&action=edit)  
[ <signal.h> ](/w/cpp/header/csignal "cpp/header/csignal") |  Behaves as if each name from [ ` <csignal> ` ](/w/cpp/header/csignal "cpp/header/csignal") is placed in global namespace  [ [edit] ](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_signal.h&action=edit)  
[ <stdarg.h> ](/w/cpp/header/cstdarg "cpp/header/cstdarg") |  Behaves as if each name from [ ` <cstdarg> ` ](/w/cpp/header/cstdarg "cpp/header/cstdarg") is placed in global namespace  [ [edit] ](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_stdarg.h&action=edit)  
[ <stddef.h> ](/w/cpp/header/cstddef "cpp/header/cstddef") |  Behaves as if each name from [ ` <cstddef> ` ](/w/cpp/header/cstddef "cpp/header/cstddef") is placed in global namespace,   
except for names of [ ` std::byte ` and related functions ](/w/cpp/types/byte
"cpp/types/byte") [ [edit]
](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_stddef.h&action=edit)  
[ <stdint.h> ](/w/cpp/header/cstdint "cpp/header/cstdint") (C++11)  |  Behaves as if each name from [ ` <cstdint> ` ](/w/cpp/header/cstdint "cpp/header/cstdint") is placed in global namespace  [ [edit] ](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_stdint.h&action=edit)  
[ <stdio.h> ](/w/cpp/header/cstdio "cpp/header/cstdio") |  Behaves as if each name from [ ` <cstdio> ` ](/w/cpp/header/cstdio "cpp/header/cstdio") is placed in global namespace  [ [edit] ](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_stdio.h&action=edit)  
[ <stdlib.h> ](/w/cpp/header/cstdlib "cpp/header/cstdlib") |  Behaves as if each name from [ ` <cstdlib> ` ](/w/cpp/header/cstdlib "cpp/header/cstdlib") is placed in global namespace  [ [edit] ](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_stdlib.h&action=edit)  
[ <string.h> ](/w/cpp/header/cstring "cpp/header/cstring") |  Behaves as if each name from [ ` <cstring> ` ](/w/cpp/header/cstring "cpp/header/cstring") is placed in global namespace  [ [edit] ](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_string.h&action=edit)  
[ <time.h> ](/w/cpp/header/ctime "cpp/header/ctime") |  Behaves as if each name from [ ` <ctime> ` ](/w/cpp/header/ctime "cpp/header/ctime") is placed in global namespace  [ [edit] ](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_time.h&action=edit)  
[ <uchar.h> ](/w/cpp/header/cuchar "cpp/header/cuchar") (C++11)  |  Behaves as if each name from [ ` <cuchar> ` ](/w/cpp/header/cuchar "cpp/header/cuchar") is placed in global namespace  [ [edit] ](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_uchar.h&action=edit)  
[ <wchar.h> ](/w/cpp/header/cwchar "cpp/header/cwchar") |  Behaves as if each name from [ ` <cwchar> ` ](/w/cpp/header/cwchar "cpp/header/cwchar") is placed in global namespace  [ [edit] ](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_wchar.h&action=edit)  
[ <wctype.h> ](/w/cpp/header/cwctype "cpp/header/cwctype") |  Behaves as if each name from [ ` <cwctype> ` ](/w/cpp/header/cwctype "cpp/header/cwctype") is placed in global namespace  [ [edit] ](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/header/dsc_wctype.h&action=edit)  
  
####  [ [ edit ](/mwiki/index.php?title=cpp/header&action=edit&section=2 "Edit
section: Special C compatibility headers") ]  Special C compatibility headers

The header [ ` <stdatomic.h> ` ](/w/c/thread#Atomic_operations "c/thread")
declares names which are also provided in the C standard library, and defines
the ` _Atomic ` macro which is a [ keyword ](/w/c/keyword/_Atomic "c/keyword/
Atomic") in C. Unlike other ` _xxx_ .h ` headers, corresponding ` <cstdatomic>
` is not provided.

[ <stdatomic.h> ](/w/cpp/header/stdatomic.h "cpp/header/stdatomic.h") (C++23)  |  Defines ` _Atomic ` and provides corresponding components in the C standard library  [ [edit] ](https://en