curs_window(3x) curs_window(3x)
newwin, delwin, mvwin, subwin, derwin, mvderwin, dupwin,
wsyncup, syncok, wcursyncup, wsyncdown - create curses
windows
#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);
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 memo-
ry associated with it (it does not actually erase the win-
dow'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. 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.
Calling derwin is the same as calling subwin, except that
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) in-
side its parent window. The screen-relative parameters of
the window are not changed. This routine is used to dis-
play 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 whenev-
er 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.
Routines that return an integer return the integer ERR up-
on 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 implementa-
tion
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 in-
side 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 in-
side 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.
If many small changes are made to the window, the wsyncup
option could degrade performance.
Note that syncok may be a macro.
The subwindow functions (subwin, derwin, mvderwin, wsyn-
cup, wsyncdown, wcursyncup, syncok) are flaky, incomplete-
ly 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
may result in slower updates.
The XSI Curses standard, Issue 4 describes these func-
tions.
curses(3x), curs_refresh(3x), curs_touch(3x), curs_vari-
ables(3x)
curs_window(3x)