I'm writing an ncurses program and am trying to make it respond correctly to terminal resizing. While I can read the terminal dimensions correctly in my program, ncurses doesn't seem to deal with new dimensions correctly. Here's a (somewhat lengthy) sample program:

#include <ncurses.h>
#include <string.h>
#include <signal.h>
#include <sys/ioctl.h>

void handle_winch(int sig){

    struct winsize w;
    ioctl(0, TIOCGWINSZ, &w);
    COLS = w.ws_col;
    LINES = w.ws_row;

    wresize(stdscr, LINES, COLS);
    clear();

    mvprintw(0, 0, "COLS = %d, LINES = %d", COLS, LINES);
    for (int i = 0; i < COLS; i++)
        mvaddch(1, i, '*');

    refresh();
}

int main(int argc, char *argv[]){

    initscr();

    struct sigaction sa;
    memset(&sa, 0, sizeof(struct sigaction));
    sa.sa_handler = handle_winch;
    sigaction(SIGWINCH, &sa, NULL);

    while(getch() != 27) {}

    endwin();
    return 0;
}

If you run it, you can see that the terminal dimensions are correctly retrieved. But the second line, which is supposed to draw *-characters across the screen, doesn't work. Try resizing the window horizontally to make it larger, the line of *s will not get larger.

What's the problem here? I'm aware that one can temporarily leave curses mode, but I'd prefer a cleaner solution. Thanks!