curs_window(3)                                     curs_window(3)


NAME
       newwin,  delwin,  mvwin, subwin, derwin, mvderwin, dupwin,
       wsyncup, syncok, wcursyncup,  wsyncdown  -  create  curses
       windows



SYNOPSIS
       #include <curses.h>

       WINDOW *newwin(int nlines, int ncols, int begin_y,
             int begin_x);
       int delwin(WINDOW *win);
       int mvwin(WINDOW *win, int y, int x);
       WINDOW *subwin(WINDOW *orig, int nlines, int ncols,
             int begin_y, int begin_x);
       WINDOW *derwin(WINDOW *orig, int nlines, int ncols,
             int begin_y, int begin_x);
       int mvderwin(WINDOW *win, int par_y, int par_x);
       WINDOW *dupwin(WINDOW *win);
       void wsyncup(WINDOW *win);
       int syncok(WINDOW *win, bool bf);
       void wcursyncup(WINDOW *win);
       void wsyncdown(WINDOW *win);

DESCRIPTION
       Calling newwin creates and returns a pointer to a new win-
       dow with the given number of lines and columns.  The upper
       left-hand  corner of the window is at line begin_y, column
       begin_x.  If either nlines or ncols is zero, they  default
       to  LINES - begin_y and COLS - begin_x.  A new full-screen
       window is created by calling newwin(0,0,0,0).

       Calling delwin deletes the named window, freeing all  mem-
       ory  associated  with  it  (it does not actually erase the
       window's screen image).  Subwindows must be deleted before
       the main window can be deleted.

       Calling mvwin moves the window so that the upper left-hand
       corner is at position (x, y).  If the move would cause the
       window to be off the screen, it is an error and the window
       is not moved.  Moving subwindows is allowed, but should be
       avoided.

       Calling subwin creates and returns a pointer to a new win-
       dow with the given number of lines, nlines,  and  columns,
       ncols.   The  window  is at position (begin_y, begin_x) on
       the screen.  (This position is relative to the screen, and
       not to the window orig.)  The window is made in the middle
       of the window orig, so that changes  made  to  one  window
       will  affect  both  windows.   The subwindow shares memory
       with the window orig.  When using this routine, it is nec-
       essary  to call touchwin or touchline on orig before call-
       ing wrefresh on the subwindow.

       Calling derwin is the same as calling subwin, except  that



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curs_window(3)                                     curs_window(3)


       begin_y and begin_x are relative to the origin of the win-
       dow orig rather than the screen.  There is  no  difference
       between the subwindows and the derived windows.

       Calling  mvderwin  moves  a  derived window (or subwindow)
       inside its parent window.  The screen-relative  parameters
       of  the  window  are not changed.  This routine is used to
       display different parts of the parent window at  the  same
       physical position on the screen.

       Calling  dupwin  creates  an exact duplicate of the window
       win.

       Calling wsyncup touches all locations in ancestors of  win
       that  are changed in win.  If syncok is called with second
       argument TRUE then wsyncup is called  automatically  when-
       ever there is a change in the window.

       The  wsyncdown  routine  touches each location in win that
       has been touched in any of  its  ancestor  windows.   This
       routine  is  called by wrefresh, so it should almost never
       be necessary to call it manually.

       The routine wcursyncup updates the current cursor position
       of  all the ancestors of the window to reflect the current
       cursor position of the window.

RETURN VALUE
       Routines that return an integer  return  the  integer  ERR
       upon failure and OK (SVr4 only specifies "an integer value
       other than ERR") upon successful completion.

       delwin returns the integer ERR upon failure  and  OK  upon
       successful completion.

       Routines that return pointers return NULL on error.

NOTES
       If  many small changes are made to the window, the wsyncup
       option could degrade performance.

       Note that syncok may be a macro.

BUGS
       The subwindow functions (subwin, derwin,  mvderwin,  wsyn-
       cup,  wsyncdown,  wcursyncup,  syncok)  are  flaky, incom-
       pletely implemented, and not well tested.

       The System V curses documentation is  very  unclear  about
       what wsyncup and wsyncdown actually do.  It seems to imply
       that they are only supposed to touch exactly  those  lines
       that are affected by ancestor changes.  The language here,
       and the behavior of the  curses  implementation,  is  pat-
       terned  on the XPG4 curses standard.  The weaker XPG4 spec



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curs_window(3)                                     curs_window(3)


       may result in slower updates.

PORTABILITY
       The XSI Curses standard, Issue  4  describes  these  func-
       tions.

SEE ALSO
       curses(3), curs_refresh(3), curs_touch(3)

















































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