| Function | System Include File | Function Prototype | Description |
|---|---|---|---|
| abort | stdlib.h | void abort(void); | Stops a program abnormally. |
| abs | stdlib.h | int abs(int n); | Calculates the absolute value of an integer argument n. |
| acos | math.h | double acos(double x); | Calculates the arc cosine of x. |
| asctime | time.h | char *asctime(const struct tm *time); | Converts the time that is stored as a structure to a character string. |
| asctime_r | time.h | char *asctime_r (const struct tm *tm, char *buf); | Converts tm that is stored as a structure to a character string. (Restartable version of asctime.) |
| asin | math.h | double asin(double x); | Calculates the arc sine of x. |
| assert | assert.h | void assert(int expression); | Prints a diagnostic message and ends the program if the expression is false. |
| atan | math.h | double atan(double x); | Calculates the arc tangent of x. |
| atan2 | math.h | double atan2(double y, double x); | Calculates the arc tangent of y/x. |
| atexit | stdlib.h | int atexit(void (*func)(void)); | Registers a function to be called at normal termination. |
| atof | stdlib.h | double atof(const char *string); | Converts string to a double-precision floating-point value. |
| atoi | stdlib.h | int atoi(const char *string); | Converts string to an integer. |
| atol | stdlib.h | long int atol(const char *string); | Converts string to a long integer. |
| bsearch | stdlib.h | void *bsearch(const void *key, const void *base, size_t num, size_t size, int (*compare) (const void *element1, const void *element2)); | Performs a binary search on an array of num elements, each of size bytes. The array must be sorted in ascending order by the function pointed to by compare. |
| btowc | stdio.h wchar.h | wint_t btowc(int c); | Determines whether c constitues a valid multibyte character in the initial shift state. |
| calloc | stdlib.h | void *calloc(size_t num, size_t size); | Reserves storage space for an array of num elements, each of size size, and initializes the values of all elements to 0. |
| catclose6 | nl_types.h | int catclose (nl_catd catd); | Closes a previously opened message catalog. |
| catgets6 | nl_types.h | char *catgets(nl_catd catd, int set_id, int msg_id, const char *s); | Retrieves a message from an open message catalog. |
| catopen6 | nl_types.h | nl_catd catopen (const char *name, int oflag); | Opens a message catalog, which must be done before a message can be retrieved. |
| ceil | math.h | double ceil(double x); | Calculates the double value representing the smallest integer that is greater than or equal to x. |
| clearerr | stdio.h | void clearerr(FILE *stream); | Resets the error indicators and the end-of-file indicator for stream. |
| clock | time.h | clock_t clock(void); | Returns the processor time that has elapsed since the job was started. |
| cos | math.h | double cos(double x); | Calculates the cosine of x. |
| cosh | math.h | double cosh(double x); | Calculates the hyperbolic cosine of x. |
| ctime | time.h | char *ctime(const time_t *time); | Converts time to a character string. |
| ctime64 | time.h | char *ctime64(const time64_t *time); | Converts time to a character string. |
| ctime_r | time.h | char *ctime_r(const time_t *time, char *buf); | Converts time to a character string. (Restartable version of ctime.) |
| ctime64_r | time.h | char *ctime64_r(const time64_t *time, char *buf); | Converts time to a character string. (Restartable version of ctime64.) |
| difftime | time.h | double difftime(time_t time2, time_t time1); | Computes the difference between time2 and time1. |
| difftime64 | time.h | double difftime64(time64_t time2, time64_t time1); | Computes the difference between time2 and time1. |
| div | stdlib.h | div_t div(int numerator, int denominator); | Calculates the quotient and remainder of the division of numerator by denominator. |
| erf | math.h | double erf(double x); | Calculates the error function of x. |
| erfc | math.h | double erfc(double x); | Calculates the error function for large values of x. |
| exit | stdlib.h | void exit(int status); | Ends a program normally. |
| exp | math.h | double exp(double x); | Calculates the exponential function of a floating-point argument x. |
| fabs | math.h | double fabs(double x); | Calculates the absolute value of a floating-point argument x. |
| fclose | stdio.h | int fclose(FILE *stream); | Closes the specified stream. |
| fdopen5 | stdio.h | FILE *fdopen(int handle, const char *type); | Associates an input or output stream with the file identified by handle. |
| feof | stdio.h | int feof(FILE *stream); | Tests whether the end-of-file flag is set for a given stream. |
| ferror | stdio.h | int ferror(FILE *stream); | Tests for an error indicator in reading from or writing to stream. |
| fflush1 | stdio.h | int fflush(FILE *stream); | Writes the contents of the buffer associated with the output stream. |
| fgetc1 | stdio.h | int fgetc(FILE *stream); | Reads a single unsigned character from the input stream. |
