Ncurses and popen example

main.c

/* install ncurses and compile in the following manner: */
/* gcc -std=c99 -Wpedantic -Wall -lncurses main.c       */

#include <ncurses.h>
#include <stdlib.h>
#include <string.h>

int main()
{
	int height, width, ch;

	FILE *fp;
	WINDOW *win;
	char cmd[100];

	char mesg[] = "Enter command: ";

	/* init ncurses */
	initscr();

	/* disables line buffering */
	cbreak();

	/* disables key echoing */
	noecho();

	/* read function keys (F1, F2...) */
	keypad(stdscr, TRUE);

	/* get height and width of screen */
	getmaxyx(stdscr, height, width);

	/* create a new window */
	win = newwin(height - 2, width - 2, 1, 1);
	scrollok(win, TRUE);
	refresh();

	box(win, 0, 0);
	wrefresh(win);

	while((ch = getch()) != 'q')
	{
		switch(ch)
		{
			case KEY_RESIZE:
				wclear(win);
				clear();
				refresh();
				box(win, 0, 0);
				wrefresh(win);
				break;
			case 'e':
				echo();
				mvwprintw(win, 1, 2, "%s", mesg);
				wrefresh(win);
				wgetstr(win, cmd);
				noecho();
				break;
			case 'r':
				if ((fp = popen(cmd, "r")) != 0) {
					char buffer[BUFSIZ];
					while (fgets(buffer, sizeof(buffer), fp) != 0) {
						wprintw(win, "%s", buffer);
						wrefresh(win);
					}
					pclose(fp);
				}
		}
	}

	endwin();

	return EXIT_SUCCESS;
}