NCURSES border printing as q, x, when using UTF-8 and PuTTY

Question

I am trying to learn ncurses to add some functionality to my programs however I cannot seem to get my terminal settings to the point where the default ncurses window border shows up as expected.

Here is the output I am getting for a window with a box border:

  lqqqqqqqqk
  x        x
  x        x
  x        x
  mqqqqqqqqj

However I should be getting this:

  ┌────────┐
  │        │
  │        │
  │        │
  └────────┘

The only thing I am able to find that fixes this issue is setting my PuTTY Remove Character Set to be Latin-1 instead of UTF-8, however this messes up all of my other applications including VIM.

There were some related SO questions that I found (1 and 2) however neither of their solutions help me. The only interesting thing I pulled out of the second one is that if I run printf '\342\224\224\342\224\200\342\224\220' in my command line it prints out └─┐ (which is correct...).

Here is the simple program I am using to test this:

 #include <iostream>
 #include <ncurses.h>
 #include <string>
 #include <cstring>

 int main() {
     WINDOW *my_win;
     int startx, starty, width, height;
     int ch;

     initscr();
     cbreak();
     keypad(stdscr, TRUE);
     refresh();

     int height = 5;
     int width = 10;
     my_win = newwin(height, width, 1, 2);
     box(my_win, 0, 0);
     wrefresh(my_win);

     getch();

     endwin();
     return 0;
 }

Any ideas what I could be doing wrong? Thanks!

Answer 1

You're not initializing the locale. Without that, ncurses will assume that it can use the terminal description.

Further reading:

• ncurses manual page, Initialization:

The library uses the locale which the calling program has initialized. That is normally done with setlocale:

setlocale(LC_ALL, "");

If the locale is not initialized, the library assumes that characters are printable as in ISO-8859-1, to work with certain legacy programs. You should initialize the locale and not rely on specific details of the library when the locale has not been setup.

• ncurses manual page, NCURSES_NO_UTF8_ACS:

During initialization, the ncurses library checks for special cases where VT100 line-drawing (and the corresponding alternate character set capabilities) described in the terminfo are known to be missing. Specifically, when running in a UTF-8 locale, the Linux console emulator and the GNU screen program ignore these. Ncurses checks the TERM environment variable for these. For other special cases, you should set this environment variable.