Printing out Korean in console C++ - c++

I am having trouble with printing out korean.
I have tried various methods with no avail.
I have tried
1.
cout << "한글" << endl;
2.
wcout << "한글" << endl;
3.
wprintf(L"한글\n");
4.
setlocale(LC_ALL, "korean");
wprintf("한글");
and more. But all of those prints "한글".
I am using MinGW compiler, and my OS is windows 7.
P.S Strangely Java prints out Korean fine,
String kor = "한글";
System.out.println(kor);
works.

Set the console codepage to utf-8 before printing the text
::SetConsoleOutputCP(65001)

Since you are using Windows 7 you can use WriteConsoleW which is part of the windows API. #include <windows.h> and try the following code:
DWORD numCharsToWrite = str.length();
LPDWORD numCharsWritten = NULL;
WriteConsoleW(GetStdHandle(STD_OUTPUT_HANDLE), str.c_str(), numCharsToWrite, numCharsWritten, NULL);
where str is the is a std::wstring
More on WriteConsoleW: https://msdn.microsoft.com/en-us/library/windows/desktop/ms687401%28v=vs.85%29.aspx
After having tried other methods this worked for me.

Problem is that there are a lot of places where this could be broken.
Here is answer I've posted some time ago (covers Korean). Answear is for MSVC, but same applies to MinGW (compiler switches are different, locale name may be different).
Here are 5 traps which makes this hard:
Source code encoding. Source has to use encoding which supports all required characters. Nowadays UTF-8 is recommended. It is best to make sure your editor (IDE) is properly configure to enforce source encoding.
You have to inform compiler what is encoding of source file. For gcc it is: -finput-charset=utf-8 (it is default)
Encoding used by executable. You have to define what kind of encoding string literals should be encode in final executable. This encoding should also cover required characters. Here UTF-8 is also the best. Gcc option is -fexec-charset=utf-8
When you run application you have to inform standard library what kind of encoding your string literals are define in or what encoding in program logic is used. So somewhere in your code at beginning of execution you need something like this (here UTF-8 is enforced):
std::locale::global(std::locale{".utf-8"});
and finally you have to instruct stream what kind of encoding it should use. So for std::cout and std::cin you should set locale which is default for the system:
auto streamLocale = std::locale{""};
// this impacts date/time/floating point formats, so you may want tweak it just to use sepecyfic encoding and use C-loclae for formating
std::cout.imbue(streamLocale);
std::cin.imbue(streamLocale);
After this everything should work as desired without code which explicitly does conversions.
Since there are 5 places to make mistake, this is reason people have trouble with it and internet is full of "hack" solutions.
Note that if system is not configured for support all needed characters (for example wrong code page is set) then with thsi configuration characters which could not be converted will be replaced with question mark.

Related

How do I use system("chcp 936") in my dialog based project?

The code below is supposed to convert a wstring "!" to a string and output it,
setlocale(LC_ALL, "Chinese_China.936");
//system("chcp 936");
std::wstring ws = L"!";
string as((ws.length()) * sizeof(wchar_t), '-');
auto rs = wcstombs((char*)as.c_str(), ws.c_str(), as.length());
as.resize(rs);
cout << rs << ":" << as << endl;
If you run it without system("chcp 936");, the converted string is "£¡" rather than "!". If with system("chcp 936");, the result is correct in a console project.
But on my Dialog based project, system("chcp 936")is useless, even if it's workable, I can't use it, because it would popup a console.
PS: the IDE is Visual Studio 2019, and my source code is stored as in UTF-8 with signature.
My operation system language is English and language for non-unicode programs is English (United States).
Edit: it's interesting, even with "en-US" locale, "!" can be converted to an ASCII "!".
But I don't get where "£¡" I got in the dialog based project.
There are two distinct points to considere with locales:
you must tell the program what charset should be used when converting unicode characters to plain bytes (this is the role for setlocale)
you must tell the terminal what charset it should render (this is the role for chcp in Windows console)
The first point depends on the language and optionaly libraries that you use in your program (here the C++ language and Standard Library)
The second point depends on the console application and underlying system. Windows console uses chcp, and you will find in that other post how you can configure xterm in a Unix-like system.
I found out the cause, the wstring-to-string conversion is no problem, the problem was I used CA2T to convert the Chinese punctuation mark and it failed. So it showed "£¡" in the UI finally.
By means of mbstowcs, the counterpart of wcstombs, it would work.

