curs_window(3x) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | NOTES | BUGS | PORTABILITY | SEE ALSO | COLOPHON

curs_window(3X)                                          curs_window(3X)

NAME         top

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

SYNOPSIS         top

       #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         top

   newwin
       Calling newwin creates and returns a pointer to a new window 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).

       Regardless of the function used for creating a new window (e.g.,
       newwin, subwin, derwin, newpad), rather than a duplicate (with
       dupwin), all of the window modes are initialized to the default
       values.  These functions set window modes after a window is
       created:

              idcok, idlok, immedok, keypad, leaveok, nodelay, scrollok,
              setscrreg, syncok, wbkgdset, wbkgrndset, and wtimeout

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

   mvwin
       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.

   subwin
       Calling subwin creates and returns a pointer to a new window with
       the given number of lines, nlines, and columns, ncols.  The
       window is at position (begin_y, begin_x) on the screen.  The
       subwindow shares memory with the window orig, so that changes
       made to one window will affect both windows.  When using this
       routine, it is necessary to call touchwin or touchline on orig
       before calling wrefresh on the subwindow.

   derwin
       Calling derwin is the same as calling subwin, except that begin_y
       and begin_x are relative to the origin of the window 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.

   dupwin
       Calling dupwin creates an exact duplicate of the window win.

   wsyncup
       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 whenever there is a
       change in the window.

   wsyncdown
       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.

   wcursyncup
       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         top

       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.

       Routines that return pointers return NULL on error.

       X/Open defines no error conditions.  In this implementation

       delwin
            returns an error if the window pointer is null, or if the
            window is the parent of another window.

       derwin
            returns an error if the parent window pointer is null, or if
            any of its ordinates or dimensions is negative, or if the
            resulting window does not fit inside the parent window.

       dupwin
            returns an error if the window pointer is null.

            This implementation also maintains a list of windows, and
            checks that the pointer passed to delwin is one that it
            created, returning an error if it was not..

       mvderwin
            returns an error if the window pointer is null, or if some
            part of the window would be placed off-screen.

       mvwin
            returns an error if the window pointer is null, or if the
            window is really a pad, or if some part of the window would
            be placed off-screen.

       newwin
            will fail if either of its beginning ordinates is negative,
            or if either the number of lines or columns is negative.

       syncok
            returns an error if the window pointer is null.

       subwin
            returns an error if the parent window pointer is null, or if
            any of its ordinates or dimensions is negative, or if the
            resulting window does not fit inside the parent window.

       The functions which return a window pointer may also fail if
       there is insufficient memory for its data structures.  Any of
       these functions will fail if the screen has not been initialized,
       i.e., with initscr or newterm.

NOTES         top

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

       Note that syncok may be a macro.

BUGS         top

       The subwindow functions (subwin, derwin, mvderwin, wsyncup,
       wsyncdown, wcursyncup, syncok) are flaky, incompletely
       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 patterned on the XPG4 curses standard.
       The weaker XPG4 spec may result in slower updates.

PORTABILITY         top

       The XSI Curses standard, Issue 4 describes these functions.

SEE ALSO         top

       curses(3X), curs_refresh(3X), curs_touch(3X), curs_variables(3X)

COLOPHON         top

       This page is part of the ncurses (new curses) project.
       Information about the project can be found at 
       ⟨https://www.gnu.org/software/ncurses/ncurses.html⟩.  If you have
       a bug report for this manual page, send it to
       bug-ncurses-request@gnu.org.  This page was obtained from the
       project's upstream Git mirror of the CVS repository
       ⟨git://ncurses.scripts.mit.edu/ncurses.git⟩ on 2021-06-20.  (At
       that time, the date of the most recent commit that was found in
       the repository was 2021-05-23.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

                                                         curs_window(3X)