Insert a character at the current cursor position in the
    specified window. The insch function acts on the stdscr window.

    Format

      #include  <curses.h>

      int insch  (char ch);

      int winsch  (WINDOW *win, char ch);

1 - Arguments

 win

    A pointer to the window.

 ch

    The character to be inserted.

2 - Description

    After the character is inserted, each character on the line
    shifts to the right, and the last character in the line is
    deleted. For more information, see the scrollok function.

3 - Return Values

    OK                 Indicates success.
    ERR                Indicates that the function makes the screen
                       scroll illegally.