Can't display 'ä' in GLFW window title

glfwSetWindowTitle(win, "Nämen");
Becomes "N?men", where '?' is in a little black, twisted square, indicating that the character could not be displayed.
How do I display 'ä'?
If you want to use non-ASCII letters in the window title, then the string has to be utf-8 encoded.
GLFW: Window title:
The window title is a regular C string using the UTF-8 encoding. This means for example that, as long as your source file is encoded as UTF-8, you can use any Unicode characters.
If you see a little black, twisted square then this indicates that the ä is encoded with some iso encoding that is not UTF-8, maybe something like latin1. To fix this you need to open it in the editor in which you can change the encoding of the file, change it to uft-8 (without BOM) and fix the ä in the title.
It seems like the GLFW implementation does not work according to the specification in this case. Probably the function still uses Latin-1 instead of UTF-8.
I had the same problem on GLFW 3.3 Windows 64 bit precompiled binaries and fixed it like this:
SetWindowTextA(glfwGetWin32Window(win),"Nämen")
The issue does not lie within GLFW but within the compiler. Encodings are handled by the major compilers as follows:
Good guy clang assumes that every file is encoded in UTF-8
Trusty gcc checks the system's settings1 and falls back on UTF-8, when it fails to determine one.
MSVC checks for BOM and uses the detected encoding; otherwise it assumes that file is encoded using the users current code page2.
You can determine your current code page by simply running chcp in your (Windows) console or PowerShell. For me, on a fresh install of Windows 11, it yields "850" (language: English; keyboard: German), which stands for Code Page 850.
To fix this issue you have several solutions:
Change your systems code page. Arguably the worst solution.
Prefix your strings with u8, escape all unicode literals and convert the string to wide char before passing Win32 functions; e.g.:
const char* title = u8"\u0421\u043b\u0430\u0432\u0430\u0020\u0423\u043a\u0440\u0430\u0457\u043d\u0456\u0021";
// This conversion is actually performed by GLFW; see footnote ^3
const int l = MultiByteToWideChar(CP_UTF8, 0, title, -1, NULL, 0);
wchar_t* buf = _malloca(l * sizeof(wchar_t));
MultiByteToWideChar(CP_UTF8, 0, title, -1, buf, l);
SetWindowTextW(hWnd, buf);
_freea(buf);
Save your source files with UTF-8 encoding WITH BOM. This allows you to write your strings without having to escape them. You'll still need to convert the string to a wide char string using the method seen above.
Specify the /utf-8 flag when compiling; this has the same effect as the previous solution, but you don't need the BOM anymore.
The solutions stated above still require you convert your good and nice string to a big chunky wide string.
Another option would be to provide a manifest4 with the activeCodePage set to UTF-8. This way all Win32 functions with the A-suffix (e.g. SetWindowTextA) now accept and properly handle UTF-8 strings, if the running system is at least or newer than Windows Version 1903.
TL;DR
Compile your application with the /utf-8 flag active.
IMPORTANT: This works for the Win32 APIs. This doesn't let you magically write Unicode emojis to the console like a hipster JS developer.
1 I suppose it reads the LC_ALL setting on linux. In the last 6 years I have never seen a distribution, that does NOT specify UTF-8. However, take this information with a grain of salt; I might be entirely wrong on how gcc handles this now.
2 If no byte-order mark is found, it assumes that the source file is encoded in the current user code page [...].
3 GLFW performs the conversion as seen here.
4 More about Win32 ANSI-APIs, Manifest and UTF-8 can be found here.

How to initialize or assign 中文 to wstring?

I tried to use L"string", but it doesn't work.
#include <iostream>
using namespace std;
int main(){
wstring wstr = L"你好";//[Error] converting to execution character set: Illegal byte sequence
wcout<<wstr<<endl;
}
Use wcin and input 中文 works fine.
#include <iostream>
using namespace std;
int main(){
wstring wstr;
wcin>>wstr;//Input Chinese is OK
wcout<<wstr<<endl;
}
How to initialize or assign 中文 to wstring?
Edit: I tried some online compilers. They all can compile but all output "??".
e.g. cpp.sh jdoodle onlinegdb repl.it
Edit 2: I installed g++ i868 MinGW-W64 8.1.0. Use Visual Studio to save the cpp file as utf8 format. Then use command line to compile it. It still output nothing.
Your compiler clearly doesn't like Unicode characters in its source files. Try initializing your string with Unicode escapes, instead:
wstring wstr = L"\u4E2D\u6587"; // These MAY be the correct codes.
Where 4E2D and 6587 are replaced with the actual hexadecimal values for the characters you want. (Sorry, but I don't have access to a full Unicode table for Chinese characters: I tried pasting them into my compiler, and these are the values it gave me on translating.)
The Unicode values given are for the character string in your question (中文); for the (different - 你好) one in your posted code, use L"\u4F60\u597D".
Also see the answer by #MarekR.
This must be configuration issue!
Apparently your compiler uses different encoding then your file is written in!
Since you are using Windows most probably encoding of file on your machine is not UTF-8 (end you have copied this file to Linux), but something else.
Since gcc is more Linux friendly it may expect UTF-8 and you have an conflict.
This is common problem, since Windows for a long time did maintain some backward compatibility with DOS (where only single byte characters where allowed and system used code pages for respective languages).
As you can see here, most compilers with default settings do not have a problem with code which uses Chinese characters.
I do not see TCM-GCC 4.9.2 compiler on godbolt, but it is not very old gcc after all.
I recommend ensure that code is written in UTF-8 and compiler will treat sources as UTF-8 encoded.
Edit: Adding std::locale::global(std::locale("")); made your code properly displaying this string on godbolt.
I tried in Visual Studio. It works(outputs "你好") if I saved my C++ file to either Unicode or utf8 format. Can you try saving your c++ file to either Unicode or utf8?

