Namespaces
Variants
Views
Actions

Standard library header <cstdarg>

From cppreference.com
< cpp‎ | header
 
 
Standard library headers
Language support
<coroutine> (C++20)
<csignal>
<csetjmp>
<cstdarg>

Concepts
<concepts> (C++20)
Diagnostics
<system_error> (C++11)

Memory management
<memory_resource> (C++17)  
Metaprogramming
<type_traits> (C++11)
<ratio> (C++11)
General utilities
<utility>
<tuple> (C++11)
<optional> (C++17)
<variant> (C++17)
<any> (C++17)
<debugging> (C++26)
<expected> (C++23)
<bitset>
<charconv> (C++17)
<format> (C++20)
<bit> (C++20)

Strings
<cuchar> (C++11)

Containers
<flat_set> (C++23)
<span> (C++20)
<mdspan> (C++23)

Iterators
<iterator>
Ranges
<ranges> (C++20)
<generator> (C++23)
Algorithms
Numerics
<cfenv> (C++11)
<complex>
<cmath>
<linalg> (C++26)
<numbers> (C++20)

Time
<chrono> (C++11)
Localization
<codecvt> (C++11/17/26*)
<text_encoding> (C++26)
Input/output
<filesystem> (C++17)
<cstdio>
<cinttypes> (C++11)
<strstream> (C++98*)
Regular expressions
<regex> (C++11)
Concurrency support
<stop_token> (C++20)
<thread> (C++11)
<atomic> (C++11)
<rcu> (C++26)
<stdatomic.h> (C++23)
<mutex> (C++11)
<shared_mutex> (C++14)

<condition_variable> (C++11)  
<semaphore> (C++20)
<latch> (C++20)

<barrier> (C++20)
<future> (C++11)
<hazard_pointer> (C++26)

C compatibility
<cstdbool> (C++11/17/20*)  
<ccomplex> (C++11/17/20*)
<ctgmath> (C++11/17/20*)

<cstdalign> (C++11/17/20*)

<ciso646> (until C++20)

 

This header was originally in the C standard library as <stdarg.h>.

This header provides support for C-style variadic functions, while the C definition of "default argument promotions" is replaced with the C++ definition.

Contents

Types

holds the information needed by va_start, va_arg, va_end, and va_copy
(typedef) [edit]

Macros

enables access to variadic function arguments
(function macro) [edit]
accesses the next variadic function argument
(function macro) [edit]
(C++11)
makes a copy of the variadic function arguments
(function macro) [edit]
ends traversal of the variadic function arguments
(function macro) [edit]

[edit] Synopsis

namespace std {
  using va_list = /*see description*/ ;
}
#define va_arg(V, P) /*see description*/
#define va_copy(VDST, VSRC) /*see description*/
#define va_end(V) /*see description*/
#define va_start(V, P) /*see description*/

[edit] Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR Applied to Behavior as published Correct behavior
CWG 2645 C++98 C++ defines "default argument promotions", but its C definition was used the C++ definition overrides the C definition