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curses(3curses)

curs_outopts(3curses)






       curs_refresh(3curses)                          curs_refresh(3curses)


       NAME
             curs_refresh: refresh, wrefresh, wnoutrefresh, doupdate,
             redrawwin, wredrawln - refresh curses windows and lines

       SYNOPSIS
             cc [flag . . .] file -lcurses [library . . .]
             #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 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.


                           Copyright 1994 Novell, Inc.               Page 1













      curs_refresh(3curses)                          curs_refresh(3curses)


            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 that they would show up unblemished.

         Return Values
            All routines return the integer ERR upon failure and an
            integer value other than ERR upon successful completion.

      REFERENCES
            curses(3curses), curs_outopts(3curses)

      NOTICES
            The header file curses.h automatically includes the header
            files stdio.h and unctrl.h.

            Note that refresh and redrawwin may be macros.


























                          Copyright 1994 Novell, Inc.               Page 2








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