C++ c16rtomb()

The c16rtomb() function is defined in <cuchar> header file.

c16rtomb() Prototype

size_t c16rtomb(char* s, char16_t c16, mbstate_t* ps);

The c16rtomb() function converts the utf-16 character c16 to its multibyte equivalent and store it in the object pointed to by s.

If s represents a null pointer, the call is equivalent to c16rtomb(buf, u'\0', ps) for some internal buffer buf.

If c16 is the null wide character i.e. u'\0', a null byte is stored.

c16rtomb() Parameters

• s: Pointer to a character array where the multibyte character is to be stored.
• c16: The 16 bit character to convert.
• ps: A pointer to an mbstate_t object used when interpreting the multibyte string.

c16rtomb() Return value

• On success, the c16rtomb() function returns the number of bytes written to the character array pointed to by s.
• On failure, -1 is returned and EILSEQ is stored in errno.

Example: How c16rtomb() function works?

#include <cuchar>
#include <iostream>
using namespace std;

int main()
{
	const char16_t str[] = u"Hello World!";
	char s[50];
	mbstate_t ps{};
	size_t length;
	int j = 0;

	while (str[j])
	{
		length = c16rtomb(s, str[j], &ps);
		if ((length == 0) || (length > 50))
			break;
		for (int i=0; i<length; ++i)
			cout << s[i];
		++j;
	}

	return 0;
}

When you run the program, the output will be:

Hello World!