def_prog_mode, def_shell_mode, reset_prog_mode,
reset_shell_mode, resetty, savetty, getsyx,
setsyx, ripoffline, curs_set, napms - low-level
void getsyx(int y, int x);
void setsyx(int y, int x);
int ripoffline(int line, int
(*init)(WINDOW *, int));
The following routines give low-level access to various curses
capabilities. These routines typically are used inside library routines.
The def_prog_mode and def_shell_mode routines save the current
terminal modes as the “program” (in curses) or
“shell” (not in curses) state for use by the
reset_prog_mode and reset_shell_mode routines. This is done
automatically by initscr. There is one such save area for each screen
context allocated by newterm.
The reset_prog_mode and reset_shell_mode routines restore the
terminal to “program” (in curses) or
“shell” (out of curses) state. These are done
automatically by endwin(3X) and, after an endwin, by
doupdate, so they normally are not called.
The resetty and savetty routines save and restore the state of the
terminal modes. savetty saves the current state in a buffer and
resetty restores the state to what it was at the last call to
The getsyx routine returns the current coordinates of the virtual
screen cursor in y and x. If leaveok is currently
TRUE, then -1,-1 is returned. If lines have been removed
from the top of the screen, using ripoffline, y and x
include these lines; therefore, y and x should be used only as
arguments for setsyx.
int curs_set(int visibility);
int napms(int ms);
Few applications will use this feature, most use getyx
The setsyx routine sets the virtual screen cursor to y,
x. If y and x are both -1, then leaveok is
set. The two routines getsyx and setsyx are designed to be used
by a library routine, which manipulates curses windows but does not
want to change the current position of the program's cursor. The library
routine would call getsyx at the beginning, do its manipulation of its
own windows, do a wnoutrefresh on its windows, call setsyx, and
then call doupdate.
Few applications will use this feature, most use wmove
The ripoffline routine provides access to the same facility that
slk_init [see curs_slk(3X)] uses to reduce the size of the
screen. ripoffline must be called before initscr or
newterm is called, to prepare these initial actions:
- If line is positive, a line is removed from the top of
- if line is negative, a line is removed from the bottom.
When the resulting initialization is done inside initscr,
the routine init (supplied by the user) is called with two
- a window pointer to the one-line window that has been allocated and
- an integer with the number of columns in the window.
Inside this initialization routine, the integer variables
LINES and COLS (defined in <curses.h>) are not
guaranteed to be accurate and wrefresh or doupdate must not be
called. It is allowable to call wnoutrefresh during the
ripoffline can be called up to five times before calling
initscr or newterm.
The curs_set routine sets the cursor state to invisible, normal, or very
visible for visibility equal to 0, 1, or 2
respectively. If the terminal supports the visibility requested, the
previous cursor state is returned; otherwise, ERR is returned.
The napms routine is used to sleep for ms milliseconds.
Except for curs_set, these routines always return OK.
curs_set returns the previous cursor state, or ERR
if the requested visibility is not supported.
X/Open defines no error conditions. In this implementation
Note that getsyx is a macro, so & is not necessary before the
variables y and x.
- def_prog_mode, def_shell_mode, reset_prog_mode,
- return an error if the terminal was not initialized, or if the I/O call to
obtain the terminal settings fails.
- returns an error if the maximum number of ripped-off lines exceeds the
maximum (NRIPS = 5).
Older SVr4 man pages warn that the return value of curs_set
“is currently incorrect”. This implementation gets it right,
but it may be unwise to count on the correctness of the return value
Both ncurses and SVr4 will call curs_set in endwin
if curs_set has been called to make the cursor other than normal,
i.e., either invisible or very visible. There is no way for ncurses to
determine the initial cursor state to restore that.
The virtual screen functions setsyx and getsyx are not
described in the XSI Curses standard, Issue 4. All other functions are as
described in XSI Curses.
The SVr4 documentation describes setsyx and getsyx
as having return type int. This is misleading, as they are macros with no
documented semantics for the return value.