stdlib.h - standard library definitions
#include <stdlib.h>
[] [Option Start] Some of the functionality described on this reference page extends the ISO C standard. Applications shall define the appropriate feature test macro (see XSH The Compilation Environment ) to enable the visibility of these symbols in this header. [Option End]The <stdlib.h> header shall define the following macros which shall expand to integer constant expressions:
- EXIT_FAILURE
- Unsuccessful termination for exit(); evaluates to a non-zero value.
- EXIT_SUCCESS
- Successful termination for exit(); evaluates to 0.
- {RAND_MAX}
- Maximum value returned by rand(); at least 32767.
The <stdlib.h> header shall define the following macro which shall expand to a positive integer expression with type size_t:
- {MB_CUR_MAX}
- Maximum number of bytes in a character specified by the current locale (category LC_CTYPE).
[] [Option Start] In the POSIX locale the value of {MB_CUR_MAX} shall be 1. [Option End]
The <stdlib.h> header shall define NULL as described in <stddef.h>.
The <stdlib.h> header shall define the following data types through typedef:
- div_t
- Structure type returned by the div() function.
- ldiv_t
- Structure type returned by the ldiv() function.
- lldiv_t
- Structure type returned by the lldiv() function.
- size_t
- As described in <stddef.h>.
- wchar_t
- As described in <stddef.h>.
[] [Option Start] In addition, the <stdlib.h> header shall define the following symbolic constants and macros as described in <sys/wait.h>:
WEXITSTATUS
WIFEXITED
WIFSIGNALED
WIFSTOPPED
WNOHANG
WSTOPSIG
WTERMSIG
WUNTRACED
[Option End]
The following shall be declared as functions and may also be defined as macros. Function prototypes shall be provided.
void _Exit(int); [][Option Start] long a64l(const char *); [Option End] void abort(void); int abs(int); int atexit(void (*)(void)); double atof(const char *); int atoi(const char *); long atol(const char *); long long atoll(const char *); void *bsearch(const void *, const void *, size_t, size_t, int (*)(const void *, const void *)); void *calloc(size_t, size_t); div_t div(int, int); [][Option Start] double drand48(void); double erand48(unsigned short [3]); [Option End] void exit(int); void free(void *); char *getenv(const char *); [][Option Start] int getsubopt(char **, char *const *, char **); [Option End] [][Option Start] int grantpt(int); char *initstate(unsigned, char *, size_t); long jrand48(unsigned short [3]); char *l64a(long); [Option End] long labs(long); [][Option Start] void lcong48(unsigned short [7]); [Option End] ldiv_t ldiv(long, long); long long llabs(long long); lldiv_t lldiv(long long, long long); [][Option Start] long lrand48(void); [Option End] void *malloc(size_t); int mblen(const char *, size_t); size_t mbstowcs(wchar_t *restrict, const char *restrict, size_t); int mbtowc(wchar_t *restrict, const char *restrict, size_t); [][Option Start] char *mkdtemp(char *); int mkstemp(char *); [Option End] [][Option Start] long mrand48(void); long nrand48(unsigned short [3]); [Option End] [][Option Start] int posix_memalign(void **, size_t, size_t); [Option End] [][Option Start] int posix_openpt(int); char *ptsname(int); int putenv(char *); [Option End] void qsort(void *, size_t, size_t, int (*)(const void *, const void *)); int rand(void); [][Option Start] int rand_r(unsigned *); [Option End] [][Option Start] long random(void); [Option End] void *realloc(void *, size_t); [][Option Start] char *realpath(const char *restrict, char *restrict); unsigned short *seed48(unsigned short [3]); [Option End] [][Option Start] int setenv(const char *, const char *, int); [Option End] [][Option Start] void setkey(const char *); char *setstate(char *); [Option End] void srand(unsigned); [][Option Start] void srand48(long); void srandom(unsigned); [Option End] double strtod(const char *restrict, char **restrict); float strtof(const char *restrict, char **restrict); long strtol(const char *restrict, char **restrict, int); long double strtold(const char *restrict, char **restrict); long long strtoll(const char *restrict, char **restrict, int); unsigned long strtoul(const char *restrict, char **restrict, int); unsigned long long strtoull(const char *restrict, char **restrict, int); int system(const char *); [][Option Start] int unlockpt(int); [Option End] [][Option Start] int unsetenv(const char *); [Option End] size_t wcstombs(char *restrict, const wchar_t *restrict, size_t); int wctomb(char *, wchar_t);[] [Option Start] Inclusion of the <stdlib.h> header may also make visible all symbols from <stddef.h>, <limits.h>, <math.h>, and <sys/wait.h>. [Option End]
None.
None.
None.
<limits.h>, <math.h>, <stddef.h>, <sys/types.h>, <sys/wait.h>
XSH The Compilation Environment, _Exit, a64l, abort, abs, atexit, atof, atoi, atol, bsearch, calloc, div, drand48, exit, free, getenv, getsubopt, grantpt, initstate, labs, ldiv, malloc, mblen, mbstowcs, mbtowc, mkdtemp, posix_memalign, posix_openpt, ptsname, putenv, qsort, rand, realloc, realpath, setenv, setkey, strtod, strtol, strtoul, system, unlockpt, unsetenv, wcstombs, wctomb
First released in Issue 3.
The DESCRIPTION is updated for alignment with the POSIX Threads Extension.
The ttyslot() and valloc() functions are marked LEGACY.
The type of the third argument to initstate() is changed from int to size_t. The type of the return value from setstate() is changed from char to char *, and the type of the first argument is changed from char * to const char *.
The Open Group Corrigendum U021/1 is applied, correcting the prototype for realpath() to be consistent with the reference page.
The Open Group Corrigendum U028/13 is applied, correcting the prototype for putenv() to be consistent with the reference page.
The rand_r() function is marked as part of the Thread-Safe Functions option.
Function prototypes for setenv() and unsetenv() are added.
The posix_memalign() function is added for alignment with IEEE Std 1003.1d-1999.
This reference page is updated to align with the ISO/IEC 9899:1999 standard.
The ecvt(), fcvt(), gcvt(), and mktemp() functions are marked LEGACY.
The ttyslot() and valloc() functions are removed as they were previously marked LEGACY.
Extensions beyond the ISO C standard are marked.
SD5-XBD-ERN-79 and SD5-XBD-ERN-105 are applied.
The LEGACY functions are removed.
The mkdtemp() function is added from The Open Group Technical Standard, 2006, Extended API Set Part 1.
The rand_r() function is marked obsolescent.
This reference page is clarified with respect to macros and symbolic constants.
The type of the first argument to setstate() is changed from const char * to char *.
POSIX.1-2008, Technical Corrigendum 1, XBD/TC1-2008/0066 [197] is applied.
POSIX.1-2008, Technical Corrigendum 2, XBD/TC2-2008/0075 [663] is applied.