curs_refresh(3X) curs_refresh(3X)
curs_refresh: refresh, wrefresh, wnoutrefresh, doupdate, redrawwin,
wredrawln - refresh curses windows and lines
#include <curses.h>
int refresh(void);
int wrefresh(WINDOW *win);
int wnoutrefresh(WINDOW *win);
int doupdate(void);
int redrawwin(WINDOW *win);
int wredrawln(WINDOW *win, int beg_line, int num_lines);
The refresh and wrefresh routines (or wnoutrefresh and doupdate) must be
called to get any output on the terminal, as other routines merely
manipulate data structures. The routine wrefresh copies the named window
to the physical terminal screen, taking into account what is already
there in order to do optimizations. The refresh routine is the same,
using stdscr as the default window. Unless leaveok has been enabled, the
physical cursor of the terminal is left at the location of the cursor for
that window.
The wnoutrefresh and doupdate routines allow multiple updates with more
efficiency than wrefresh alone. In addition to all the window
structures, curses keeps two data structures representing the terminal
screen: a physical screen, describing what is actually on the screen,
and a virtual screen, describing what the programmer wants to have on the
screen.
The routine wrefresh works by first calling wnoutrefresh, which copies
the named window to the virtual screen, and then calling doupdate, which
compares the virtual screen to the physical screen and does the actual
update. If the programmer wishes to output several windows at once, a
series of calls to wrefresh results in alternating calls to wnoutrefresh
and doupdate, causing several bursts of output to the screen. By first
calling wnoutrefresh for each window, it is then possible to call
doupdate once, resulting in only one burst of output, with fewer total
characters transmitted and less CPU time used. If the win argument to
wrefresh is the global variable curscr, the screen is immediately cleared
and repainted from scratch.
The redrawwin routine indicates to curses that some screen lines are
corrupted and should be thrown away before anything is written over them.
These routines could be used for programs such as editors, which want a
command to redraw some part of the screen or the entire screen. The
routine redrawln is preferred over redrawwin where a noisy communication
line exists and redrawing the entire window could be subject to even more
communication noise. Just redrawing several lines offers the possibility
Page 1
curs_refresh(3X) curs_refresh(3X)
that they would show up unblemished.
All routines return the integer ERR upon failure and an integer value
other than ERR upon successful completion.
The header file <curses.h> automatically includes the header files
<stdio.h> and <unctrl.h>.
Note that refresh and redrawwin may be macros.
curses(3X), curs_outopts(3X)
PPPPaaaaggggeeee 2222 [ Back ]
|