C++ output Unicode in variable

I'm trying to output a string containing unicode characters, which is received with a curl call. Therefore, I'm looking for something similar to u8 and L options for literal strings, but than applicable for variables. E.g.:
const char *s = u8"\u0444";
However, since I have a string containing unicode characters, such as:
mit freundlichen Grüßen
When I want to print this string with:
cout << UnicodeString << endl;
it outputs:
mit freundlichen Gr??en
When I use wcout, it returns me:
mit freundlichen Gren
What am I doing wrong and how can I achieve the correct output. I return the output with RapidJSON, which returns the string as:
mit freundlichen Gr��en
Important to note, the application is a CGI running on Ubuntu, replying on browser requests
If you are on Windows, what I would suggest is using Unicode UTF-16 at the Windows boundary.
It seems to me that on Windows with Visual C++ (at least up to VS2015) std::cout cannot output UTF-8-encoded-text, but std::wcout correctly outputs UTF-16-encoded text.
This compilable code snippet correctly outputs your string containing German characters:
#include <fcntl.h>
#include <io.h>
#include <iostream>
int main()
{
_setmode(_fileno(stdout), _O_U16TEXT);
// ü : U+00FC
// ß : U+00DF
const wchar_t * text = L"mit freundlichen Gr\u00FC\u00DFen";
std::wcout << text << L'\n';
}
Note the use of a UTF-16-encoded wchar_t string.
On a more general note, I would suggest you using the UTF-8 encoding (and for example storing text in std::strings) in your cross-platform C++ portions of code, and convert to UTF-16-encoded text at the Windows boundary.
To convert between UTF-8 and UTF-16 you can use Windows APIs like MultiByteToWideChar and WideCharToMultiByte. These are C APIs, that can be safely and conveniently wrapped in C++ code (more details can be found in this MSDN article, and you can find compilable C++ code here on GitHub).
On my system the following produces the correct output. Try it on your system. I am confident that it will produce similar results.
#include <string>
#include <iostream>
using namespace std;
int main()
{
string s="mit freundlichen Grüßen";
cout << s << endl;
return 0;
}
If it is ok, then this points to the web transfer not being 8-bit clean.
Mike.
containing unicode characters
You forgot to specify which unicode encoding does the string contain. There is the "narrow" UTF-8, which can be stored in a std::string and printed using std::cout, as well as wider variants, which can't. It is crucial to know which encoding you're dealing with. For the remainder of my answer, I'm going to assume you want to use UTF-8.
When I want to print this string with:
cout << UnicodeString << endl;
EDIT:
Important to note, the application is a CGI running on Ubuntu, replying on browser requests
The concerns here are slightly different from printing onto a terminal.
You need to set the Content-Type response header appropriately or else the client cannot know how to interpret the response. For example Content-Type: application/json; charset=utf-8.
You still need to make sure that the source string is in fact the correct encoding corresponding to the header. See the old answer below for overview.
The browser has to support the encoding. Most modern browsers have had support for UTF-8 a long time now.
Answer regarding printing to terminal:
Assuming that
UnicodeString indeed contains an UTF-8 encoded string
and that the terminal uses UTF-8 encoding
and the font that the terminal uses has the graphemes that you use
the above should work.
it outputs:
mit freundlichen Gr??en
Then it appears that at least one of the above assumptions don't hold.
Whether 1. is true, you can verify by inspecting the numeric value of each code unit separately and comparing it to what you would expect of UTF-8. If 1. isn't true, then you need to figure out what encoding does the string actually use, and either convert the encoding, or configure the terminal to use that encoding.
The terminal typically, but not necessarily, uses the system native encoding. The first step of figuring out what encoding your terminal / system uses is to figure out what terminal / system you are using in the first place. The details are probably in a manual.
If the terminal doesn't use UTF-8, then you need to convert the UFT-8 string within your program into the character encoding that the terminal does use - unless that encoding doesn't have the graphemes that you want to print. Unfortunately, the standard library doesn't provide arbitrary character encoding conversion support (there is some support for converting between narrow and wide unicode, but even that support is deprecated). You can find the unicode standard here, although I would like to point out that using an existing conversion implementation can save a lot of work.
In the case the character encoding of the terminal doesn't have the needed grapehemes - or if you don't want to implement encoding conversion - is to re-configure the terminal to use UTF-8. If the terminal / system can be configured to use UTF-8, there should be details in the manual.
You should be able to test if the font itself has the required graphemes simply by typing the characters into the terminal and see if they show as they should - although, this test will also fail if the terminal encoding does not have the graphemes, so check that first. Manual of your terminal should explain how to change the font, should it be necessary. That said, I would expect üß to exist in most fonts.

