+
#include <curses.h>
-DESCRIPTION
+
The ncurses library routines give the user a terminal-
- independent method of updating character screens with
- reasonable optimization. This implementation is ``new
- curses'' (ncurses) and is the approved replacement for
- 4.4BSD classic curses, which has been discontinued.
-
- The ncurses routines emulate the curses(3x) library of
- System V Release 4 UNIX, and the XPG4 curses standard (XSI
- curses) but the ncurses library is freely redistributable
- in source form. Differences from the SVr4 curses are
- summarized under the EXTENSIONS and BUGS sections below
- and described in detail in the EXTENSIONS and BUGS
- sections of individual man pages.
+ independent method of updating character screens with rea-
+ sonable optimization. This implementation is "new curses"
+ (ncurses) and is the approved replacement for 4.4BSD clas-
+ sic curses, which has been discontinued. This describes
+ ncurses version 6.0 (patch 20151024).
+
+ The ncurses library emulates the curses library of System
+ V Release 4 UNIX, and XPG4 (X/Open Portability Guide)
+ curses (also known as XSI curses). XSI stands for X/Open
+ System Interfaces Extension. The ncurses library is
+ freely redistributable in source form. Differences from
+ the SVr4 curses are summarized under the EXTENSIONS and
+ PORTABILITY sections below and described in detail in the
+ respective EXTENSIONS, PORTABILITY and BUGS sections of
+ individual man pages.
+
+ The ncurses library also provides many useful extensions,
+ i.e., features which cannot be implemented by a simple
+ add-on library but which require access to the internals
+ of the library.
A program using these routines must be linked with the
-lncurses option, or (if it has been generated) with the
debugging library -lncurses_g. (Your system integrator
may also have installed these libraries under the names
-lcurses and -lcurses_g.) The ncurses_g library generates
- trace logs (in a file called 'trace' in the current
- directory) that describe curses actions.
-
- The ncurses package supports: overall screen, window and
- pad manipulation; output to windows and pads; reading
- terminal input; control over terminal and curses input and
- output options; environment query routines; color
- manipulation; use of soft label keys; terminfo
- capabilities; and access to low-level terminal-
- manipulation routines.
-
- To initialize the routines, the routine initscr or newterm
- must be called before any of the other routines that deal
- with windows and screens are used. The routine endwin
- must be called before exiting. To get character-at-a-time
- input without echoing (most interactive, screen oriented
- programs want this), the following sequence should be
- used:
+ trace logs (in a file called 'trace' in the current direc-
+ tory) that describe curses actions. See also the section
+ on ALTERNATE CONFIGURATIONS.
+
+ The ncurses package supports: overall screen, window and
+ pad manipulation; output to windows and pads; reading ter-
+ minal input; control over terminal and curses input and
+ output options; environment query routines; color manipu-
+ lation; use of soft label keys; terminfo capabilities; and
+ access to low-level terminal-manipulation routines.
+
+
+
+
+ The library uses the locale which the calling program has
+ initialized. That is normally done with setlocale:
+
+ setlocale(LC_ALL, "");
+
+ If the locale is not initialized, the library assumes that
+ characters are printable as in ISO-8859-1, to work with
+ certain legacy programs. You should initialize the locale
+ and not rely on specific details of the library when the
+ locale has not been setup.
+
+ The function initscr or newterm must be called to initial-
+ ize the library before any of the other routines that deal
+ with windows and screens are used. The routine endwin
+ must be called before exiting.
+
+ To get character-at-a-time input without echoing (most
+ interactive, screen oriented programs want this), the fol-
+ lowing sequence should be used:
initscr(); cbreak(); noecho();
@@ -100,74 +127,80 @@
intrflush(stdscr, FALSE);
keypad(stdscr, TRUE);
- Before a curses program is run, the tab stops of the
- terminal should be set and its initialization strings, if
+ Before a curses program is run, the tab stops of the ter-
+ minal should be set and its initialization strings, if
defined, must be output. This can be done by executing
the tput init command after the shell environment variable
TERM has been exported. tset(1) is usually responsible
for doing this. [See terminfo(5) for further details.]
- The ncurses library permits manipulation of data
- structures, called windows, which can be thought of as
- two-dimensional arrays of characters representing all or
- part of a CRT screen. A default window called stdscr,
- which is the size of the terminal screen, is supplied.
- Others may be created with newwin.
+
+
+
+ The ncurses library permits manipulation of data struc-
+ tures, called windows, which can be thought of as two-
+ dimensional arrays of characters representing all or part
+ of a CRT screen. A default window called stdscr, which is
+ the size of the terminal screen, is supplied. Others may
+ be created with newwin.
