by X. Li

C Ncurses Library
Lib Ncurses

If you have some beginning experience in Unix programming, you may have felt the need of some text user interface operations, such as moving the cursor on the screen, editing user input, using colors, .. Such terminal IO related operations are not portable and not defined in C language. You need to either use the low-level termcap library or the curses library. Using curses/ncurses library is much easier and more portable.

2018-02-25 - James Paul Turner - 3.1.6-1 - Update to MPFR version 3.1.6 - Use autosetup specfile macro for applying patches (patches 1 and 2 applied) - Removed iconv calls, as they were breaking.info files, which are now unicode resolves #1299649 - Other minor cleanups - BuildRequire gcc per https. Using ncurses library To compile your C/C programs using ncurses/curses library you need to include the curses header file. For ncurses, you may include either or ncurses.h. In some systems, you must include ncurses.h. #include To link the programs you need to use the -lcurses or -lncurses option, like.

Contents

Using the library: Installations, header inclusions and link options.
Before and after using ncurses function: Thing you need to do before calling curses functions
Creating windows: Creating windows
Moving the cursor: Move the cursor around the window
Input: Read user input from keyboard
Output: Write text to the window
Using colors and other text attributes: Text colors, highlighting, blinking, ..
Using curses in Xterm: How to cope window resizing by user
An example of complete programs: A typing speed test program by me

Using ncurses library

To compile your C/C++ programs using ncurses/curses library you need to include the curses header file <curses.h>. For ncurses, you may include either <curses.h> or <ncurses.h>. In some systems, you must include <ncurses.h>.

#include <curses.h>

To link the programs you need to use the -lcurses or -lncurses option, like

gcc -lncurses prog.c

This way the program is dynamically linked to the ncurses library. To run it in another computer, the system must have the ncurses library installed. If you want to avoid the trouble, you may have it statically linked. To do that, find the file libncurses.a in /usr/lib and do

gcc prog.c libncurses.a

Most Unix systems have curses or ncurses installed as a default option. To find out if it's installed, you can try man ncurses man curses or go to /usr/lib and /usr/include to list the files.

If you're installing Linux or FreeBSD on your own machine, be sure to install the ncurses-development package in order to do ncurses programming.

Initialization

The very first thing to do: Before you use any other curses routines, the initscr() Lib ncurses

routine must be called first.

initscr();

If your program is going to write to several terminals, you should call newterm instead, which is another story.

One-character-a-time. To disable the buffering of typed characters by the TTY driver and get a character-at-a-time input, you need to call

Cura 2.3.1 download mac installer. I'm looking in to it to see if I can figure out how to fix it, but this change wouldn't be much help on its own. Leaving the code set to scan for only USB Serial devices does cause Cura to skip over the COM port for the Maker Select, but if you change it so that it does check the right COM port, it still can't see the relevant printer.Basically, there's more wrong with the code than just this one line.

cbreak();

No echo. To suppress the automatic echoing of typed characters, you need to call

noecho();

Special keys. In order to capture special keystrokes like Backspace, Delete and the four arrow keys by getch(), you need to call

keypad(stdscr, TRUE);

Before exiting. Before the program is terminated, endwin() must be called to restore the terminal settings.

Windows

A window is a 2-dimensional array of characters representing all or part of a CRT screen. Character input and output should pertain to a specific window.

The default window. A default window called stdscr, which is the size of the terminal screen, is supplied. To use the stdscr window, you don't need to do any initializations. You can also divide the screen to several parts and create a window to represent each part.

Create a new window. The data structure of window is WINDOW, defined in ncurses.h. To declare and create a new window, do

WINDOW * win = newwin(nlines, ncols, y0, x0);

All the 4 parameters are ints. Here nline is the height of the window -- number of lines, ncols is the width -- number of columns of the window. y0 and x0 are the coordinates of the upper left corner of win on the screen -- line y0 and columns x0. You should make sure that the area of the new window is inside the screen.

Height and width of the window. The size of the whole screen can be determined by the two global variables COLUMNS and LINES. y0 and x0 should satisfy

In X window system, the actual xterm size might be changed leaving these two variables obslete. In this case you should use the macro void getmaxyx(WINDOW *, int y, int x) to get the size of the screen.

No overlapping. Windows cannot overlap with each other. Therefore you have two options: only use stdscr and no other windows, or create several non-overlapping windows but do not use stdscr.

Refresh. If you make some change to a window, such as printing something or moving the cursor, the effect is not shown on the screen until you call the wrefresh() function

Clear window. To erase everything written in the window win, call wrefresh(win). refresh() is equivalent to wrefresh(stdscr).

Delete window. If a window win is no longer needed, and you're going to create new windows to overlap it, you should call delwin(win) to delete the window (release the memory it is using).

Moving the cursor

The position of the cursor on the screen is important because it is default beginning place for most output functions. The cursor also shows the user where the input is expected.

To move the cursor to a new position on a window, use the function int wmove(WINDOW *win, int y, int x)

wmove(win, y, x);

where (x, y) are the coordinates of the new position in the window. If the window has nlines lines and ncolumns columns, then

Refresh. The actual cursor motion is not shown on the screen untill you do a wrefresh(win).

move(y, x) is equivalent to the wmove(stdscr, y, x).

Input

To read a character from stdscr, use the function int getch(void). No echoing. If you have called noecho(), the character ch will not be printed on the screen, otherwise it will. Disabling automatic echoing gives you more control over the user interface.

No buffering. If you have called cbreak(void) each key the user hits is returned immediately by getch(). Otherwise the keys hit by the user are queued until a newline is read. Then calls to getch() take characters from the queue in FIFO manner until the queue is empty and the next whole line is read.

No delaying. Usually a call to getch() wai