What does L do?

Question

What does this do?

const wchar_t *s = L"test";

If wchar_t is two bytes on my machine, then why should we tell the compiler that the string should be treated in a way that each element is long i.e, four bytes in size?

Answer 1

The L means that string is a string of wchar_t characters, rather than the normal string of char characters. I'm not sure where you got the bit about four bytes from.

From the spec section 6.4.5 String literals, paragraph 2:

A character string literal is a sequence of zero or more multibyte characters enclosed in double-quotes, as in "xyz". A wide string literal is the same, except prefixed by the letter L.

And an excerpt from paragraph 5:

For character string literals, the array elements have type char, and are initialized with the individual bytes of the multibyte character sequence; for wide string literals, the array elements have type wchar_t, and are initialized with the sequence of wide characters corresponding to the multibyte character sequence, as defined by the mbstowcs function with an implementation-defined current locale.