| fgetpos1 | stdio.h | int fgetpos(FILE *stream, fpos_t *pos); | Stores the current position of the file pointer associated with stream into the object pointed to by pos. |
| fgets1 | stdio.h | char *fgets(char *string, int n, FILE *stream); | Reads a string from the input stream. |
| fgetwc6 | stdio.h wchar.h | wint_t fgetwc(FILE *stream); | Reads the next multibyte character from the input stream pointed to by stream. |
| fgetws6 | stdio.h wchar.h | wchar_t *fgetws(wchar_t *wcs, int n, FILE *stream); | Reads wide characters from the stream into the array pointed to by wcs. |
| fileno5 | stdio.h | int fileno(FILE *stream); | Determines the file handle currently associated with stream. |
| floor | math.h | double floor(double x); | Calculates the floating-point value representing the largest integer less than or equal to x. |
| fmod | math.h | double fmod(double x, double y); | Calculates the floating-point remainder of x/y. |
| fopen | stdio.h | FILE *fopen(const char *filename, const char *mode); | Opens the specified file. |
| fprintf | stdio.h | int fprintf(FILE *stream, const char *format-string, arg-list); | Formats and prints characters and values to the output stream. |
| fputc1 | stdio.h | int fputc(int c, FILE *stream); | Prints a character to the output stream. |
| fputs1 | stdio.h | int fputs(const char *string, FILE *stream); | Copies a string to the output stream. |
| fputwc6 | stdio.h wchar.h | wint_t fputwc(wchar_t wc, FILE *stream); | Converts the wide character wc to a multibyte character and writes it to the output stream pointed to by stream at the current position. |
| fputws6 | stdio.h wchar.h | int fputws(const wchar_t *wcs, FILE *stream); | Converts the wide-character string wcs to a multibyte-character string and writes it to stream as a multibyte character string. |
| fread | stdio.h | size_t fread(void *buffer, size_t size, size_t count, FILE *stream); | Reads up to count items of size length from the input stream, and stores them in buffer. |
| free | stdlib.h | void free(void *ptr); | Frees a block of storage. |
| freopen | stdio.h | FILE *freopen(const char *filename, const char *mode, FILE *stream); | Closes stream, and reassigns it to the file specified. |
| frexp | math.h | double frexp(double x, int *expptr); | Separates a floating-point number into its mantissa and exponent. |
| fscanf | stdio.h | int fscanf(FILE *stream, const char *format-string, arg-list); | Reads data from stream into locations given by arg-list. |
| fseek1 | stdio.h | int fseek(FILE *stream, long int offset, int origin); | Changes the current file position associated with stream to a new location. |
| fsetpos1 | stdio.h | int fsetpos(FILE *stream, const fpos_t *pos); | Moves the current file position to a new location determined by pos. |
| ftell1 | stdio.h | long int ftell(FILE *stream); | Gets the current position of the file pointer. |
| fwide6 | stdio.h wchar.h | int fwide(FILE *stream, int mode); | Determines the orientation of the stream pointed to by stream. |
| fwprintf6 | stdio.h wchar.h | int fwprintf(FILE *stream, const wchar_t *format, arg-list); | Writes output to the stream pointed to by stream. |
| fwrite | stdio.h | size_t fwrite(const void *buffer, size_t size,size_t count, FILE *stream); | Writes up to count items of size length from buffer to stream. |
| fwscanf6 | stdio.h wchar.h | int fwscanf(FILE *stream, const wchar_t *format, arg-list) | Reads input from the stream pointed to by stream. |
| gamma | math.h | double gamma(double x); | Computes the Gamma Function |
| getc1 | stdio.h | int getc(FILE *stream); | Reads a single character from the input stream. |
| getchar1 | stdio.h | int getchar(void); | Reads a single character from stdin. |
| getenv | stdlib.h | char *getenv(const char *varname); | Searches environment variables for varname. |
| gets | stdio.h | char *gets(char *buffer); | Reads a string from stdin, and stores it in buffer. |
| getwc6 | stdio.h wchar.h | wint_t getwc(FILE *stream); | Reads the next multibyte character from stream, converts it to a wide character and advances the associated file position indicator for stream. |
| getwchar6 | wchar.h | wint_t getwchar(void); | Reads the next multibyte character from stdin, converts it to a wide character, and advances the associated file position indicator for stdin. |
| gmtime | time.h | struct tm *gmtime(const time_t *time); | Converts a time value to a structure of type tm. |
| gmtime64 | time.h | struct tm *gmtime64(const time64_t *time); | Converts a time value to a structure of type tm. |
| gmtime_r | time.h | struct tm *gmtime_r (const time_t *time, struct tm *result); | Converts a time value to a structure of type tm. (Restartable version of gmtime.) |
| gmtime64_r | time.h | struct tm *gmtime64_r (const time64_t *time, struct tm *result); | Converts a time value to a structure of type tm. (Restartable version of gmtime64.) |
| hypot | math.h | double hypot(double side1, double side2); | Calculates the hypotenuse of a right-angled triangle with sides of length side1 and side2. |
| isalnum | ctype.h | int isalnum(int c); | Tests if c is alphanumeric. |