Note that curses does not handle overlapping windows,
- that's done by the panel(3x) library. This means that you
- can either use stdscr or divide the screen into tiled
- windows and not using stdscr at all. Mixing the two will
+ that's done by the panel(3x) library. This means that you
+ can either use stdscr or divide the screen into tiled win-
+ dows and not using stdscr at all. Mixing the two will
result in unpredictable, and undesired, effects.
Windows are referred to by variables declared as WINDOW *.
These data structures are manipulated with routines
described here and elsewhere in the ncurses manual pages.
- Among which the most basic routines are move and addch.
+ Among those, the most basic routines are move and addch.
More general versions of these routines are included with
names beginning with w, allowing the user to specify a
- window. The routines not beginning with w affect stdscr.)
+ window. The routines not beginning with w affect stdscr.
- After using routines to manipulate a window, refresh is
- called, telling curses to make the user's CRT screen look
- like stdscr. The characters in a window are actually of
- type chtype, (character and attribute data) so that other
- information about the character may also be stored with
+ After using routines to manipulate a window, refresh is
+ called, telling curses to make the user's CRT screen look
+ like stdscr. The characters in a window are actually of
+ type chtype, (character and attribute data) so that other
+ information about the character may also be stored with
each character.
- Special windows called pads may also be manipulated.
+ Special windows called pads may also be manipulated.
These are windows which are not constrained to the size of
- the screen and whose contents need not be completely
- displayed. See curs_pad(3x) for more information.
-
- In addition to drawing characters on the screen, video
- attributes and colors may be supported, causing the
- characters to show up in such modes as underlined, in
- reverse video, or in color on terminals that support such
- display enhancements. Line drawing characters may be
- specified to be output. On input, curses is also able to
- translate arrow and function keys that transmit escape
- sequences into single values. The video attributes, line
- drawing characters, and input values use names, defined in
+ the screen and whose contents need not be completely dis-
+ played. See curs_pad(3x) for more information.
+
+ In addition to drawing characters on the screen, video
+ attributes and colors may be supported, causing the char-
+ acters to show up in such modes as underlined, in reverse
+ video, or in color on terminals that support such display
+ enhancements. Line drawing characters may be specified to
+ be output. On input, curses is also able to translate
+ arrow and function keys that transmit escape sequences
+ into single values. The video attributes, line drawing
+ characters, and input values use names, defined in
<curses.h>, such as A_REVERSE, ACS_HLINE, and KEY_LEFT.
+
+
+
If the environment variables LINES and COLUMNS are set, or
- if the program is executing in a window environment, line
- and column information in the environment will override
- information read by terminfo. This would effect a program
- running in an AT&T 630 layer, for example, where the size
+ if the program is executing in a window environment, line
+ and column information in the environment will override
+ information read by terminfo. This would affect a program
+ running in an AT&T 630 layer, for example, where the size
of a screen is changeable (see ENVIRONMENT).
- If the environment variable TERMINFO is defined, any
- program using curses checks for a local terminal
- definition before checking in the standard place. For
- example, if TERM is set to att4424, then the compiled
- terminal definition is found in
+ If the environment variable TERMINFO is defined, any pro-
+ gram using curses checks for a local terminal definition
+ before checking in the standard place. For example, if
+ TERM is set to att4424, then the compiled terminal defini-
+ tion is found in
/usr/share/terminfo/a/att4424.
(The a is copied from the first letter of att4424 to avoid
- creation of huge directories.) However, if TERMINFO is
+ creation of huge directories.) However, if TERMINFO is
set to $HOME/myterms, curses first checks
$HOME/myterms/a/att4424,
@@ -176,51 +209,105 @@
/usr/share/terminfo/a/att4424.
- This is useful for developing experimental definitions or
- when write permission in /usr/share/terminfo is not
- available.
+ This is useful for developing experimental definitions or
+ when write permission in /usr/share/terminfo is not avail-
+ able.
- The integer variables LINES and COLS are defined in
- <curses.h> and will be filled in by initscr with the size
- of the screen. The constants TRUE and FALSE have the
- values 1 and 0, respectively.
+ The integer variables LINES and COLS are defined in
+ <curses.h> and will be filled in by initscr with the size
+ of the screen. The constants TRUE and FALSE have the val-
+ ues 1 and 0, respectively.
- The curses routines also define the WINDOW * variable
+ The curses routines also define the WINDOW * variable
curscr which is used for certain low-level operations like
- clearing and redrawing a screen containing garbage. The
+ clearing and redrawing a screen containing garbage. The
curscr can be used in only a few routines.
