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_ltoa_s, _ltow_s

Converts a long integer to a string. These are versions of _ltoa, _ltow with security enhancements as described in Security Features in the CRT.

errno_t _ltoa_s(
    long value,
    char *str,
    size_t sizeOfstr,
    int radix 
);
errno_t _ltow_s(
    long value,
    wchar_t *str,
    size_t sizeOfstr,
    int radix 
);
template <size_t size>
errno_t _ltoa_s(
    long value,
    char (&str)[size],
    int radix 
); // C++ only
template <size_t size>
errno_t _ltow_s(
    long value,
    wchar_t (&str)[size],
    int radix 
); // C++ only

Parameters

  • value
    Number to be converted.

  • str
    Buffer for the resulting string.

  • sizeOfstr
    Size of the str in bytes for _ltoa_s or words for _ltow_s.

  • radix
    Base of value.

Return Value

Zero if the function was successful or an error code.

Remarks

The _ltoa_s function converts the digits of value to a null-terminated character string and stores the result (up to 33 bytes) in str. The radix argument specifies the base of value, which must be in the range 2 – 36. If radix equals 10 and value is negative, the first character of the stored string is the minus sign (–). _ltow_s is a wide character version of _ltoa_s; the second argument of _ltow_s is a wide character strings.

If str is a NULL pointer or sizeOfstr is less than or equal to zero, these functions invoke an invalid parameter handler, as described in Parameter Validation. If execution is allowed to continue, these functions return -1 and set errno to EINVAL or if the value or str out of range of a long integer, these functions return a -1 and set the errno to ERANGE.

In C++, using these functions is simplified by template overloads; the overloads can infer buffer length automatically (eliminating the need to specify a size argument) and they can automatically replace older, non-secure functions with their newer, secure counterparts. For more information, see Secure Template Overloads.

Generic-Text Routine Mappings

Tchar.h routine

_UNICODE and _MBCS not defined

_MBCS defined

_UNICODE defined

_ltot_s

_ltoa_s

_ltoa_s

_ltow_s

Requirements

Routine

Required header

_ltoa_s

<stdlib.h>

_ltow_s

<stdlib.h>

For more compatibility information, see Compatibility in the Introduction.

.NET Framework Equivalent

System::Convert::ToString

See Also

Reference

Data Conversion

_itoa, _i64toa, _ui64toa, _itow, _i64tow, _ui64tow

_ultoa, _ultow

_ultoa_s, _ultow_s