue. The
iterators go forwards only, and are too slow to be very useful in
production code. If a queue is modified, all iterators pointing to it
become invalid and unsafe to use. The following snippet dumps a queue.
The operator<< is defined for a Foo.
concurrent_queue<Foo> q;
...
typedef concurrent_queue<Foo>::const_iterator iter;
for(iter i(q.unsafe_begin()); i!=q.unsafe_end(); ++i ) {
cout << *i;
}
The prefix unsafe_ on the methods is a reminder that they are not
concurrency safe.