If I have c1, c2 as char variables (such that c1c2 would be the byte sequences for the UTF-8 character), how do I create and print the UTF-8 character?
Similarly for the 3 and 4 byte UTF-8 characters?
I've been trying all kinds of approaches with mbstowcs() but I just can't get it to work.
I managed to write a working example.
When c1 is '\xce' and c2 is '\xb8', the result is θ.
It turns out that I have to call setlocale before using mbstowcs.
#include <stdlib.h>
#include <stdio.h>
#include <locale.h>
int main()
{
char* localeInfo = setlocale(LC_ALL, "en_US.utf8");
printf("Locale information set to %s\n", localeInfo);
const char c1 = '\xce';
const char c2 = '\xb8';
int byteCount = 2;
char* mbS = (char*) malloc(byteCount + 1);
mbS[0] = c1;
mbS[1] = c2;
mbS[byteCount] = 0; //null terminator
printf("Directly using printf: %s\n", mbS);
int requiredSize = mbstowcs(NULL, mbS, 0);
printf("Output size including null terminator is %d\n\n", requiredSize +1);
wchar_t *wideOutput = (wchar_t *)malloc( (requiredSize +1) * sizeof( wchar_t ));
int len = mbstowcs(wideOutput , mbS, requiredSize +1 );
if(len == -1){
printf("Failed conversion!");
}else{
printf("Converted %d character(s). Result: %ls\n", len, wideOutput );
}
return 0;
}
Output:
Locale information set to en_US.utf8
Directly using printf: θ
Output size including null terminator is 2
Converted 1 character(s). Result: θ
For 3 or 4 byte utf8 characters, one can use a similar approach.
If I have c1, c2 as char variables (such that c1c2 would be the byte sequences for the UTF-8 character), how do I create and print the UTF-8 character?
They are already an UTF-8 character. You would just print them.
putchar(c1);
putchar(c2);
It's up to your terminal or whatever device you are using to display the output to properly understand and render the UTF-8 encoding. This is unrelated to encoding used by your program and unrelated to wide characters.
Similarly for the 3 and 4 byte UTF-8 characters?
You would output them.
If your terminal or the device you are sending the bytes to does not understand UTF-8 encoding, then you have to convert the bytes to something the device understands. Typically, you would use an external library for that, like iconv. Alternatively, you could setlocale("C.utf-8") then convert your bytes to wchar_t, then setlocale("C.your_target_encoding") and then convert the bytes to that encoding or output the bytes with %ls. All %ls does (on common systems) is it converts the string back to multibyte and then outputs it. Wide stream outputting to terminal does the same, first converts, then outputs.
