strtol, wcstol, _strtol_l, _wcstol_l
For the latest documentation on Visual Studio 2017 RC, see Visual Studio 2017 RC Documentation.
Convert strings to a long-integer value.
long strtol( const char *nptr, char **endptr, int base ); long wcstol( const wchar_t *nptr, wchar_t **endptr, int base ); long _strtol_l( const char *nptr, char **endptr, int base, _locale_t locale ); long _wcstol_l( const wchar_t *nptr, wchar_t **endptr, int base, _locale_t locale );
Null-terminated string to convert.
Pointer to character that stops scan.
Number base to use.
Locale to use.
strtol returns the value represented in the string
nptr, except when the representation would cause an overflow, in which case it returns
strtol returns 0 if no conversion can be performed.
wcstol returns values analogously to
strtol. For both functions,
errno is set to
ERANGE if overflow or underflow occurs.
See _doserrno, errno, _sys_errlist, and _sys_nerr for more information on these and other return codes.
strtol function converts
nptr to a
strtol stops reading the string
nptr at the first character it cannot recognize as part of a number. This may be the terminating null character, or it may be the first numeric character greater than or equal to
wcstol is a wide-character version of
nptr argument is a wide-character string. These functions behave identically otherwise.
|TCHAR.H routine||_UNICODE & _MBCS not defined||_MBCS defined||_UNICODE defined|
The current locale's
LC_NUMERIC category setting determines recognition of the radix character in
nptr; for more information, see setlocale. The functions without the
_l suffix use the current locale;
_wcstol_l are identical to the corresponding functions without the
_l suffix except that they use the locale passed in instead. For more information, see Locale.
endptr is not
NULL, a pointer to the character that stopped the scan is stored at the location pointed to by
endptr. If no conversion can be performed (no valid digits were found or an invalid base was specified), the value of
nptr is stored at the location pointed to by
nptr to point to a string of the following form:
X }]] [
whitespace may consist of space and tab characters, which are ignored;
digits are one or more decimal digits. The first character that does not fit this form stops the scan. If
base is between 2 and 36, then it is used as the base of the number. If
base is 0, the initial characters of the string pointed to by
nptr are used to determine the base. If the first character is 0 and the second character is not '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 will stop the scan.
|<stdlib.h> or <wchar.h>|
For additional compatibility information, see Compatibility in the Introduction.
See the example for strtod.