- Routine and Argument Names
- Many curses routines have two or more versions. The
- routines prefixed with w require a window argument. The
- routines prefixed with p require a pad argument. Those
- without a prefix generally use stdscr.
+
+
+ Many curses routines have two or more versions. The rou-
+ tines prefixed with w require a window argument. The rou-
+ tines prefixed with p require a pad argument. Those with-
+ out a prefix generally use stdscr.
The routines prefixed with mv require a y and x coordinate
- to move to before performing the appropriate action. The
- mv routines imply a call to move before the call to the
- other routine. The coordinate y always refers to the row
- (of the window), and x always refers to the column. The
+ to move to before performing the appropriate action. The
+ mv routines imply a call to move before the call to the
+ other routine. The coordinate y always refers to the row
+ (of the window), and x always refers to the column. The
upper left-hand corner is always (0,0), not (1,1).
The routines prefixed with mvw take both a window argument
- and x and y coordinates. The window argument is always
+ and x and y coordinates. The window argument is always
specified before the coordinates.
- In each case, win is the window affected, and pad is the
- pad affected; win and pad are always pointers to type
- WINDOW.
+ In each case, win is the window affected, and pad is the
+ pad affected; win and pad are always pointers to type WIN-
+ DOW.
Option setting routines require a Boolean flag bf with the
- value TRUE or FALSE; bf is always of type bool. The
- variables ch and attrs below are always of type chtype.
- The types WINDOW, SCREEN, bool, and chtype are defined in
- <curses.h>. The type TERMINAL is defined in <term.h>.
- All other arguments are integers.
+ value TRUE or FALSE; bf is always of type bool. Most of
+ the data types used in the library routines, such as WIN-
+ DOW, SCREEN, bool, and chtype are defined in <curses.h>.
+ Types used for the terminfo routines such as TERMINAL are
+ defined in <term.h>.
+
+ This manual page describes functions which may appear in
+ any configuration of the library. There are two common
+ configurations of the library:
+
+ ncurses
+ the "normal" library, which handles 8-bit charac-
+ ters. The normal (8-bit) library stores charac-
+ ters combined with attributes in chtype data.
+
+ Attributes alone (no corresponding character) may
+ be stored in chtype or the equivalent attr_t data.
+ In either case, the data is stored in something
+ like an integer.
+
+ Each cell (row and column) in a WINDOW is stored
+ as a chtype.
+
+ ncursesw
+ the so-called "wide" library, which handles multi-
+ byte characters (see the section on ALTERNATE CON-
+ FIGURATIONS). The "wide" library includes all of
+ the calls from the "normal" library. It adds
+ about one third more calls using data types which
+ store multibyte characters:
+
+ cchar_t
+ corresponds to chtype. However it is a
+ structure, because more data is stored than
+ can fit into an integer. The characters are
+ large enough to require a full integer value
+ - and there may be more than one character
+ per cell. The video attributes and color are
+ stored in separate fields of the structure.
+
+ Each cell (row and column) in a WINDOW is
+ stored as a cchar_t.
+
+ wchar_t
+ stores a "wide" character. Like chtype, this
+ may be an integer.
+
+ wint_t
+ stores a wchar_t or WEOF - not the same,
+ though both may have the same size.
+
+ The "wide" library provides new functions which
+ are analogous to functions in the "normal"
+ library. There is a naming convention which
+ relates many of the normal/wide variants: a "_w"
+ is inserted into the name. For example, waddch
+ becomes wadd_wch.
