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Standard library header <cstdlib>

From cppreference.com
< cpp‎ | header

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

This header provides miscellaneous utilities. Symbols defined here are used by several library components.

Contents

[edit] Macro constants

indicates program execution execution status
(macro constant) [edit]
MB_CUR_MAX
maximum number of bytes in a multibyte character with the current locale
(macro constant)
implementation-defined null pointer constant
(macro constant) [edit]
maximum possible value generated by std::rand
(macro constant) [edit]

[edit] Types

structure type, return of the std::div function
(typedef) [edit]
structure type, return of the std::ldiv function
(typedef) [edit]
(C++11)
structure type, return of the std::lldiv function
(typedef) [edit]
unsigned integer type returned by the sizeof operator
(typedef) [edit]

[edit] Functions

Process control
causes abnormal program termination (without cleaning up)
(function) [edit]
causes normal program termination with cleaning up
(function) [edit]
causes quick program termination without completely cleaning up
(function) [edit]
(C++11)
causes normal program termination without cleaning up
(function) [edit]
registers a function to be called on std::exit() invocation
(function) [edit]
registers a function to be called on quick_exit invocation
(function) [edit]
calls the host environment's command processor
(function) [edit]
access to the list of environment variables
(function) [edit]
Memory management
allocates memory
(function)
allocates aligned memory
(function)
allocates and zeroes memory
(function)
expands previously allocated memory block
(function)
deallocates previously allocated memory
(function)
Numeric string conversion
converts a byte string to a floating point value
(function) [edit]
converts a byte string to an integer value
(function) [edit]
converts a byte string to an integer value
(function) [edit]
converts a byte string to an unsigned integer value
(function) [edit]
converts a byte string to a floating point value
(function) [edit]
Wide string manipulation
returns the number of bytes in the next multibyte character
(function) [edit]
converts the next multibyte character to wide character
(function) [edit]
converts a wide character to its multibyte representation
(function) [edit]
converts a narrow multibyte character string to wide string
(function) [edit]
converts a wide string to narrow multibyte character string
(function) [edit]
Miscellaneous algorithms and math
generates a pseudo-random number
(function) [edit]
seeds pseudo-random number generator
(function) [edit]
sorts a range of elements with unspecified type
(function) [edit]
searches an array for an element of unspecified type
(function) [edit]
computes absolute value of an integral value (|x|)
(function) [edit]
computes quotient and remainder of integer division
(function) [edit]

[edit] Synopsis

namespace std {
  using size_t = /*implementation-defined*/;
  using div_t = /*implementation-defined*/ ;
  using ldiv_t = /*implementation-defined*/ ;
  using lldiv_t = /*implementation-defined*/ ;
}
 
#define NULL /*implementation-defined*/
#define EXIT_FAILURE /*implementation-defined*/
#define EXIT_SUCCESS /*implementation-defined*/
#define RAND_MAX /*implementation-defined*/
#define MB_CUR_MAX /*implementation-defined*/
 
namespace std {
  // start and termination
  [[noreturn]] void abort() noexcept;
  extern "C++" using /*atexit-handler*/ = void(); // exposition-only
  extern "C" using /*c-atexit-handler*/ = void(); // exposition-only
  int atexit( /*c-atexit-handler*/* func ) noexcept;
  int atexit( /*atexit-handler*/* func ) noexcept;
  int at_quick_exit( /*atexit-handler*/* func ) noexcept;
  int at_quick_exit( /*c-atexit-handler*/* func ) noexcept;
  [[noreturn]] void exit(int status);
  [[noreturn]] void _Exit(int status) noexcept;
  [[noreturn]] void quick_exit(int status) noexcept;
  char* getenv(const char* name);
  int system(const char* string);
 
  // C library memory allocation
  void* aligned_alloc(size_t alignment, size_t size);
  void* calloc(size_t nmemb, size_t size);
  void free(void* ptr);
  void* malloc(size_t size);
  void* realloc(void* ptr, size_t size);
  double atof(const char* nptr);
  int atoi(const char* nptr);
  long int atol(const char* nptr);
  long long int atoll(const char* nptr);
  double strtod(const char* nptr, char** endptr);
  float strtof(const char* nptr, char** endptr);
  long double strtold(const char* nptr, char** endptr);
  long int strtol(const char* nptr, char** endptr, int base);
  long long int strtoll(const char* nptr, char** endptr, int base);
  unsigned long int strtoul(const char* nptr, char** endptr, int base);
  unsigned long long int strtoull(const char* nptr, char** endptr, int base);
 
  // multibyte / wide string and character conversion functions
  int mblen(const char* s, size_t n);
  int mbtowc(wchar_t* pwc, const char* s, size_t n);
  int wctomb(char* s, wchar_t wchar);
  size_t mbstowcs(wchar_t* pwcs, const char* s, size_t n);
  size_t wcstombs(char* s, const wchar_t* pwcs, size_t n);
 
  // C standard library algorithms
  extern "C++" using /*compare-pred*/ = int(const void*, const void*); // exposition-only
  extern "C" using /*c-compare-pred*/ = int(const void *, const void *); // exposition-only
  void* bsearch( const void* key, const void* ptr, std::size_t count,
                 std::size_t size, /*compare-pred*/* comp );
  void* bsearch( const void* key, const void* ptr, std::size_t count,
                 std::size_t size, /*c-compare-pred*/* comp );
 
  extern "C++" using /*compare-pred*/ = int(const void*, const void*); // exposition-only
  extern "C" using /*c-compare-pred*/ = int(const void *, const void *); // exposition-only
  void qsort( void *ptr, std::size_t count, std::size_t size, /*compare-pred*/* comp );
  void qsort( void *ptr, std::size_t count, std::size_t size, /*c-compare-pred*/* comp );
 
  // low-quality random number generation
  int rand();
  void srand(unsigned int seed);
 
  // absolute values
  int abs(int j);
  long int abs(long int j);
  long long int abs(long long int j);
  float abs(float j);
  double abs(double j);
  long double abs(long double j);
  long int labs(long int j);
  long long int llabs(long long int j);
  div_t div(int numer, int denom);
  ldiv_t div(long int numer, long int denom);
  lldiv_t div(long long int numer, long long int denom);
  ldiv_t ldiv(long int numer, long int denom);
  lldiv_t lldiv(long long int numer, long long int denom);
}

[edit] See Also