- These routines set options that change the style of output within curs-
- es. All options are initially FALSE, unless otherwise stated. It is
- not necessary to turn these options off before calling endwin(3x).
+ These routines set options that change the style of output within
+ curses. All options are initially FALSE, unless otherwise stated. It
+ is not necessary to turn these options off before calling endwin(3x).
If idlok is called with TRUE as second argument, curses considers using
the hardware insert/delete line feature of terminals so equipped.
- Calling idlok with FALSE as second argument disables use of line inser-
- tion and deletion. This option should be enabled only if the applica-
- tion needs insert/delete line, for example, for a screen editor. It is
- disabled by default because insert/delete line tends to be visually an-
- noying when used in applications where it is not really needed. If in-
- sert/delete line cannot be used, curses redraws the changed portions of
- all lines.
+ Calling idlok with FALSE as second argument disables use of line
+ insertion and deletion. This option should be enabled only if the
+ application needs insert/delete line, for example, for a screen editor.
+ It is disabled by default because insert/delete line tends to be
+ visually annoying when used in applications where it is not really
+ needed. If insert/delete line cannot be used, curses redraws the
+ changed portions of all lines.
- If idcok is called with FALSE as second argument, curses no longer con-
- siders using the hardware insert/delete character feature of terminals
- so equipped. Use of character insert/delete is enabled by default.
- Calling idcok with TRUE as second argument re-enables use of character
- insertion and deletion.
+ If idcok is called with FALSE as second argument, curses no longer
+ considers using the hardware insert/delete character feature of
+ terminals so equipped. Use of character insert/delete is enabled by
+ default. Calling idcok with TRUE as second argument re-enables use of
+ character insertion and deletion.
If immedok is called with TRUEasargument, any change in the window
- image, such as the ones caused by waddch,wclrtobot,wscrl, etc., auto-
- matically cause a call to wrefresh. However, it may degrade perfor-
- mance considerably, due to repeated calls to wrefresh. It is disabled
- by default.
+ image, such as the ones caused by waddch,wclrtobot,wscrl, etc.,
+ automatically cause a call to wrefresh. However, it may degrade
+ performance considerably, due to repeated calls to wrefresh. It is
+ disabled by default.
Normally, the hardware cursor is left at the location of the window
cursor being refreshed. The leaveok option allows the cursor to be
- left wherever the update happens to leave it. It is useful for appli-
- cations where the cursor is not used, since it reduces the need for
- cursor motions.
+ left wherever the update happens to leave it. It is useful for
+ applications where the cursor is not used, since it reduces the need
+ for cursor motions.
The scrollok option controls what happens when the cursor of a window
is moved off the edge of the window or scrolling region, either as a
- result of a newline action on the bottom line, or typing the last char-
- acter of the last line. If disabled, (bf is FALSE), the cursor is left
- on the bottom line. If enabled, (bf is TRUE), the window is scrolled
- up one line (Note that to get the physical scrolling effect on the ter-
- minal, it is also necessary to call idlok).
+ result of a newline action on the bottom line, or typing the last
+ character of the last line. If disabled, (bf is FALSE), the cursor is
+ left on the bottom line. If enabled, (bf is TRUE), the window is
+ scrolled up one line (Note that to get the physical scrolling effect on
+ the terminal, it is also necessary to call idlok).
The setscrreg and wsetscrreg routines allow the application programmer
- to set a software scrolling region in a window. The top and bot param-
- eters are the line numbers of the top and bottom margin of the
- scrolling region. (Line 0 is the top line of the window.) If this op-
- tion and scrollok are enabled, an attempt to move off the bottom margin
- line causes all lines in the scrolling region to scroll one line in the
- direction of the first line. Only the text of the window is scrolled.
- (Note that this has nothing to do with the use of a physical scrolling
- region capability in the terminal, like that in the VT100. If idlok is
- enabled and the terminal has either a scrolling region or insert/delete
- line capability, they will probably be used by the output routines.)