- Routine Name Index
+
+
The following table lists each curses routine and the name
of the manual page on which it is described. Routines
flagged with `*' are ncurses-specific, not described by
@@ -230,10 +317,13 @@
--------------------------------------------
COLOR_PAIR curs_color(3x)
PAIR_NUMBER curs_attr(3x)
+ _nc_free_and_exit curs_memleaks(3x)*
+ _nc_freeall curs_memleaks(3x)*
_nc_tracebits curs_trace(3x)*
_traceattr curs_trace(3x)*
_traceattr2 curs_trace(3x)*
_tracechar curs_trace(3x)*
+
_tracechtype curs_trace(3x)*
_tracechtype2 curs_trace(3x)*
_tracedump curs_trace(3x)*
@@ -262,7 +352,6 @@
bkgd curs_bkgd(3x)
bkgdset curs_bkgd(3x)
bkgrnd curs_bkgrnd(3x)
-
bkgrndset curs_bkgrnd(3x)
border curs_border(3x)
border_set curs_border_set(3x)
@@ -301,22 +390,31 @@
erasewchar curs_termattrs(3x)
filter curs_util(3x)
flash curs_beep(3x)
+
flushinp curs_util(3x)
get_wch curs_get_wch(3x)
get_wstr curs_get_wstr(3x)
+ getattrs curs_attr(3x)
+ getbegx curs_legacy(3x)*
+ getbegy curs_legacy(3x)*
getbegyx curs_getyx(3x)
getbkgd curs_bkgd(3x)
getbkgrnd curs_bkgrnd(3x)
getcchar curs_getcchar(3x)
getch curs_getch(3x)
+ getcurx curs_legacy(3x)*
+ getcury curs_legacy(3x)*
+ getmaxx curs_legacy(3x)*
+ getmaxy curs_legacy(3x)*
getmaxyx curs_getyx(3x)
getmouse curs_mouse(3x)*
getn_wstr curs_get_wstr(3x)
getnstr curs_getstr(3x)
+ getparx curs_legacy(3x)*
+ getpary curs_legacy(3x)*
getparyx curs_getyx(3x)
getstr curs_getstr(3x)
getsyx curs_kernel(3x)
-
getwin curs_util(3x)
getyx curs_getyx(3x)
halfdelay curs_inopts(3x)
@@ -351,9 +449,24 @@
instr curs_instr(3x)
intrflush curs_inopts(3x)
inwstr curs_inwstr(3x)
+ is_cleared curs_opaque(3x)*
+ is_idcok curs_opaque(3x)*
+ is_idlok curs_opaque(3x)*
+ is_immedok curs_opaque(3x)*
+ is_keypad curs_opaque(3x)*
+ is_leaveok curs_opaque(3x)*
is_linetouched curs_touch(3x)
+ is_nodelay curs_opaque(3x)*
+
+ is_notimeout curs_opaque(3x)*
+ is_pad curs_opaque(3x)*
+ is_scrollok curs_opaque(3x)*
+ is_subwin curs_opaque(3x)*
+ is_syncok curs_opaque(3x)*
+ is_term_resized resizeterm(3x)*
is_wintouched curs_touch(3x)
isendwin curs_initscr(3x)
+ key_defined key_defined(3x)*
key_name curs_util(3x)
keybound keybound(3x)*
keyname curs_util(3x)
@@ -370,7 +483,6 @@
mousemask curs_mouse(3x)*
move curs_move(3x)
mvadd_wch curs_add_wch(3x)
-
mvadd_wchnstr curs_add_wchstr(3x)
mvadd_wchstr curs_add_wchstr(3x)
mvaddch curs_addch(3x)
@@ -412,6 +524,7 @@
mvscanw curs_scanw(3x)
mvvline curs_border(3x)
mvvline_set curs_border_set(3x)
+
mvwadd_wch curs_add_wch(3x)
mvwadd_wchnstr curs_add_wchstr(3x)
mvwadd_wchstr curs_add_wchstr(3x)
@@ -424,7 +537,6 @@
mvwaddwstr curs_addwstr(3x)
mvwchgat curs_attr(3x)
mvwdelch curs_delch(3x)
-
mvwget_wch curs_get_wch(3x)
mvwget_wstr curs_get_wstr(3x)
mvwgetch curs_getch(3x)
@@ -462,6 +574,7 @@
nocbreak curs_inopts(3x)
nodelay curs_inopts(3x)
noecho curs_inopts(3x)
+ nofilter curs_util(3x)*
nonl curs_outopts(3x)
noqiflush curs_inopts(3x)
noraw curs_inopts(3x)
@@ -483,6 +596,7 @@
reset_prog_mode curs_kernel(3x)
reset_shell_mode curs_kernel(3x)
resetty curs_kernel(3x)
+ resize_term resizeterm(3x)*
resizeterm resizeterm(3x)*
restartterm curs_terminfo(3x)
ripoffline curs_kernel(3x)
@@ -532,10 +646,10 @@
tgetnum curs_termcap(3x)
tgetstr curs_termcap(3x)
tgoto curs_termcap(3x)
-
tigetflag curs_terminfo(3x)
tigetnum curs_terminfo(3x)
tigetstr curs_terminfo(3x)
+ tiparm curs_terminfo(3x)*
timeout curs_inopts(3x)
touchline curs_touch(3x)
touchwin curs_touch(3x)
@@ -544,6 +658,7 @@
tputs curs_terminfo(3x)
trace curs_trace(3x)*
typeahead curs_inopts(3x)
+
unctrl curs_util(3x)
unget_wch curs_get_wch(3x)
ungetch curs_getch(3x)
@@ -552,6 +667,8 @@
use_default_colors default_colors(3x)*
use_env curs_util(3x)
use_extended_names curs_extend(3x)*
+ use_legacy_coding legacy_coding(3x)*
+ use_tioctl curs_util(3x)
vid_attr curs_terminfo(3x)
vid_puts curs_terminfo(3x)
vidattr curs_terminfo(3x)
@@ -586,7 +703,6 @@
wborder curs_border(3x)
wborder_set curs_border_set(3x)
wchgat curs_attr(3x)
-
wclear curs_clear(3x)
wclrtobot curs_clear(3x)
wclrtoeol curs_clear(3x)
@@ -602,10 +718,14 @@
wget_wstr curs_get_wstr(3x)
wgetbkgrnd curs_bkgrnd(3x)
wgetch curs_getch(3x)
