curs_refresh(3X)        LIBRARY FUNCTIONS        curs_refresh(3X)



NAME
     cursrefresh:  refresh,  wrefresh,  wnoutrefresh,  doupdate,
     redrawwin, wredrawln - 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 begline, int numlines);

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 vir-
     tual 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  alternat-
     ing  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  that  they



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curs_refresh(3X)        LIBRARY FUNCTIONS        curs_refresh(3X)



     would show up unblemished.

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

NOTES
     The header file <curses.h> automatically includes the header
     files <stdio.h> and <unctrl.h>.

     Note that refresh and redrawwin may be macros.

SEE ALSO
     curses(3X), cursoutopts(3X).









































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