Printing International Fonts w/o changing console fonts

[ruzip]

This one works, but is changing the whole console font and size.


Is there a windows way similar to how Linux does it w/o any font change?


#include <stdio.h>
#include <windows.h>

int main()
{
HANDLE console = GetStdHandle(STD_OUTPUT_HANDLE);
CONSOLE_FONT_INFOEX font;
font.cbSize = sizeof(CONSOLE_FONT_INFOEX);
GetCurrentConsoleFontEx(console, FALSE, &font);
wcscpy(font.FaceName, L"Microsoft YaHei");
SetCurrentConsoleFontEx(console, FALSE, &font);

printf("你好世界\n");

return 0;
}

[LukeProducts]

The Windows console is inherently different from the Linux terminal, and changing font settings in Windows is more involved due to the different APIs and system architecture. The code snippet you provided is indeed changing the console font and size, and unfortunately, there is no direct equivalent to the Linux method on Windows without changing the font.

However, if you're developing a Windows application and want to display Unicode characters without changing the console font, you may want to consider using a GUI library or framework instead, such as Qt or GTK. These libraries allow you to create graphical applications that can display text in various languages without affecting the console settings.

[kigar64551]

@maxim2511

I think mixing Win32 API functions and C/C++ Runtime functions like this can give "unexpected" results 😨

That's because the Win32 API SetConsoleOutputCP(CP_UTF8) only tells the terminal to interpret the given bytes as UTF-8, but there is absolutely no guarantee that C/C++ functions like std::cout, std::wcout, puts(), putws(), printf() or wprintf() will actually write UTF-8 data to the stdout. Also, do not rely on any of those C/C++ functions to pass through the given string to stdout in a "1:1" fashion!

Spoiler: They don't always do 😕


So, here is the proper pure Win32 API (no CRT) solution:

#include <Windows.h>

int main()
{
	const wchar_t *const text = L"\x0393\x03b9\x03ac\x03bd\x03b7\x03c2 \x0392\x03b1\x03c1\x03bf\x03c5\x03c6\x03ac\x03ba\x03b7\x03c2"; //Γιάνης Βαρουφάκης
	SetConsoleOutputCP(CP_UTF8);
	char *utf8_text = utf16_to_utf8(text);
	if (utf8_text)
	{
		DWORD written;
		WriteFile(GetStdHandle(STD_OUTPUT_HANDLE), utf8_text, lstrlenA(utf8_text), &written, NULL);
		LocalFree(utf8_text);
	}
}

We use a little helper function to convert from UTF-16 (wchar_t) to UTF-8:

char* utf16_to_utf8(const wchar_t *const input)
{
	int buff_size = WideCharToMultiByte(CP_UTF8, 0, input, -1, NULL, 0, NULL, NULL);
	if (buff_size > 0)
	{
		char *buffer = (char*)LocalAlloc(LPTR, buff_size);
		if (buffer)
		{
			int result = WideCharToMultiByte(CP_UTF8, 0, input, -1, buffer, buff_size, NULL, NULL);
			if ((result > 0) && (result <= buff_size))
			{
				return buffer;
			}
			LocalFree(buffer);
		}
	}
	return NULL;
}

You can also write UTF-16 to the terminal directly via WriteConsoleW(), but stdout-redirection to a file will not work this way:

int main()
{
	const wchar_t *const text = L"\x0393\x03b9\x03ac\x03bd\x03b7\x03c2 \x0392\x03b1\x03c1\x03bf\x03c5\x03c6\x03ac\x03ba\x03b7\x03c2"; //Γιάνης Βαρουφάκης
	DWORD written;
	WriteConsoleW(GetStdHandle(STD_OUTPUT_HANDLE), text, lstrlenW(text), &written, NULL);
}

In fact, I would recommend something like:

BOOL write_text(HANDLE handle, const wchar_t *const text)
{
	BOOL result = FALSE;
	DWORD written;
	if (GetFileType(handle) == FILE_TYPE_CHAR) // <-- is our handle connected to a terminal?
	{
		result = WriteConsoleW(handle, text, lstrlenW(text), &written, NULL);
	}
	else
	{
		char *const utf8_text = utf16_to_utf8(text);
		if (utf8_text)
		{
			result = WriteFile(handle, utf8_text, lstrlenA(utf8_text), &written, NULL);
			LocalFree(utf8_text);
		}
	}
	return result;
}

Alternatively, here is the pure C/C++ solution (using some MSVC-specific extensions):

#include <cstdio>
#include <iostream>
#include <io.h>
#include <fcntl.h>

int main()
{
	const wchar_t *const text = L"\x0393\x03b9\x03ac\x03bd\x03b7\x03c2 \x0392\x03b1\x03c1\x03bf\x03c5\x03c6\x03ac\x03ba\x03b7\x03c2"; //Γιάνης Βαρουφάκης
	_setmode(_fileno(stdout), _O_U8TEXT); // <-- note: you could use _O_U16TEXT instead here
	_putws(text);
	std::wcout << text << std::endl;
}

Yes, functions like std::wcout or putws() implicitly convert from UTF-16 to UTF-8, if the file mode was set accordingly!


Note: I have escaped all non-ASCII characters in the string literal, because otherwise there is yet another pitfall – the character encoding in which the C/C++ source code file is stored, vs. the character encoding that the C/C++ compiler assumes 🙄

(As others have pointed out, all of this can still be screwed up, if the selected console font doesn't support the required characters!)