+ wgetdelay curs_opaque(3x)*
wgetn_wstr curs_get_wstr(3x)
wgetnstr curs_getstr(3x)
+ wgetparent curs_opaque(3x)*
+ wgetscrreg curs_opaque(3x)*
wgetstr curs_getstr(3x)
whline curs_border(3x)
+
whline_set curs_border_set(3x)
win_wch curs_in_wch(3x)
win_wchnstr curs_in_wchstr(3x)
@@ -640,7 +760,6 @@
wsyncdown curs_window(3x)
wsyncup curs_window(3x)
wtimeout curs_inopts(3x)
-
wtouchln curs_touch(3x)
wunctrl curs_util(3x)
wvline curs_border(3x)
@@ -648,399 +767,678 @@
-RETURN VALUE
+
Routines that return an integer return ERR upon failure
- and an integer value other than ERR upon successful
- completion, unless otherwise noted in the routine
- descriptions.
-
- All macros return the value of the w version, except
- setscrreg, wsetscrreg, getyx, getbegyx, getmaxyx. The
- return values of setscrreg, wsetscrreg, getyx, getbegyx,
- and getmaxyx are undefined (i.e., these should not be used
+ and an integer value other than ERR upon successful com-
+ pletion, unless otherwise noted in the routine descrip-
+ tions.
+
+ As a general rule, routines check for null pointers passed
+ as parameters, and handle this as an error.
+
+ All macros return the value of the w version, except
+ setscrreg, wsetscrreg, getyx, getbegyx, and getmaxyx. The
+ return values of setscrreg, wsetscrreg, getyx, getbegyx,
+ and getmaxyx are undefined (i.e., these should not be used
as the right-hand side of assignment statements).
Routines that return pointers return NULL on error.
-ENVIRONMENT
- The following environment symbols are useful for
- customizing the runtime behavior of the ncurses library.
- The most important ones have been already discussed in
- detail.
-
- BAUDRATE
- The debugging library checks this environment symbol
- when the application has redirected output to a file.
- The symbol's numeric value is used for the baudrate.
- If no value is found ncurses uses 9600. This allows
- testers to construct repeatable test-cases that take
- into account costs that depend on baudrate.
-
- CC When set, change occurrences of the command_character
- (i.e., the cmdch capability) of the loaded terminfo
- entries to the value of this symbol. Very few
- terminfo entries provide this feature.
-
- COLUMNS
- Specify the width of the screen in characters.
- Applications running in a windowing environment
- usually are able to obtain the width of the window in
- which they are executing. If neither the $COLUMNS
- value nor the terminal's screen size is available,
- ncurses uses the size which may be specified in the
- terminfo database (i.e., the cols capability).
-
- It is important that your application use a correct
- size for the screen. However, this is not always
- possible because your application may be running on a
- host which does not honor NAWS (Negotiations About
- Window Size), or because you are temporarily running
- as another user.
-
- Either COLUMNS or LINES symbols may be specified
- independently. This is mainly useful to circumvent
- legacy misfeatures of terminal descriptions, e.g.,
- xterm which commonly specifies a 65 line screen. For
- best results, lines and cols should not be specified
- in a terminal description for terminals which are run
- as emulations.
-
- Use the use_env function to disable this feature.
-
- ESCDELAY
- Specifies the total time, in milliseconds, for which
- ncurses will await a character sequence, e.g., a
- function key. The default value, 1000 milliseconds,
- is enough for most uses. However, it is made a
- variable to accommodate unusual applications.
-
- The most common instance where you may wish to change
- this value is to work with slow hosts, e.g., running
- on a network. If the host cannot read characters
- rapidly enough, it will have the same effect as if
- the terminal did not send characters rapidly enough.
- The library will still see a timeout.
-
- Note that xterm mouse events are built up from
- character sequences received from the xterm. If your
- application makes heavy use of multiple-clicking, you
- may wish to lengthen this default value because the
- timeout applies to the composed multi-click event as
- well as the individual clicks.
