# thread::id

## Summary

Unique identifier for a thread.

## Syntax

    class thread::id;

## Header

    #include "tbb/compat/thread"

## Description

A `thread::id` is an identifier value for a thread that remains unique over the thread's lifetime. A special value `thread::id()` represents no thread of execution. The instances are totally ordered.

## Members

    namespace tbb {
                        class thread::id {
                        public:
                            id();
                        };
                        template<typename charT, typename traits>
                        std::basic_ostream<charT, traits>&
                            operator<< (std::basic_ostream<charT, traits> &out,
                                        thread::id id)

                        bool operator==(thread::id x, thread::id y);
                        bool operator!=(thread::id x, thread::id y);
                        bool operator<(thread::id x, thread::id y);
                        bool operator<=(thread::id x, thread::id y);
                        bool operator>(thread::id x, thread::id y);
                        bool operator>=(thread::id x, thread::id y);
                    } // namespace tbb

Parent topic: Threads