| isalpha | ctype.h | int isalpha(int c); | Tests if c is alphabetic. |
| isascii4 | ctype.h | int isascii(int c); | Tests if c is within the 7-bit US-ASCII range. |
| isblank | ctype.h | int isblank(int c); | Tests if c is a blank or tab character. |
| iscntrl | ctype.h | int iscntrl(int c); | Tests if c is a control character. |
| isdigit | ctype.h | int isdigit(int c); | Tests if c is a decimal digit. |
| isgraph | ctype.h | int isgraph(int c); | Tests if c is a printable character excluding the space. |
| islower | ctype.h | int islower(int c); | Tests if c is a lowercase letter. |
| isprint | ctype.h | int isprint(int c); | Tests if c is a printable character including the space. |
| ispunct | ctype.h | int ispunct(int c); | Tests if c is a punctuation character. |
| isspace | ctype.h | int isspace(int c); | Tests if c is a whitespace character. |
| isupper | ctype.h | int isupper(int c); | Tests if c is an uppercase letter. |
| iswalnum4 | wctype.h | int iswalnum (wint_t wc); | Checks for any alphanumeric wide character. |
| iswalpha4 | wctype.h | int iswalpha (wint_t wc); | Checks for any alphabetic wide character. |
| iswblank4 | wctype.h | int iswblank (wint_t wc); | Checks for any blank or tab wide character. |
| iswcntrl4 | wctype.h | int iswcntrl (wint_t wc); | Tests for any control wide character. |
| iswctype4 | wctype.h | int iswctype(wint_t wc, wctype_t wc_prop); | Determines whether or not the wide character wc has the property wc_prop. |
| iswdigit4 | wctype.h | int iswdigit (wint_t wc); | Checks for any decimal-digit wide character. |
| iswgraph4 | wctype.h | int iswgraph (wint_t wc); | Checks for any printing wide character except for the wide-character space. |
| iswlower4 | wctype.h | int iswlower (wint_t wc); | Checks for any lowercase wide character. |
| iswprint4 | wctype.h | int iswprint (wint_t wc); | Checks for any printing wide character. |
| iswpunct4 | wctype.h | int iswpunct (wint_t wc); | Test for a wide non-alphanumeric, non-space character. |
| iswspace4 | wctype.h | int iswspace (wint_t wc); | Checks for any wide character that corresponds to an implementation-defined set of wide characters for which iswalnum is false. |
| iswupper4 | wctype.h | int iswupper (wint_t wc); | Checks for any uppercase wide character. |
| iswxdigit4 | wctype.h | int iswxdigit (wint_t wc); | Checks for any hexadecimal digit character. |
| isxdigit4 | wctype.h | int isxdigit(int c); | Tests if c is a hexadecimal digit. |
| j0 | math.h | double j0(double x); | Calculates the Bessel function value of the first kind of order 0. |
| j1 | math.h | double j1(double x); | Calculates the Bessel function value of the first kind of order 1. |
| jn | math.h | double jn(int n, double x); | Calculates the Bessel function value of the first kind of order n. |
| labs | stdlib.h | long int labs(long int n); | Calculates the absolute value of n. |
| ldexp | math.h | double ldexp(double x, int exp); | Returns the value of x multiplied by (2 to the power of exp). |
| ldiv | stdlib.h | ldiv_t ldiv(long int numerator, long int denominator); | Calculates the quotient and remainder of numerator/denominator. |
| localeconv | locale.h | struct lconv *localeconv(void); | Formats numeric quantities in struct lconv according to the current locale. |
| localtime | time.h | struct tm *localtime(const time_t *timeval); | Converts timeval to a structure of type tm. |
| localtime64 | time.h | struct tm *localtime64(const time64_t *timeval); | Converts timeval to a structure of type tm. |
| localtime_r | time.h | struct tm *localtime_r (const time_t *timeval, struct tm *result); | Converts a time value to a structure of type tm. (Restartable version of localtime.) |
| localtime64_r | time.h | struct tm *localtime64_r (const time64_t *timeval, struct tm *result); | Converts a time value to a structure of type tm. (Restartable version of localtime64.) |
| log | math.h | double log(double x); | Calculates the natural logarithm of x. |
| log10 | math.h | double log10(double x); | Calculates the base 10 logarithm of x. |
| longjmp | setjmp.h | void longjmp(jmp_buf env, int value); | Restores a stack environment previously set in env by the setjmp function. |
| malloc | stdlib.h | void *malloc(size_t size); | Reserves a block of storage. |
| mblen | stdlib.h | int mblen(const char *string, size_t n); | Determines the length of a multibyte character string. |
| mbrlen4 | wchar.h | int mbrlen (const char *s, size_t n, mbstate_t *ps); | Determines the length of a multibyte character. (Restartable version of mblen.) |
| mbrtowc4 | wchar.h | int mbrtowc (wchar_t *pwc, const char *s, size_t n, mbstate_t *ps); | Convert a multibyte character to a wide character (Restartable version of mbtowc.) |
| mbsinit4 | wchar.h | int mbsinit (const mbstate_t *ps); | Test state object *ps for initial state. |
| mbsrtowcs4 | wchar.h | size_t mbsrtowc (wchar_t *dst, const char **src, size_t len, mbstate_t *ps); | Convert multibyte string to a wide character string. (Restartable version of mbstowcs.) |