-
- HOME Tells ncurses where your home directory is. That is
- where it may read and write auxiliary terminal
- descriptions:
-
- $HOME/.termcap
- $HOME/.terminfo
-
- LINES
- Like COLUMNS, specify the height of the screen in
- characters. See COLUMNS for a detailed description.
-
- MOUSE_BUTTONS_123
- This applies only to the OS/2 EMX port. It specifies
- the order of buttons on the mouse. OS/2 numbers a
- 3-button mouse inconsistently from other platforms:
-
- 1 = left
- 2 = right
- 3 = middle.
-
- This symbol lets you customize the mouse. The symbol
- must be three numeric digits 1-3 in any order, e.g.,
- 123 or 321. If it is not specified, ncurses uses
- 132.
-
- NCURSES_ASSUMED_COLORS
- Override the compiled-in assumption that the
- terminal's default colors are white-on-black (see
- assume_default_colors(3x)). You may set the
- foreground and background color values with this
- environment variable by proving a 2-element list:
- foreground,background. For example, to tell ncurses
- to not assume anything about the colors, set this to
- "-1,-1". To make it green-on-black, set it to "2,0".
- Any positive value from zero to the terminfo
- max_colors value is allowed.
-
- NCURSES_NO_PADDING
- Most of the terminal descriptions in the terminfo
- database are written for real "hardware" terminals.
- Many people use terminal emulators which run in a
- windowing environment and use curses-based
- applications. Terminal emulators can duplicate all
- of the important aspects of a hardware terminal, but
- they do not have the same limitations. The chief
- limitation of a hardware terminal from the standpoint
- of your application is the management of dataflow,
- i.e., timing. Unless a hardware terminal is
- interfaced into a terminal concentrator (which does
- flow control), it (or your application) must manage
- dataflow, preventing overruns. The cheapest solution
- (no hardware cost) is for your program to do this by
- pausing after operations that the terminal does
- slowly, such as clearing the display.
-
- As a result, many terminal descriptions (including
- the vt100) have delay times embedded. You may wish
- to use these descriptions, but not want to pay the
- performance penalty.
-
- Set the NCURSES_NO_PADDING symbol to disable all but
- mandatory padding. Mandatory padding is used as a
- part of special control sequences such as flash.
-
- NCURSES_NO_SETBUF
- Normally ncurses enables buffered output during
- terminal initialization. This is done (as in SVr4
- curses) for performance reasons. For testing
- purposes, both of ncurses and certain applications,
- this feature is made optional. Setting the
- NCURSES_NO_SETBUF variable disables output buffering,
- leaving the output in the original (usually line
- buffered) mode.
-
- NCURSES_TRACE
- During initialization, the ncurses debugging library
- checks the NCURSES_TRACE symbol. If it is defined,
- to a numeric value, ncurses calls the trace function,
- using that value as the argument.
-
- The argument values, which are defined in curses.h,
- provide several types of information. When running
- with traces enabled, your application will write the
- file trace to the current directory.
-
- TERM Denotes your terminal type. Each terminal type is
- distinct, though many are similar.
-
- TERMCAP
- If the ncurses library has been configured with
- termcap support, ncurses will check for a terminal's
- description in termcap form if it is not available in
- the terminfo database.
-
- The TERMCAP symbol contains either a terminal
- description (with newlines stripped out), or a file
- name telling where the information denoted by the
- TERM symbol exists. In either case, setting it
- directs ncurses to ignore the usual place for this
- information, e.g., /etc/termcap.
-
- TERMINFO
- Overrides the directory in which ncurses searches for
- your terminal description. This is the simplest, but
- not the only way to change the list of directories.
- The complete list of directories in order follows:
-
- - the last directory to which ncurses wrote, if any,
- is searched first.
-
- - the directory specified by the TERMINFO symbol
-
- - $HOME/.terminfo
-
- - directories listed in the TERMINFO_DIRS symbol
-
- - one or more directories whose names are configured
- and compiled into the ncurses library, e.g.,
- /usr/share/terminfo
-
- TERMINFO_DIRS
- Specifies a list of directories to search for
- terminal descriptions. The list is separated by
- colons (i.e., ":") on Unix, semicolons on OS/2 EMX.
- All of the terminal descriptions are in terminfo
- form, which makes a subdirectory named for the first
- letter of the terminal names therein.
-
- TERMPATH
- If TERMCAP does not hold a file name then ncurses
- checks the TERMPATH symbol. This is a list of
- filenames separated by spaces or colons (i.e., ":")
- on Unix, semicolons on OS/2 EMX. If the TERMPATH
- symbol is not set, ncurses looks in the files
- /etc/termcap, /usr/share/misc/termcap and
- $HOME/.termcap, in that order.
