curs_touch 3x

curs_touch(3x)                                           curs_touch(3x)

NAME

       touchwin, touchline, untouchwin, wtouchln, is_linetouched,
       is_wintouched - curses refresh control routines

SYNOPSIS

       #include <curses.h>
       int touchwin(WINDOW *win);
       int touchline(WINDOW *win, int start, int count);
       int untouchwin(WINDOW *win);
       int wtouchln(WINDOW *win, int y, int n, int changed);
       bool is_linetouched(WINDOW *win, int line);
       bool is_wintouched(WINDOW *win);

DESCRIPTION

       The touchwin and touchline routines throw away  all  opti-
       mization  information about which parts of the window have
       been touched, by pretending that  the  entire  window  has
       been  drawn  on.   This  is sometimes necessary when using
       overlapping windows, since a change to one window  affects
       the other window, but the records of which lines have been
       changed in the other window do  not  reflect  the  change.
       The  routine touchline only pretends that count lines have
       been changed, beginning with line start.

       The untouchwin routine marks all lines in  the  window  as
       unchanged since the last call to wrefresh.

       The wtouchln routine makes n lines in the window, starting
       at line y, look as if they have (changed=1)  or  have  not
       (changed=0) been changed since the last call to wrefresh.

       The  is_linetouched and is_wintouched routines return TRUE
       if the specified line/window was modified since  the  last
       call  to  wrefresh; otherwise they return FALSE.  In addi-
       tion, is_linetouched returns ERR if line is not valid  for
       the given window.

RETURN VALUE

       All  routines  return  the integer ERR upon failure and an
       integer value other than ERR upon  successful  completion,
       unless  otherwise  noted in the preceding routine descrip-
       tions.

       X/Open does not define any error conditions.  In this  im-
       plementation

              is_linetouched
                   returns  an  error  if  the  window pointer is
                   null, or if the line  number  is  outside  the
                   window.   Note  that ERR is distinct from TRUE
                   and FALSE, which are the normal return  values
                   of this function.

              wtouchln
                   returns  an  error  if  the  window pointer is
                   null, or if the line  number  is  outside  the
                   window.

PORTABILITY

       The  XSI  Curses  standard,  Issue 4 describes these func-
       tions.

       Some historic curses implementations had,  as  an  undocu-
       mented  feature,  the  ability  to  do  the  equivalent of
       clearok(..., 1) by saying touchwin(stdscr)  or  clear(std-
       scr).  This will not work under ncurses.

NOTES

       Note that all routines except wtouchln may be macros.

SEE ALSO

       curses(3x), curs_refresh(3x), curs_variables(3x).



                                                         curs_touch(3x)