system&action=edit)  
  
###  Regular Expressions library  
  
[ <regex> ](/w/cpp/header/regex "cpp/header/regex") (C++11)  |  [ Classes, algorithms and iterators to support regular expression processing ](/w/cpp/regex "cpp/regex") [ [edit] ](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_regex&action=edit)  
  
###  Atomic Operations library  
  
[ <atomic> ](/w/cpp/header/atomic "cpp/header/atomic") (C++11)  |  [ Atomic operations library ](/w/cpp/thread#Atomic_operations "cpp/thread") [ [edit] ](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_atomic&action=edit)  
  
###  Thread support library  
  
[ <barrier> ](/w/cpp/header/barrier "cpp/header/barrier") (C++20)  |  [ Barriers ](/w/cpp/thread/barrier "cpp/thread/barrier") [ [edit] ](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_barrier&action=edit)  
[ <condition_variable> ](/w/cpp/header/condition_variable "cpp/header/condition variable") (C++11)  |  [ Thread waiting conditions ](/w/cpp/thread "cpp/thread") [ [edit] ](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_condition_variable&action=edit)  
[ <future> ](/w/cpp/header/future "cpp/header/future") (C++11)  |  [ Primitives for asynchronous computations ](/w/cpp/thread "cpp/thread") [ [edit] ](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_future&action=edit)  
[ <hazard_pointer> ](/w/cpp/header/hazard_pointer "cpp/header/hazard pointer") (C++26)  |  Hazard pointers  [ [edit] ](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_hazard_pointer&action=edit)  
[ <latch> ](/w/cpp/header/latch "cpp/header/latch") (C++20)  |  [ Latches ](/w/cpp/thread/latch "cpp/thread/latch") [ [edit] ](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_latch&action=edit)  
[ <mutex> ](/w/cpp/header/mutex "cpp/header/mutex") (C++11)  |  [ Mutual exclusion primitives ](/w/cpp/thread "cpp/thread") [ [edit] ](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_mutex&action=edit)  
[ <rcu> ](/w/cpp/header/rcu "cpp/header/rcu") (C++26)  |  Read-copy update mechanisms  [ [edit] ](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_rcu&action=edit)  
[ <semaphore> ](/w/cpp/header/semaphore "cpp/header/semaphore") (C++20)  |  [ Semaphores ](/w/cpp/thread/counting_semaphore "cpp/thread/counting semaphore") [ [edit] ](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_semaphore&action=edit)  
[ <shared_mutex> ](/w/cpp/header/shared_mutex "cpp/header/shared mutex") (C++14)  |  [ Shared mutual exclusion primitives ](/w/cpp/thread "cpp/thread") [ [edit] ](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_shared_mutex&action=edit)  
[ <stop_token> ](/w/cpp/header/stop_token "cpp/header/stop token") (C++20)  |  Stop tokens for  [ std::jthread ](/w/cpp/thread/jthread "cpp/thread/jthread") [ [edit] ](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_stop_token&action=edit)  
[ <thread> ](/w/cpp/header/thread "cpp/header/thread") (C++11)  |  [ std::thread ](/w/cpp/thread/thread "cpp/thread/thread") class and [ supporting functions ](/w/cpp/thread "cpp/thread") [ [edit] ](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_thread&action=edit)  
  
###  [ [ edit ](/mwiki/index.php?title=cpp/header&action=edit&section=1 "Edit
section: C compatibility headers") ]  C compatibility headers

For some of the C standard library headers of the form ` _xxx_ .h ` , the C++
standard library both includes an identically-named header and another header
of the form ` c _xxx_ ` (all meaningful ` c _xxx_ ` headers are listed above).
The intended use of headers of form ` _xxx_ .h ` is for interoperability only.
It is possible that C++ source files need to include one of these headers in
order to be valid ISO C. Source files that are not intended to also be valid
IS