-
- The library may be configured to disregard the following
- variables when the current user is the superuser (root),
- or if the application uses setuid or setgid permissions:
- $TERMINFO, $TERMINFO_DIRS, $TERMPATH, as well as $HOME.
+
+ The following environment symbols are useful for customiz-
+ ing the runtime behavior of the ncurses library. The most
+ important ones have been already discussed in detail.
+
+ CC
+ When set, change occurrences of the command_character
+ (i.e., the cmdch capability) of the loaded terminfo
+ entries to the value of this variable. Very few terminfo
+ entries provide this feature.
+
+ Because this name is also used in development environments
+ to represent the C compiler's name, ncurses ignores it if
+ it does not happen to be a single character.
-FILES
- /usr/share/tabset
- directory containing initialization files for the
- terminal capability database /usr/share/terminfo
- terminal capability database
+
+ The debugging library checks this environment variable
+ when the application has redirected output to a file. The
+ variable's numeric value is used for the baudrate. If no
+ value is found, ncurses uses 9600. This allows testers to
+ construct repeatable test-cases that take into account
+ costs that depend on baudrate.
-SEE ALSO
- terminfo(5) and related pages whose names begin "curs_"
- for detailed routine descriptions.
+
+ Specify the width of the screen in characters. Applica-
+ tions running in a windowing environment usually are able
+ to obtain the width of the window in which they are exe-
+ cuting. If neither the COLUMNS value nor the terminal's
+ screen size is available, ncurses uses the size which may
+ be specified in the terminfo database (i.e., the cols
+ capability).
+
+ It is important that your application use a correct size
+ for the screen. This is not always possible because your
+ application may be running on a host which does not honor
+ NAWS (Negotiations About Window Size), or because you are
+ temporarily running as another user. However, setting
+ COLUMNS and/or LINES overrides the library's use of the
+ screen size obtained from the operating system.
+
+ Either COLUMNS or LINES symbols may be specified indepen-
+ dently. This is mainly useful to circumvent legacy mis-
+ features of terminal descriptions, e.g., xterm which com-
+ monly specifies a 65 line screen. For best results, lines
+ and cols should not be specified in a terminal description
+ for terminals which are run as emulations.
+
+ Use the use_env function to disable all use of external
+ environment (but not including system calls) to determine
+ the screen size. Use the use_tioctl function to update
+ COLUMNS or LINES to match the screen size obtained from
+ system calls or the terminal database.
-EXTENSIONS
- The ncurses library can be compiled with an option
- (-DUSE_GETCAP) that falls back to the old-style
- /etc/termcap file if the terminal setup code cannot find a
- terminfo entry corresponding to TERM. Use of this feature
- is not recommended, as it essentially includes an entire
- termcap compiler in the ncurses startup code, at
- significant cost in core and startup cycles.
+
+ Specifies the total time, in milliseconds, for which
+ ncurses will await a character sequence, e.g., a function
+ key. The default value, 1000 milliseconds, is enough for
+ most uses. However, it is made a variable to accommodate
+ unusual applications.
+
+ The most common instance where you may wish to change this
+ value is to work with slow hosts, e.g., running on a net-
+ work. If the host cannot read characters rapidly enough,
+ it will have the same effect as if the terminal did not
+ send characters rapidly enough. The library will still
+ see a timeout.
+
+ Note that xterm mouse events are built up from character
+ sequences received from the xterm. If your application
+ makes heavy use of multiple-clicking, you may wish to
+ lengthen this default value because the timeout applies to
+ the composed multi-click event as well as the individual
+ clicks.
+
+ In addition to the environment variable, this implementa-
+ tion provides a global variable with the same name. Por-
+ table applications should not rely upon the presence of
+ ESCDELAY in either form, but setting the environment vari-
+ able rather than the global variable does not create prob-
+ lems when compiling an application.
- The ncurses library includes facilities for capturing
- mouse events on certain terminals (including xterm). See
- the curs_mouse(3x) manual page for details.
- The ncurses library includes facilities for responding to
- window resizing events, e.g., when running in an xterm.
- See the resizeterm(3x) and wresize(3x) manual pages for
- details. In addition, the library may be configured with
- a SIGWINCH handler.
+
+
+ Tells ncurses where your home directory is. That is where
+ it may read and write auxiliary terminal descriptions:
- The ncurses library extends the fixed set of function key
- capabilities of terminals by allowing the application
- designer to define additional key sequences at runtime.
- See the define_key(3x) and keyok(3x) manual pages for
- details.
