# curs_overlay 3x

    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 destruc-
           tive.

### copywin

           The copywin routine provides a finer granularity of  control  over  the
           overlay  and overwrite routines.  As in the prefresh routine, a rectan-
           gle 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  com-
           pletion.

           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 im-
           plementation).

## SEE ALSO

           curses(3x), curs_pad(3x), curs_refresh(3x)

                                                                  curs_overlay(3x)