curs_overlay(3X)                                            curs_overlay(3X)

NAME         top

       overlay, overwrite, copywin - overlay and manipulate overlapped
       curses windows

SYNOPSIS         top

       #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         top

   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.

       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         top

       Routines that return an integer return ERR upon failure, and OK (SVr4
       only specifies "an integer value other than ERR") upon successful

       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-

NOTES         top

       Note that overlay and overwrite may be macros.

PORTABILITY         top

       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         top

       curses(3X), curs_pad(3X), curs_refresh(3X)

COLOPHON         top

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