Can't read unicode (japanese) from a file

Hi I have a file containing japanese text, saved as unicode file.
I need to read from the file and display the information to the stardard output.
I am using Visual studio 2008
int main()
{
wstring line;
wifstream myfile("D:\sample.txt"); //file containing japanese characters, saved as unicode file
//myfile.imbue(locale("Japanese_Japan"));
if(!myfile)
cout<<"While opening a file an error is encountered"<<endl;
else
cout << "File is successfully opened" << endl;
//wcout.imbue (locale("Japanese_Japan"));
while ( myfile.good() )
{
getline(myfile,line);
wcout << line << endl;
}
myfile.close();
system("PAUSE");
return 0;
}
This program generates some random output and I don't see any japanese text on the screen.
Oh boy. Welcome to the Fun, Fun world of character encodings.
The first thing you need to know is that your console is not unicode on windows. The only way you'll ever see Japanese characters in a console application is if you set your non-unicode (ANSI) locale to Japanese. Which will also make backslashes look like yen symbols and break paths containing european accented characters for programs using the ANSI Windows API (which was supposed to have been deprecated when Windows XP came around, but people still use to this day...)
So first thing you'll want to do is build a GUI program instead. But I'll leave that as an exercise to the interested reader.
Second, there are a lot of ways to represent text. You first need to figure out the encoding in use. Is is UTF-8? UTF-16 (and if so, little or big endian?) Shift-JIS? EUC-JP? You can only use a wstream to read directly if the file is in little-endian UTF-16. And even then you need to futz with its internal buffer. Anything other than UTF-16 and you'll get unreadable junk. And this is all only the case on Windows as well! Other OSes may have a different wstream representation. It's best not to use wstreams at all really.
So, let's assume it's not UTF-16 (for full generality). In this case you must read it as a char stream - not using a wstream. You must then convert this character string into UTF-16 (assuming you're using windows! Other OSes tend to use UTF-8 char*s). On windows this can be done with MultiByteToWideChar. Make sure you pass in the right code page value, and CP_ACP or CP_OEMCP are almost always the wrong answer.
Now, you may be wondering how to determine which code page (ie, character encoding) is correct. The short answer is you don't. There is no prima facie way of looking at a text string and saying which encoding it is. Sure, there may be hints - eg, if you see a byte order mark, chances are it's whatever variant of unicode makes that mark. But in general, you have to be told by the user, or make an attempt to guess, relying on the user to correct you if you're wrong, or you have to select a fixed character set and don't attempt to support any others.
Someone here had the same problem with Russian characters (He's using basic_ifstream<wchar_t> wich should be the same as wifstream according to this page). In the comments of that question they also link to this which should help you further.
If understood everything correctly, it seems that wifstream reads the characters correctly but your program tries to convert them to whatever locale your program is running in.
Two errors:
std::wifstream(L"D:\\sample.txt");
And do not mix cout and wcout.
Also check that your file is encoded in UTF-16, Little-Endian. If not so, you will be in trouble reading it.
wfstream uses wfilebuf for the actual reading and writing of the data. wfilebuf defaults to using a char buffer internally which means that the text in the file is assumed narrow, and converted to wide before you see it. Since the text was actually wide, you get a mess.
The solution is to replace the wfilebuf buffer with a wide one.
You probably also need to open the file as binary.
const size_t bufsize = 128;
wchar_t buffer[bufsize];
wifstream myfile("D:\\sample.txt", ios::binary);
myfile.rdbuf()->pubsetbuf(buffer, 128);
Make sure the buffer outlives the stream object!
See details here: http://msdn.microsoft.com/en-us/library/tzf8k3z8(v=VS.80).aspx