| mbstowcs | stdlib.h | size_t mbstowcs(wchar_t *pwc, const char *string, size_t n); | Converts the multibyte characters in string to their corresponding wchar_t codes, and stores not more than n codes in pwc. |
| mbtowc | stdlib.h | int mbtowc(wchar_t *pwc, const char *string, size_t n); | Stores the wchar_t code corresponding to the first n bytes of multibyte character string into the wchar_t character pwc. |
| memchr | string.h | void *memchr(const void *buf, int c, size_t count); | Searches the first count bytes of buf for the first occurrence of c converted to an unsigned character. |
| memcmp | string.h | int memcmp(const void *buf1, const void *buf2, size_t count); | Compares up to count bytes of buf1 and buf2. |
| memcpy | string.h | void *memcpy(void *dest, const void *src, size_t count); | Copies count bytes of src to dest. |
| memmove | string.h | void *memmove(void *dest, const void *src, size_t count); | Copies count bytes of src to dest. Allows copying between objects that overlap. |
| memset | string.h | void *memset(void *dest, int c, size_t count); | Sets count bytes of dest to a value c. |
| mktime | time.h | time_t mktime(struct tm *time); | Converts local time into calendar time. |
| mktime64 | time.h | time64_t mktime64(struct tm *time); | Converts local time into calendar time. |
| modf | math.h | double modf(double x, double *intptr); | Breaks down the floating-point value x into fractional and integral parts. |
| nextafter | math.h | double nextafter(double x, double y); | Calculates the next representable value after x in the direction of y. |
| nextafterl | math.h | long double nextafterl(long double x, long double y); | Calculates the next representable value after x in the direction of y. |
| nexttoward | math.h | double nexttoward(double x, long double y); | Calculates the next representable value after x in the direction of y. |
| nexttowardl | math.h | long double nexttowardl(long double x, long double y); | Calculates the next representable value after x in the direction of y. |
| nl_langinfo4 | langinfo.h | char *nl_langinfo(nl_item item); | Retrieve from the current locale the string that describes the requested information specified by item. |
| perror | stdio.h | void perror(const char *string); | Prints an error message to stderr. |
| pow | math.h | double pow(double x, double y); | Calculates the value x to the power y. |
| printf | stdio.h | int printf(const char *format-string, arg-list); | Formats and prints characters and values to stdout. |
| putc1 | stdio.h | int putc(int c, FILE *stream); | Prints c to the output stream. |
| putchar1 | stdio.h | int putchar(int c); | Prints c to stdout. |
| putenv | stdlib.h | int *putenv(const char *varname); | Sets the value of an environment variable by altering an existing variable or creating a new one. |
| puts | stdio.h | int puts(const char *string); | Prints a string to stdout. |
| putwc6 | stdio.h wchar.h | wint_t putwchar(wchar_t wc, FILE *stream); | Converts the wide character wc to a multibyte character, and writes it to the stream at the current position. |
| putwchar6 | wchar.h | wint_t putwchar(wchar_t wc); | Converts the wide character wc to a multibyte character and writes it to stdout. |
| qsort | stdlib.h | void qsort(void *base, size_t num, size_t width, int(*compare)(const void *element1, const void *element2)); | Performs a quick sort of an array of num elements, each of width bytes in size. |
| quantexpd32 | math.h | _Decimal32 quantized32(_Decimal32 x, _Decimal32 y); | Compute the quantum exponent of a single-precision decimal floating-point value. |
| quantexpd64 | math.h | _Decimal64 quantized64(_Decimal64 x, _Decimal64 y); | Compute the quantum exponent of a double-precision decimal floating-point value. |
| quantexpd128 | math.h | _Decimal128 quantized128(_Decimal128 x, _Decimal128 y); | Compute the quantum exponent of a quad-precision decimal floating-point value. |
| quantized32 | math.h | int quantexpd32(_Decimal32 x); | Set the quantum exponent of a single-precision decimal floating-point value to the quantum exponent of another single-precision decimal floating-point value. |
| quantized64 | math.h | int quantexpd64(_Decimal64 x); | Set the quantum exponent of a double-precision decimal floating-point value to the quantum exponent of another double-precision decimal floating-point value. |
| quantized128 | math.h | int quantexpd128(_Decimal128 x); | Set the quantum exponent of a quad-precision decimal floating-point value to the quantum exponent of another quad-precision decimal floating-point value. |
| samequantumd32 | math.h | __bool__ samequantumd32(_Decimal32 x, _Decimal32 y); | Determine if the quantum exponents of two single-precision decimal floating-point values are the same. |
| samequantumd64 | math.h | __bool__ samequantumd64(_Decimal64 x, _Decimal64 y); | Determine if the quantum exponents of two double-precision decimal floating-point values are the same. |
| samequantumd128 | math.h | __bool__ samequantumd128(_Decimal128 x, _Decimal128 y); | Determine if the quantum exponents of two quad-precision decimal floating-point values are the same. |
