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 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).
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.
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 window 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 necessary to call touchwin or touchline on orig before calling wrefresh on the subwindow.
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.
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 whenever 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, 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
The XSI Curses standard, Issue 4 describes these functions.