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strtoll, _strtoll_l, wcstoll, _wcstoll_l

Converts a string to a long long value.

Syntax

long long strtoll(
   const char *strSource,
   char **endptr,
   int base
);
long long wcstoll(
   const wchar_t *strSource,
   wchar_t **endptr,
   int base
);
long long _strtoll_l(
   const char *strSource,
   char **endptr,
   int base,
   _locale_t locale
);
long long _wcstoll_l(
   const wchar_t *strSource,
   wchar_t **endptr,
   int base,
   _locale_t locale
);

Parameters

strSource
Null-terminated string to convert.

endptr
Pointer to the character that stops the scan.

base
Number base to use.

locale
The locale to use.

Return value

strtoll returns the value that's represented in the string strSource, except when the representation would cause an overflow—in that case, it returns LLONG_MAX or LLONG_MIN. The function returns 0 if no conversion can be performed. wcstoll returns values analogously to strtoll.

LLONG_MAX and LLONG_MIN are defined in LIMITS.H.

If strSource is NULL or the base is nonzero and either less than 2 or greater than 36, errno is set to EINVAL.

For more information about return codes, see errno, _doserrno, _sys_errlist, and _sys_nerr.

Remarks

The strtoll function converts strSource to a long long. Both functions stop reading the string strSource at the first character they can't recognize as part of a number. It may be the terminating null character, or it may be the first numeric character that's greater than or equal to base. wcstoll is a wide-character version of strtoll; its strSource argument is a wide-character string. Otherwise, these functions behave identically.

By default, this function's global state is scoped to the application. To change this behavior, see Global state in the CRT.

Generic-text routine mappings

TCHAR.H routine _UNICODE and _MBCS not defined _MBCS defined _UNICODE defined
_tcstoll strtoll strtoll wcstoll
_tcstoll_l _strtoll_l _strtoll_l _wcstoll_l

The locale's LC_NUMERIC category setting determines recognition of the radix character in strSource; for more information, see setlocale, _wsetlocale. The functions that don't have the _l suffix use the current locale; _strtoll_l and _wcstoll_l are identical to the corresponding functions that don't have the suffix, except that they instead use the locale that's passed in. For more information, see Locale.

If endptr isn't NULL, a pointer to the character that stopped the scan is stored at the location that's pointed to by endptr. If no conversion can be performed (no valid digits were found or an invalid base was specified), the value of strSource is stored at the location that's pointed to by endptr.

strtoll expects strSource to point to a string of the following form:

[whitespace] [{+ | -}] [0 [{ x | X }]] [digits | letters]

A whitespace may consist of space and tab characters, which are ignored; digits are one or more decimal digits; letters are one or more of the letters 'a' through 'z' (or 'A' through 'Z'). The first character that doesn't fit this form stops the scan. If base is between 2 and 36, then it's used as the base of the number. If base is 0, the initial characters of the string that's pointed to by strSource are used to determine the base. If the first character is '0' and the second character isn't 'x' or 'X', the string is interpreted as an octal integer. If the first character is '0' and the second character is 'x' or 'X', the string is interpreted as a hexadecimal integer. If the first character is '1' through '9', the string is interpreted as a decimal integer. The letters 'a' through 'z' (or 'A' through 'Z') are assigned the values 10 through 35; only letters whose assigned values are less than base are permitted. The first character outside the range of the base stops the scan. For example, if base is 0 and the first character scanned is '0', an octal integer is assumed and an '8' or '9' character stops the scan.

Requirements

Routine Required header
strtoll, _strtoll_l <stdlib.h>
wcstoll, _wcstoll_l <stdlib.h> or <wchar.h>

For more compatibility information, see Compatibility.

See also

Data conversion
Locale
localeconv
setlocale, _wsetlocale
String to numeric value functions
strtod, _strtod_l, wcstod, _wcstod_l
strtol, wcstol, _strtol_l, _wcstol_l
strtoul, _strtoul_l, wcstoul, _wcstoul_l
atof, _atof_l, _wtof, _wtof_l