what is the role of refresh function in ncurses?
 

Hi
as you know some functions like printw write a string into stdscr not curscr
or real screen and some other functions like refresh write changes to stdscr
to scrscr.it means when we use printw real screen should not change.
but when i use printw real screen shows changes immediately without any
need to call refresh function . what is the reason of this problem ?

Most of the ncurses routines simply modify the data structures. The refresh function updates the screen.

For more information check the man page (man 3 refresh).