| raise | signal.h | int raise(int sig); | Sends the signal sig to the running program. |
| rand | stdlib.h | int rand(void); | Returns a pseudo-random integer. |
| rand_r | stdlib.h | int rand_r(void); | Returns a pseudo-random integer. (Restartable version) |
| realloc | stdlib.h | void *realloc(void *ptr, size_t size); | Changes the size of a previously reserved storage block. |
| regcomp | regex.h | int regcomp(regex_t *preg, const char *pattern, int cflags); | Compiles the source regular expression pointed to by pattern into an executable version and stores it in the location pointed to by preg. |
| regerror | regex.h | size_t regerror(int errcode, const regex_t *preg, char *errbuf, size_t errbuf_size); | Finds the description for the error code errcode for the regular expression preg. |
| regexec | regex.h | int regexec(const regex_t *preg, const char *string, size_t nmatch, regmatch_t *pmatch, int eflags); | Compares the null-ended string string against the compiled regular expression preg to find a match between the two. |
| regfree | regex.h | void regfree(regex_t *preg); | Frees any memory that was allocated by regcomp to implement the regular expression preg. |
| remove | stdio.h | int remove(const char *filename); | Deletes the file specified by filename. |
| rename | stdio.h | int rename(const char *oldname, const char *newname); | Renames the specified file. |
| rewind1 | stdio.h | void rewind(FILE *stream); | Repositions the file pointer associated with stream to the beginning of the file. |
| scanf | stdio.h | int scanf(const char *format-string, arg-list); | Reads data from stdin into locations given by arg-list. |
| setbuf | stdio.h | void setbuf(FILE *stream, char *buffer); | Controls buffering for stream. |
| setjmp | setjmp.h | int setjmp(jmp_buf env); | Saves a stack environment that can be subsequently restored by longjmp. |
| setlocale | locale.h | char *setlocale(int category, const char *locale); | Changes or queries variables defined in the locale. |
| setvbuf | stdio.h | int setvbuf(FILE *stream, char *buf, int type, size_t size); | Controls buffering and buffer size for stream. |
| signal | signal.h | void(*signal (int sig, void(*func)(int))) (int); | Registers func as a signal handler for the signal sig. |
| sin | math.h | double sin(double x); | Calculates the sine of x. |
| sinh | math.h | double sinh(double x); | Calculates the hyperbolic sine of x. |
| snprintf | stdio.h | int snprintf(char *outbuf, size_t n, const char*, …) | Same as sprintf except that the function will stop after n characters have been written to outbuf. |
| sprintf | stdio.h | int sprintf(char *buffer, const char *format-string, arg-list); | Formats and stores characters and values in buffer. |
| sqrt | math.h | double sqrt(double x); | Calculates the square root of x. |
| srand | stdlib.h | void srand(unsigned int seed); | Sets the seed for the pseudo-random number generator. |
| sscanf | stdio.h | int sscanf(const char *buffer, const char *format, arg-list); | Reads data from buffer into the locations given by arg-list. |
| strcasecmp | strings.h | int srtcasecmp(const char *string1, const char *string2); | Compares strings without case sensitivity. |
| strcat | string.h | char *strcat(char *string1, const char *string2); | Concatenates string2 to string1. |
| strchr | string.h | char *strchr(const char *string, int c); | Locates the first occurrence of c in string. |
| strcmp | string.h | int strcmp(const char *string1, const char *string2); | Compares the value of string1 to string2. |
| strcoll | string.h | int strcoll(const char *string1, const char *string2); | Compares two strings using the collating sequence in the current locale. |
| strcpy | string.h | char *strcpy(char *string1, const char *string2); | Copies string2 into string1. |
| strcspn | string.h | size_t strcspn(const char *string1, const char *string2); | Returns the length of the initial substring of string1 consisting of characters not contained in string2. |
| strerror | string.h | char *strerror(int errnum); | Maps the error number in errnum to an error message string. |
| strfmon4 | wchar.h | int strfmon (char *s, size_t maxsize, const char *format, …); | Converts monetary value to string. |
| strftime | time.h | size_t strftime (char *dest, size_t maxsize, const char *format, const struct tm *timeptr); | Stores characters in an array pointed to by dest, according to the string determined by format. |
| strlen | string.h | size_t strlen(const char *string); | Calculates the length of string. |
| strncasecmp | strings.h | int strncasecmp(const char *string1, const char *string2, size_t count); | Compares strings without case sensitivity. |
| strncat | string.h | char *strncat(char *string1, const char *string2, size_t count); | Concatenates up to count characters of string2 to string1. |
| strncmp | string.h | int strncmp(const char *string1, const char *string2, size_t count); | Compares up to count characters of string1 and string2. |
| strncpy | string.h | char *strncpy(char *string1, const char *string2, size_t count); | Copies up to count characters of string2 to string1. |
