curs_pad(3)
NAME
newpad, subpad, prefresh, pnoutrefresh, pechochar - create
and display curses pads
SYNOPSIS
#include <curses.h> WINDOW *newpad(int nlines, int ncols); WINDOW *subpad(WINDOW *orig, int nlines, int ncols, int begin_y, int begin_x); int prefresh(WINDOW *pad, int pminrow, int pmincol, int sminrow, int smincol, int smaxrow, int smaxcol); int pnoutrefresh(WINDOW *pad, int pminrow, int pmincol, int sminrow, int smincol, int smaxrow, int smaxcol); int pechochar(WINDOW *pad, chtype ch);
DESCRIPTION
The newpad routine creates and returns a pointer to a new
pad data structure with the given number of lines, nlines,
and columns, ncols. A pad is like a window, except that
it is not restricted by the screen size, and is not necessarily associated with a particular part of the screen.
Pads can be used when a large window is needed, and only a
part of the window will be on the screen at one time.
Automatic refreshes of pads (e.g., from scrolling or echoing of input) do not occur. It is not legal to call wrefresh with a pad as an argument; the routines prefresh or
pnoutrefresh should be called instead. Note that these
routines require additional parameters to specify the part
of the pad to be displayed and the location on the screen
to be used for the display.
The subpad routine creates and returns a pointer to a subwindow within a pad with the given number of lines,
nlines, and columns, ncols. Unlike subwin, which uses
screen coordinates, the window is at position (begin_x,
begin_y) on the pad. The window is made in the middle of
the window orig, so that changes made to one window affect
both windows. During the use of this routine, it will
often be necessary to call touchwin or touchline on orig
before calling prefresh.
The prefresh and pnoutrefresh routines are analogous to
wrefresh and wnoutrefresh except that they relate to pads
instead of windows. The additional parameters are needed
to indicate what part of the pad and screen are involved.
pminrow and pmincol specify the upper left-hand corner of
the rectangle to be displayed in the pad. sminrow, smincol, smaxrow, and smaxcol specify the edges of the rectangle to be displayed on the screen. The lower right-hand
corner of the rectangle to be displayed in the pad is calculated from the screen coordinates, since the rectangles
must be the same size. Both rectangles must be entirely
contained within their respective structures. Negative
values of pminrow, pmincol, sminrow, or smincol are
treated as if they were zero.
The pechochar routine is functionally equivalent to a call
to addch followed by a call to refresh, a call to waddch
followed by a call to wrefresh, or a call to waddch followed by a call to prefresh. The knowledge that only a
single character is being output is taken into
consideration and, for non-control characters, a considerable performance gain might be seen by using these routines instead of their equivalents. In the case of
pechochar, the last location of the pad on the screen is
reused for the arguments to prefresh.
RETURN VALUE
Routines that return an integer return 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, and
set errno to ENOMEM.
NOTES
Note that pechochar may be a macro.
PORTABILITY
The XSI Curses standard, Issue 4 describes these functions.