1curs_window(3X)                                                curs_window(3X)
2
3
4

NAME

6       newwin, delwin, mvwin, subwin, derwin, mvderwin, dupwin, wsyncup,
7       syncok, wcursyncup, wsyncdown - create curses windows
8

SYNOPSIS

10       #include <curses.h>
11
12       WINDOW *newwin(
13             int nlines, int ncols,
14             int begin_y, int begin_x);
15       int delwin(WINDOW *win);
16       int mvwin(WINDOW *win, int y, int x);
17       WINDOW *subwin(WINDOW *orig,
18             int nlines, int ncols,
19             int begin_y, int begin_x);
20       WINDOW *derwin(WINDOW *orig,
21             int nlines, int ncols,
22             int begin_y, int begin_x);
23       int mvderwin(WINDOW *win, int par_y, int par_x);
24       WINDOW *dupwin(WINDOW *win);
25       void wsyncup(WINDOW *win);
26       int syncok(WINDOW *win, bool bf);
27       void wcursyncup(WINDOW *win);
28       void wsyncdown(WINDOW *win);
29

DESCRIPTION

31   newwin
32       Calling newwin creates and returns a pointer to a new window  with  the
33       given  number  of lines and columns.  The upper left-hand corner of the
34       window is at
35              line begin_y,
36              column begin_x
37
38       If either nlines or ncols is zero, they default to
39              LINES - begin_y and
40              COLS - begin_x.
41
42       A new full-screen window is created by calling newwin(0,0,0,0).
43
44   delwin
45       Calling delwin deletes the named window, freeing all memory  associated
46       with  it  (it does not actually erase the window's screen image).  Sub‐
47       windows must be deleted before the main window can be deleted.
48
49   mvwin
50       Calling mvwin moves the window so that the upper left-hand corner is at
51       position  (x,  y).   If  the  move would cause the window to be off the
52       screen, it is an error and the window is not moved.  Moving  subwindows
53       is allowed, but should be avoided.
54
55   subwin
56       Calling  subwin  creates and returns a pointer to a new window with the
57       given number of lines, nlines, and columns, ncols.  The  window  is  at
58       position (begin_y, begin_x) on the screen.  The subwindow shares memory
59       with the window orig, so that changes made to one  window  will  affect
60       both  windows.  When using this routine, it is necessary to call touch‐
61       win or touchline on orig before calling wrefresh on the subwindow.
62
63   derwin
64       Calling derwin is the same as calling subwin, except that  begin_y  and
65       begin_x  are  relative to the origin of the window orig rather than the
66       screen.  There is no difference between the subwindows and the  derived
67       windows.
68
69       Calling  mvderwin moves a derived window (or subwindow) inside its par‐
70       ent window.  The screen-relative  parameters  of  the  window  are  not
71       changed.  This routine is used to display different parts of the parent
72       window at the same physical position on the screen.
73
74   dupwin
75       Calling dupwin creates an exact duplicate of the window win.
76
77   wsyncup
78       Calling wsyncup touches all locations in  ancestors  of  win  that  are
79       changed  in  win.   If  syncok is called with second argument TRUE then
80       wsyncup is called automatically whenever there is a change in the  win‐
81       dow.
82
83   wsyncdown
84       The  wsyncdown  routine  touches  each  location  in  win that has been
85       touched in any of its ancestor windows.  This routine is called by wre‐
86       fresh, so it should almost never be necessary to call it manually.
87
88   wcursyncup
89       The  routine  wcursyncup updates the current cursor position of all the
90       ancestors of the window to reflect the current cursor position  of  the
91       window.
92

RETURN VALUE

94       Routines that return an integer return the integer ERR upon failure and
95       OK (SVr4 only specifies "an integer value other than  ERR")  upon  suc‐
96       cessful completion.
97
98       Routines that return pointers return NULL on error.
99
100       X/Open defines no error conditions.  In this implementation
101
102       delwin
103            returns  an  error if the window pointer is null, or if the window
104            is the parent of another window.
105
106       derwin
107            returns an error if the parent window pointer is null, or  if  any
108            of  its  ordinates  or dimensions is negative, or if the resulting
109            window does not fit inside the parent window.
110
111       dupwin
112            returns an error if the window pointer is null.
113
114            This implementation also maintains a list of windows,  and  checks
115            that  the pointer passed to delwin is one that it created, return‐
116            ing an error if it was not..
117
118       mvderwin
119            returns an error if the window pointer is null, or if some part of
120            the window would be placed off-screen.
121
122       mvwin
123            returns  an  error if the window pointer is null, or if the window
124            is really a pad, or if some part of the  window  would  be  placed
125            off-screen.
126
127       newwin
128            will  fail if either of its beginning ordinates is negative, or if
129            either the number of lines or columns is negative.
130
131       syncok
132            returns an error if the window pointer is null.
133
134       subwin
135            returns an error if the parent window pointer is null, or  if  any
136            of  its  ordinates  or dimensions is negative, or if the resulting
137            window does not fit inside the parent window.
138
139       The functions which return a window pointer may also fail if  there  is
140       insufficient  memory  for  its data structures.  Any of these functions
141       will fail if the screen has not been initialized, i.e., with initscr or
142       newterm.
143

NOTES

145       If  many small changes are made to the window, the wsyncup option could
146       degrade performance.
147
148       Note that syncok may be a macro.
149

BUGS

151       The subwindow functions (subwin, derwin, mvderwin, wsyncup,  wsyncdown,
152       wcursyncup,  syncok)  are flaky, incompletely implemented, and not well
153       tested.
154
155       The System V curses documentation is very unclear  about  what  wsyncup
156       and  wsyncdown  actually do.  It seems to imply that they are only sup‐
157       posed to touch exactly  those  lines  that  are  affected  by  ancestor
158       changes.  The language here, and the behavior of the curses implementa‐
159       tion, is patterned on the XPG4 curses standard.  The weaker  XPG4  spec
160       may result in slower updates.
161

PORTABILITY

163       The XSI Curses standard, Issue 4 describes these functions.
164

SEE ALSO

166       curses(3X), curs_refresh(3X), curs_touch(3X), curs_variables(3X)
167
168
169
170                                                               curs_window(3X)
Impressum