| strpbrk | string.h | char *strpbrk(const char *string1, const char *string2); | Locates the first occurrence in string1 of any character in string2. |
| strptime4 | time.h | char *strptime (const char *buf, const char *format, struct tm *tm); | Date and time conversion |
| strrchr | string.h | char *strrchr(const char *string, int c); | Locates the last occurrence of c in string. |
| strspn | string.h | size_t strspn(const char *string1, const char *string2); | Returns the length of the initial substring of string1 consisting of characters contained in string2. |
| strstr | string.h | char *strstr(const char *string1, const char *string2); | Returns a pointer to the first occurrence of string2 in string1. |
| strtod | stdlib.h | double strtod(const char *nptr, char **endptr); | Converts nptr to a double precision value. |
| strtod32 | stdlib.h | _Decimal32 strtod32(const char *nptr, char **endptr); | Converts nptr to a single-precision decimal floating-point value. |
| strtod64 | stdlib.h | _Decimal64 strtod64(const char *nptr, char **endptr); | Converts nptr to a double-precision decimal floating-point value. |
| strtod128 | stdlib.h | _Decimal128 strtod128(const char *nptr, char **endptr); | Converts nptr to a quad-precision decimal floating-point value. |
| strtof | stdlib.h | float strtof(const char *nptr, char **endptr); | Converts nptr to a float value. |
| strtok | string.h | char *strtok(char *string1, const char *string2); | Locates the next token in string1 delimited by the next character in string2. |
| strtok_r | string.h | char *strtok_r(char *string, const char *seps, char **lasts); | Locates the next token in string delimited by the next character in seps. (Restartable version of strtok.) |
| strtol | stdlib.h | long int strtol(const char *nptr, char **endptr, int base); | Converts nptr to a signed long integer. |
| strtold | stdlib.h | long double strtold(const char *nptr, char **endptr); | Converts nptr to a long double value. |
| strtoul | stdlib.h | unsigned long int strtoul(const char *string1, char **string2, int base); | Converts string1 to an unsigned long integer. |
| strxfrm | string.h | size_t strxfrm(char *string1, const char *string2, size_t count); | Converts string2 and places the result in string1. The conversion is determined by the program’s current locale. |
| swprintf | wchar.h | int swprintf(wchar_t *wcsbuffer, size_t n, const wchar_t *format, arg-list); | Formats and stores a series of wide characters and values into the wide-character buffer wcsbuffer. |
| swscanf | wchar.h | int swscanf (const wchar_t *buffer, const wchar_t *format, arg-list) | Reads data from buffer into the locations given by arg-list. |
| system | stdlib.h | int system(const char *string); | Passes string to the system command analyzer. |
| tan | math.h | double tan(double x); | Calculates the tangent of x. |
| tanh | math.h | double tanh(double x); | Calculates the hyperbolic tangent of x. |
| time | time.h | time_t time(time_t *timeptr); | Returns the current calendar time. |
| time64 | time.h | time64_t time64(time64_t *timeptr); | Returns the current calendar time. |
| tmpfile | stdio.h | FILE *tmpfile(void); | Creates a temporary binary file and opens it. |
| tmpnam | stdio.h | char *tmpnam(char *string); | Generates a temporary file name. |
| toascii | ctype.h | int toascii(int c); | Converts c to a character in the 7-bit US-ASCII character set. |
| tolower | ctype.h | int tolower(int c); | Converts c to lowercase. |
| toupper | ctype.h | int toupper(int c); | Converts c to uppercase. |
| towctrans | wctype.h | wint_t towctrans(wint_t wc, wctrans_t desc); | Translates the wide character wc based on the mapping described by desc. |
| towlower4 | wctype.h | wint_t towlower (wint_t wc); | Converts uppercase letter to lowercase letter. |
| towupper4 | wctype.h | wint_t towupper (wint_t wc); | Converts lowercase letter to uppercase letter. |
| ungetc1 | stdio.h | int ungetc(int c, FILE *stream); | Pushes c back onto the input stream. |
| ungetwc6 | stdio.h wchar.h | wint_t ungetwc(wint_t wc, FILE *stream); | Pushes the wide character wc back onto the input stream. |
| va_arg | stdarg.h | var_type va_arg(va_list arg_ptr, var_type); | Returns the value of one argument and modifies arg_ptr to point to the next argument. |
| va_copy | stdarg.h | void va_copy(va_list dest, va_list src); | Initializes dest as a copy of src. |
| va_end | stdarg.h | void va_end(va_list arg_ptr); | Facilitates normal return from variable argument list processing. |
| va_start | stdarg.h | void va_start(va_list arg_ptr, variable_name); | Initializes arg_ptr for subsequent use by va_arg and va_end. |
| vfprintf | stdio.h stdarg.h | int vfprintf(FILE *stream, const char *format, va_list arg_ptr); | Formats and prints characters to the output stream using a variable number of arguments. |
| vfscanf | stdio.h stdarg.h | int vfscanf(FILE *stream, const char *format, va_list arg_ptr); | Reads data from a specified stream into locations given by a variable number of arguments. |
