`malloc` returns a void pointer to the allocated space, or `NULL` if there is insufficient memory available. To return a pointer to a type other than `void`, use a type cast on the return value. The storage space pointed to by the return value is guaranteed to be suitably aligned for storage of any type of object that has an alignment requirement less than or equal to that of the fundamental alignment. (In Visual C++, the fundamental alignment is the alignment that's required for a `double`, or 8 bytes. In code that targets 64-bit platforms, it’s 16 bytes.) Use [_aligned_malloc](../../c-runtime-library/reference/aligned-malloc.md) to allocate storage for objects that have a larger alignment requirement—for example, the SSE types [__m128](../../cpp/m128.md) and `__m256`, and types that are declared by using `__declspec(align(``n``))` where `n` is greater than 8. If `size` is 0, `malloc` allocates a zero-length item in the heap and returns a valid pointer to that item. Always check the return from `malloc`, even if the amount of memory requested is small.

If `mbsrtowcs_s` successfully converts the source string, it puts the size in wide characters of the converted string and the null terminator into `*``pReturnValue`, provided `pReturnValue` is not a null pointer. This occurs even if the `wcstr` argument is a null pointer and lets you determine the required buffer size. Note that if `wcstr` is a null pointer, `count` is ignored.

If `mbsrtowcs_s` encounters a multibyte character that is not valid in the current locale, it puts -1 in `*``pReturnValue`, sets the destination buffer `wcstr` to an empty string, sets `errno` to `EILSEQ`, and returns `EILSEQ`.

If `mbstowcs_s` successfully converts the source string, it puts the size in wide characters of the converted string, including the null terminator, into `*``pReturnValue` (provided `pReturnValue` is not `NULL`). This occurs even if the `wcstr` argument is `NULL` and provides a way to determine the required buffer size. Note that if `wcstr` is `NULL`, `count` is ignored, and `sizeInWords` must be 0.

If `mbstowcs_s` encounters an invalid multibyte character, it puts 0 in `*``pReturnValue`, sets the destination buffer to an empty string, sets `errno` to `EILSEQ`, and returns `EILSEQ`.

Converts a UTC time represented by a `tm``struct` to a UTC time represented by a `time_t` type.

A pointer to the UTC time as a `struct``tm` to convert.

The `_splitpath_s` function breaks a path into its four components. `_splitpath_s` automatically handles multibyte-character string arguments as appropriate, recognizing multibyte-character sequences according to the multibyte code page currently in use. `_wsplitpath_s` is a wide-character version of `_splitpath_s`; the arguments to `_``wsplitpath_s` are wide-character strings. These functions behave identically otherwise

The other main difference between `sprintf_s` and `sprintf` is that `sprintf_s` takes a length parameter specifying the size of the output buffer in characters. If the buffer is too small for the formatted text, including the terminating null, then the buffer is set to an empty string by placing a null character at `buffer``[0]`, and the invalid parameter handler is invoked. Unlike `_snprintf`, `sprintf_s` guarantees that the buffer will be null-terminated unless the buffer size is zero.

`_stat` is equivalent to `_stat64i32`, and `struct``_stat` contains a 64-bit time. This is true unless `_USE_32BIT_TIME_T` is defined, in which case the old behavior is in effect; `_stat` uses a 32-bit time, and `struct``_stat` contains a 32-bit time. The same is true for `_stati64`.

`set` `TZ`=`tzn`[+ | -]`hh`[`:``mm`[`:``ss`] ][`dzn`]

If `wcsrtombs_s` successfully converts the source string, it puts the size in bytes of the converted string, including the null terminator, into `*``pReturnValue` (provided `pReturnValue` is not `NULL`). This occurs even if the `mbstr` argument is `NULL` and provides a way to determine the required buffer size. Note that if `mbstr` is `NULL`, `count` is ignored.

If `wcsrtombs_s` encounters a wide character it cannot convert to a multibyte character, it puts -1 in `*``pReturnValue`, sets the destination buffer to an empty string, sets `errno` to `EILSEQ`, and returns `EILSEQ`.