+ to set a software scrolling region in a window. The top and bot
+ parameters are the line numbers of the top and bottom margin of 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 bottom
+ margin line causes all lines in the scrolling region to scroll one line
+ in the direction of the first line. Only the text of the window is
+ scrolled. (Note that this has nothing to do with the use of a physical
+ scrolling region capability in the terminal, like that in the VT100.
+ If idlok is enabled and the terminal has either a scrolling region or
+ insert/delete line capability, they will probably be used by the output
+ routines.)
- The functions setscrreg and wsetscrreg return OK upon success and ERR
- upon failure. All other routines that return an integer always return
+ The functions setscrreg and wsetscrreg return OK upon success and ERR
+ upon failure. All other routines that return an integer always return
OK.
X/Open Curses does not define any error conditions.
In this implementation,
- o those functions that have a window pointer will return an error if
+ o those functions that have a window pointer will return an error if
the window pointer is null
- owsetscrreg returns an error if the scrolling region limits extend
+ owsetscrreg returns an error if the scrolling region limits extend
outside the window.
- X/Open does not define any error conditions. This implementation re-
- turns an error if the window pointer is null.
+ X/Open does not define any error conditions. This implementation
+ returns an error if the window pointer is null.
These functions are described in the XSI Curses standard, Issue 4.
- From the outset, ncurses used nl/nonl to control the conversion of new-
- lines to carriage return/line-feed on output as well as input. XSI
- Curses documents only the use of these functions for input. This dif-
- ference arose from converting the pcurses source (which used ioctl
- calls with the sgttyb structure) to termios (i.e., the POSIX terminal
+ From the outset, ncurses used nl/nonl to control the conversion of
+ newlines to carriage return/line-feed on output as well as input. XSI
+ Curses documents only the use of these functions for input. This
+ difference arose from converting the pcurses source (which used ioctl
+ calls with the sgttyb structure) to termios (i.e., the POSIX terminal
interface). In the former, both input and output were controlled via a
- single option CRMOD, while the latter separates these features. Be-
- cause that conversion interferes with output optimization, nl/nonl were
- amended after ncurses 6.2 to eliminate their effect on output.
+ single option CRMOD, while the latter separates these features.
+ Because that conversion interferes with output optimization, nl/nonl
+ were amended after ncurses 6.2 to eliminate their effect on output.
- Some historic curses implementations had, as an undocumented feature,
- the ability to do the equivalent of clearok(...,1) by saying touch-
- win(stdscr) or clear(stdscr). This will not work under ncurses.
+ Some historic curses implementations had, as an undocumented feature,
+ the ability to do the equivalent of clearok(...,1) by saying
+ touchwin(stdscr) or clear(stdscr). This will not work under ncurses.
- Earlier System V curses implementations specified that with scrollok
- enabled, any window modification triggering a scroll also forced a
+ Earlier System V curses implementations specified that with scrollok
+ enabled, any window modification triggering a scroll also forced a
physical refresh. XSI Curses does not require this, and ncurses avoids
- doing it to perform better vertical-motion optimization at wrefresh
+ doing it to perform better vertical-motion optimization at wrefresh
time.
The XSI Curses standard does not mention that the cursor should be made
- invisible as a side-effect of leaveok. SVr4 curses documentation does
- this, but the code does not. Use curs_set to make the cursor invisi-
- ble.
+ invisible as a side-effect of leaveok. SVr4 curses documentation does
+ this, but the code does not. Use curs_set to make the cursor
+ invisible.
- Note that clearok, leaveok, scrollok, idcok, and setscrreg may be
+ Note that clearok, leaveok, scrollok, idcok, and setscrreg may be
macros.
- The immedok routine is useful for windows that are used as terminal em-
- ulators.
+ The immedok routine is useful for windows that are used as terminal
+ emulators.