| vfwprintf6 | stdarg.h stdio.h wchar.h | int vfwprintf(FILE *stream, const wchar_t *format, va_list arg); | Equivalent to fwprintf, except that the variable argument list is replaced by arg. |
| vfwscanf | stdio.h stdarg.h | int vfwscanf(FILE *stream, const wchar_t *format, va_list arg_ptr); | Reads wide data from a specified stream into locations given by a variable number of arguments. |
| vprintf | stdio.h stdarg.h | int vprintf(const char *format, va_list arg_ptr); | Formats and prints characters to stdout using a variable number of arguments. |
| vscanf | stdio.h stdarg.h | int vscanf(const char *format, va_list arg_ptr); | Reads data from stdin into locations given by a variable number of arguments. |
| vsprintf | stdio.h stdarg.h | int vsprintf(char *target-string, const char *format, va_list arg_ptr); | Formats and stores characters in a buffer using a variable number of arguments. |
| vsnprintf | stdio.h | int vsnprintf(char *outbuf, size_t n, const char*, va_list); | Same as vsprintf except that the function will stop after n characters have been written to outbuf. |
| vsscanf | stdio.h stdarg.h | int vsscanf(const char*buffer, const char *format, va_list arg_ptr); | Reads data from a buffer into locations given by a variable number of arguments. |
| vswprintf | stdarg.h wchar.h | int vswprintf(wchar_t *wcsbuffer, size_t n, const wchar_t *format, va_list arg); | Formats and stores a series of wide characters and values in the buffer wcsbuffer. |
| vswscanf | stdio.h wchar.h | int vswscanf(const wchar_t *buffer, const wchar_t *format, va_list arg_ptr); | Reads wide data from a buffer into locations given by a variable number of arguments. |
| vwprintf6 | stdarg.h wchar.h | int vwprintf(const wchar_t *format, va_list arg); | Equivalent to wprintf, except that the variable argument list is replaced by arg. |
| vwscanf | stdio.h wchar.h | int vwscanf(const wchar_t *format, va_list arg_ptr); | Reads wide data from stdin into locations given by a variable number of arguments. |
| wcrtomb4 | wchar.h | int wcrtomb (char *s, wchar_t wchar, mbstate_t *pss); | Converts a wide character to a multibyte character. (Restartable version of wctomb.) |
| wcscat | wchar.h | wchar_t *wcscat(wchar_t *string1, const wchar_t *string2); | Appends a copy of the string pointed to by string2 to the end of the string pointed to by string1. |
| wcschr | wchar.h | wchar_t *wcschr(const wchar_t *string, wchar_t character); | Searches the wide-character string pointed to by string for the occurrence of character. |
| wcscmp | wchar.h | int wcscmp(const wchar_t *string1, const wchar_t *string2); | Compares two wide-character strings, *string1 and *string2. |
| wcscoll4 | wchar.h | int wcscoll (const wchar_t *wcs1, const wchar_t *wcs2); | Compares two wide-character strings using the collating sequence in the current locale. |
| wcscpy | wchar.h | wchar_t *wcscpy(wchar_t *string1, const wchar_t *string2); | Copies the contents of *string2 (including the ending wchar_t null character) into *string1. |
| wcscspn | wchar.h | size_t wcscspn(const wchar_t *string1, const wchar_t *string2); | Determines the number of wchar_t characters in the initial segment of the string pointed to by *string1 that do not appear in the string pointed to by *string2. |
| wcsftime | wchar.h | size_t wcsftime(wchar_t *wdest, size_t maxsize, const wchar_t *format, const struct tm *timeptr); | Converts the time and date specification in the timeptr structure into a wide-character string. |
| wcslen | wchar.h | size_t wcslen(const wchar_t *string); | Computes the number of wide-characters in the string pointed to by string. |
| wcslocaleconv | locale.h | struct wcslconv *wcslocaleconv(void); | Formats numeric quantities in struct wcslconv according to the current locale. |
| wcsncat | wchar.h | wchar_t *wcsncat(wchar_t *string1, const wchar_t *string2, size_t count); | Appends up to count wide characters from string2 to the end of string1, and appends a wchar_t null character to the result. |
| wcsncmp | wchar.h | int wcsncmp(const wchar_t *string1, const wchar_t *string2, size_t count); | Compares up to count wide characters in string1 to string2. |
| wcsncpy | wchar.h | wchar_t *wcsncpy(wchar_t *string1, const wchar_t *string2, size_t count); | Copies up to count wide characters from string2 to string1. |
| wcspbrk | wchar.h | wchar_t *wcspbrk(const wchar_t *string1, const wchar_t *string2); | Locates the first occurrence in the string pointed to by string1 of any wide characters from the string pointed to by string2. |
| wcsptime | wchar.h | wchar_t *wcsptime ( const wchar_t *buf, const wchar_t *format, struct tm *tm ); | Date and time conversion. Equivalent to strptime(), except that it uses wide characters. |
| wcsrchr | wchar.h | wchar_t *wcsrchr(const wchar_t *string, wchar_t character); | Locates the last occurrence of character in the string pointed to by string. |
| wcsrtombs4 | wchar.h | size_t wcsrtombs (char *dst, const wchar_t **src, size_t len, mbstate_t *ps); | Converts wide character string to multibyte string. (Restartable version of wcstombs.) |
