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curs_overlay(3X) curs_overlay(3X)
NAME
overlay, overwrite, copywin - overlay and manipulate overlapped curses
windows
SYNOPSIS
#include <curses.h>
int overlay(const WINDOW *srcwin, WINDOW *dstwin);
int overwrite(const WINDOW *srcwin, WINDOW *dstwin);
int copywin(const WINDOW *srcwin, WINDOW *dstwin, int sminrow,
int smincol, int dminrow, int dmincol, int dmaxrow,
int dmaxcol, int overlay);
DESCRIPTION
overlay, overwrite
The overlay and overwrite routines overlay srcwin on top of dstwin.
scrwin and dstwin are not required to be the same size; only text where
the two windows overlap is copied. The difference is that overlay is
non-destructive (blanks are not copied) whereas overwrite is
destructive.
copywin
The copywin routine provides a finer granularity of control over the
overlay and overwrite routines. As in the prefresh routine, a
rectangle is specified in the destination window, (dminrow, dmincol)
and (dmaxrow, dmaxcol), and the upper-left-corner coordinates of the
source window, (sminrow, smincol). If the argument overlay is true,
then copying is non-destructive, as in overlay.
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.
X/Open defines no error conditions. In this implementation, copywin,
overlay and overwrite return an error if either of the window pointers
are null, or if some part of the window would be placed off-screen.
NOTES
Note that overlay and overwrite may be macros.
PORTABILITY
The XSI Curses standard, Issue 4 describes these functions (adding the
const qualifiers). It further specifies their behavior in the presence
of characters with multibyte renditions (not yet supported in this
implementation).
SEE ALSO
curses(3X), curs_pad(3X), curs_refresh(3X)
curs_overlay(3X)