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wnoutrefresh(3cur) [ultrix man page]

wnoutrefresh(3cur)														wnoutrefresh(3cur)

Name
       wnoutrefresh, doupdate - do efficient refresh

Syntax
       #include <cursesX.h>

       int wnoutrefresh(win)
       WINDOW *win;

       int doupdate()

Description
       The  routine  updates  screens  more efficiently than using the routine by itself.  The routine copies the named window to a data structure
       referred to as the virtual screen (stdscr).  The virtual screen contains what a program intends to display on the physical terminal screen.
       The  routine compares the virtual screen to the physical screen and then does the actual update.  These two routines allow multiple updates
       with more efficiency than

       The routine works by calling and then calling If a programmer wants to output several windows at once, a series of calls to will result	in
       alternating calls to and causing several bursts of output to the screen.  If is called first for each window, only needs to be called once,
       resulting in only one burst of output.  This usually results in fewer total characters being transmitted and less CPU time used.

Return Values
       The and functions return OK on success and ERR on error.

See Also
       wrefresh(3cur)

																wnoutrefresh(3cur)

Check Out this Related Man Page

curs_refresh(3X)														  curs_refresh(3X)

NAME
doupdate, redrawwin, refresh, wnoutrefresh, wredrawln, wrefresh - refresh curses windows and lines SYNOPSIS
#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); DESCRIPTION
The refresh and wrefresh routines (or wnoutrefresh and doupdate) must be called to get actual output to 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 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 phrase "copies the named window to the virtual screen" above is ambiguous. What actually happens is that all touched (changed) lines in the window are copied to the virtual screen. This affects programs that use overlapping windows; it means that if two windows overlap, you can refresh them in either order and the overlap region will be modified only when it is explicitly changed. (But see the section on PORTABILITY below for a warning about exploiting this behavior.) The wredrawln routine indicates to curses that some screen lines are corrupted and should be thrown away before anything is written over them. It touches the indicated lines (marking them changed). The routine redrawwin() touches the entire window. RETURN VALUE
Routines that return an integer return ERR upon failure, and OK (SVr4 only specifies "an integer value other than ERR") upon successful completion. NOTES
Note that refresh and redrawwin may be macros. PORTABILITY
The XSI Curses standard, Issue 4 describes these functions. Whether wnoutrefresh() copies to the virtual screen the entire contents of a window or just its changed portions has never been well-docu- mented in historic curses versions (including SVr4). It might be unwise to rely on either behavior in programs that might have to be linked with other curses implementations. Instead, you can do an explicit touchwin() before the wnoutrefresh() call to guarantee an entire-contents copy anywhere. SEE ALSO
curses(3X), curs_outopts(3X) curs_refresh(3X)
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