| wcsspn | wchar.h | size_t wcsspn(const wchar_t *string1, const wchar_t *string2); | Computes the number of wide characters in the initial segment of the string pointed to by string1, which consists entirely of wide characters from the string pointed to by string2. |
| wcsstr | wchar.h | wchar_t *wcsstr(const wchar_t *wcs1, const wchar_t *wcs2); | Locates the first occurrence of wcs2 in wcs1. |
| wcstod | wchar.h | double wcstod(const wchar_t *nptr, wchar_t **endptr); | Converts the initial portion of the wide-character string pointed to by nptr to a double value. |
| wcstod32 | wchar.h | _Decimal32 wcstod32(const wchar_t *nptr, wchar_t **endptr); | Converts the initial portion of the wide-character string pointed to by nptr to a single-precision decimal floating-point value. |
| wcstod64 | wchar.h | _Decimal64 wcstod64(const wchar_t *nptr, wchar_t **endptr); | Converts the initial portion of the wide-character string pointed to by nptr to a double-precision decimal floating-point value. |
| wcstod128 | wchar.h | _Decimal128 wcstod128(const wchar_t *nptr, wchar_t **endptr); | Converts the initial portion of the wide-character string pointed to by nptr to a quad-precision decimal floating-point value. |
| wcstof | wchar.h | float wcstof(const wchar_t *nptr, wchar_t **endptr); | Converts the initial portion of the wide-character string pointed to by nptr to a float value. |
| wcstok | wchar.h | wchar_t *wcstok(wchar_t *wcs1, const wchar_t *wcs2, wchar_t **ptr) | Breaks wcs1 into a sequence of tokens, each of which is delimited by a wide character from the wide string pointed to by wcs2. |
| wcstol | wchar.h | long int wcstol(const wchar_t *nptr, wchar_t **endptr, int base); | Converts the initial portion of the wide-character string pointed to by nptr to a long integer value. |
| wcstold | wchar.h | long double wcstold(const wchar_t *nptr, wchar_t **endptr); | Converts the initial portion of the wide-character string pointed to by nptr to a long double value. |
| wcstombs | stdlib.h | size_t wcstombs(char *dest, const wchar_t *string, size_t count); | Converts the wchar_t string into a multibyte string dest. |
| wcstoul | wchar.h | unsigned long int wcstoul(const wchar_t *nptr, wchar_t **endptr, int base); | Converts the initial portion of the wide-character string pointed to by nptr to an unsigned long integer value. |
| wcsxfrm4 | wchar.h | size_t wcsxfrm (wchar_t *wcs1, const wchar_t *wcs2, size_t n); | Transforms a wide-character string to values which represent character collating weights and places the resulting wide-character string into an array. |
| wctob | stdarg.h wchar.h | int wctob(wint_t wc); | Determines whether wc corresponds to a member of the extended character set whose multibyte character representation is a single byte when in the initial shift state. |
| wctomb | stdlib.h | int wctomb(char *string, wchar_t character); | Converts the wchar_t value of character into a multibyte string. |
| wctrans | wctype.h | wctrans_t wctrans(const char *property); | Constructs a value with type wctrans_t that describes a mapping between wide characters identified by the string argument property. |
| wctype4 | wchar.h | wctype_t wctype (const char *property); | Obtains handle for character property classification. |
| wcwidth | wchar.h | int wcswidth(const wchar_t *pwcs, size_t n); | Determine the display width of a wide character string. |
| wmemchr | wchar.h | wchar_t *wmemchr(const wchar_t *s, wchar_t c, size_t n); | Locates the first occurrence of c in the initial n wide characters of the object pointed to by s. |
| wmemcmp | wchar.h | int wmemcmp(const wchar_t *s1, const wchar_t *s2, size_t n); | Compares the first n wide characters of the object pointed to by s1 to the first n characters of the object pointed to by s2. |
| wmemcpy | wchar.h | wchar_t *wmemcpy(wchar_t *s1, const wchar_t *s2, size_t n); | Copies n wide characters from the object pointed to by s2 to the object pointed to by s1. |
| wmemmove | wchar.h | wchar_t *wmemmove(wchar_t *s1, const wchar_t *s2, size_t n); | Copies n wide characters from the object pointed to by s2 to the object pointed to by s1. |
| wmemset | wchar.h | wchar_t *wmemset(wchar_t *s, wchar_t c, size_t n); | Copies the value of c into each of the first n wide characters of the object pointed to by s. |
| wprintf6 | wchar.h | int wprintf(const wchar_t *format, arg-list); | Equivalent to fwprintf with the argument stdout interposed before the arguments to wprintf. |
| wscanf6 | wchar.h | int wscanf(const wchar_t *format, arg-list); | Equivalent to fwscanf with the argument stdin interposed before the arguments of wscanf. |
| y0 | math.h | double y0(double x); | Calculates the Bessel function value of the second kind of order 0. |
| y1 | math.h | double y1(double x); | Calculates the Bessel function value of the second kind of order 1. |
| yn | math.h | double yn(int n, double x); | Calculates the Bessel function value of the second kind of order n. |
Categories: C language
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