CLEAROK(3XCURSES) X/Open Curses Library Functions CLEAROK(3XCURSES)

NAME

clearok, idlok, leaveok, scrollok, setscrreg, wsetscrreg - terminal
output control functions

SYNOPSIS

cc [ flag... ] file... -I /usr/xpg4/include -L /usr/xpg4/lib \
-R /usr/xpg4/lib -lcurses [ library... ]

c89 [ flag... ] file... -lcurses [ library... ]

#include <curses.h>

int clearok(WINDOW *win, bool bf);


int idlok(WINDOW *win, bool bf);


int leaveok(WINDOW *win, bool bf);


int scrollok(WINDOW *win, bool bf);


int setscrreg(int top, int bot);


int wsetscrreg(WINDOW *win, int top, int bot);

DESCRIPTION

These functions set options that deal with the output within Curses
functions.


The clearok() function assigns the value of bf to an internal flag in
the specified window that governs clearing of the screen during a
refresh. If, during a refresh operation on the specified window, the
flag in curscr is TRUE or the flag in the specified window is TRUE,
clearok() clears the screen, redraws it in its entirety, and sets the
flag to FALSE in curscr and in the specified window. The initial
state is unspecified


The idlok() function specifies whether the implementation may use the
hardware insert-line, delete-line, and scroll features of terminals
so equipped. If bf is TRUE, use of these features is enabled. If bf
is FALSE, use of these features is disabled and lines are instead
redrawn as required. The initial state is FALSE.


The leaveok() function controls the cursor position after a refresh
operation. If bf is TRUE, refresh operations on the specified window
may leave the terminal's cursor at an arbitrary position. If bf is
FALSE, then at the end of any refresh operation, the terminal's
cursor is positioned at the cursor position contained in the
specified window. The initial state is FALSE.


The scrollok() function controls the use of scrolling.If bf is TRUE,
then scrolling is enabled for the specified window. If bf is FALSE,
scrolling is disabled for the specified window. The initial state is
FALSE.


The setscrreg() and wsetscrreg() functions define a software
scrolling region in the current or specified window. The top and
bottom arguments are the line numbers of the first and last line
defining the scrolling region. (Line 0 is the top line of the
window.) If this option and scrollok() are enabled, an attempt to
move off the last line of the margin causes all lines in the
scrolling region to scroll one line in the direction of the first
line. Only characters in the window are scrolled. If a software
scrolling region is set and scrollok() is not enabled, an attempt to
move off the last line of the margin does not reposition any lines in
the scrolling region.

PARAMETERS

win
Is a pointer to a window.


bf
Is a Boolean expression.


top
Is the top line of the scrolling region (top of the window is
line 0).


bot
Is the bottom line of the scrolling region (top of the window
is line 0).

RETURN VALUES

Upon successful completion, the setscrreg() and wsetscrreg()
functions return OK. Otherwise, they return ERR.


The other functions always return OK.

ERRORS

No errors are defined.

USAGE

The only reason to enable the idlok() feature is to use scrolling to
achieve the visual effect of motion of a partial window, such as for
a screen editor. In other cases, the feature can be visually
annoying.


The leaveok() option provides greater efficiency for applications
that do not use the cursor.

ATTRIBUTES

See attributes(7) for descriptions of the following attributes:


+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Interface Stability | Standard |
+--------------------+-----------------+
|MT-Level | Unsafe |
+--------------------+-----------------+

SEE ALSO

bkgdset(3XCURSES), clear(3XCURSES), doupdate(3XCURSES),
libcurses(3XCURSES), scrl(3XCURSES), attributes(7), standards(7)

June 5, 2002 CLEAROK(3XCURSES)