-
- The ncurses library can exploit the capabilities of
- terminals which implement the ISO-6429 SGR 39 and SGR 49
- controls, which allow an application to reset the terminal
- to its original foreground and background colors. From
- the users' perspective, the application is able to draw
- colored text on a background whose color is set
- independently, providing better control over color
- contrasts. See the default_colors(3x) manual page for
- details.
-
- The ncurses library includes a function for directing
- application output to a printer attached to the terminal
- device. See the curs_print(3x) manual page for details.
+ $HOME/.termcap
+ $HOME/.terminfo
-PORTABILITY
- The ncurses library is intended to be BASE-level
- conformant with the XSI Curses standard. Certain portions
- of the EXTENDED XSI Curses functionality (including color
- support) are supported. The following EXTENDED XSI Curses
- calls in support of wide (multibyte) characters are not
- yet implemented: pecho_wchar, slk_wset.
+
+ Like COLUMNS, specify the height of the screen in charac-
+ ters. See COLUMNS for a detailed description.
- A small number of local differences (that is, individual
- differences between the XSI Curses and ncurses calls) are
- described in PORTABILITY sections of the library man
- pages.
- The routine has_key is not part of XPG4, nor is it present
- in SVr4. See the curs_getch(3x) manual page for details.
+
+
+ This applies only to the OS/2 EMX port. It specifies the
+ order of buttons on the mouse. OS/2 numbers a 3-button
+ mouse inconsistently from other platforms:
+
+ 1 = left
+ 2 = right
+ 3 = middle.
- The routine slk_attr is not part of XPG4, nor is it
- present in SVr4. See the curs_slk(3x) manual page for
- details.
+ This variable lets you customize the mouse. The variable
+ must be three numeric digits 1-3 in any order, e.g., 123
+ or 321. If it is not specified, ncurses uses 132.
- The routines getmouse, mousemask, ungetmouse,
- mouseinterval, and wenclose relating to mouse interfacing
- are not part of XPG4, nor are they present in SVr4. See
- the curs_mouse(3x) manual page for details.
- The routine mcprint was not present in any previous curses
- implementation. See the curs_print(3x) manual page for
- details.
+
+
+ Override the compiled-in assumption that the terminal's
+ default colors are white-on-black (see default_col-
+ ors(3x)). You may set the foreground and background color
+ values with this environment variable by proving a 2-ele-
+ ment list: foreground,background. For example, to tell
+ ncurses to not assume anything about the colors, set this
+ to "-1,-1". To make it green-on-black, set it to "2,0".
+ Any positive value from zero to the terminfo max_colors
+ value is allowed.
+
- The routine wresize is not part of XPG4, nor is it present
- in SVr4. See the wresize(3x) manual page for details.
+
+
+ This applies only to the MinGW port of ncurses.
- In historic curses versions, delays embedded in the
- capabilities cr, ind, cub1, ff and tab activated
- corresponding delay bits in the UNIX tty driver. In this
- implementation, all padding is done by NUL sends. This
- method is slightly more expensive, but narrows the
- interface to the UNIX kernel significantly and increases
- the package's portability correspondingly.
+ The Console2 program's handling of the Microsoft Console
+ API call CreateConsoleScreenBuffer is defective. Applica-
+ tions which use this will hang. However, it is possible
+ to simulate the action of this call by mapping coordi-
+ nates, explicitly saving and restoring the original screen
+ contents. Setting the environment variable NCGDB has the
+ same effect.
-NOTES
- The header file <curses.h> automatically includes the
- header files <stdio.h> and <unctrl.h>.
+
+ This applies only to ncurses configured to use the GPM
+ interface.
- If standard output from a ncurses program is re-directed
- to something which is not a tty, screen updates will be
- directed to standard error. This was an undocumented
- feature of AT&T System V Release 3 curses.
+ If present, the environment variable is a list of one or
+ more terminal names against which the TERM environment
+ variable is matched. Setting it to an empty value dis-
+ ables the GPM interface; using the built-in support for
+ xterm, etc.
+
+ If the environment variable is absent, ncurses will
+ attempt to open GPM if TERM contains "linux".
-AUTHORS
- Zeyd M. Ben-Halim, Eric S. Raymond, Thomas E. Dickey.
- Based on pcurses by Pavel Curtis.
+
+ Ncurses may use tabs as part of the cursor movement opti-
+ mization. In some cases, your terminal driver may not
+ handle these properly. Set this environment variable to
+ disable the feature. You can also adjust your stty set-
+ tings to avoid the problem. NCURSES_NO_MAGIC_COOKIE Some
+ terminals use a magic-cookie feature which requires spe-
+ cial handling to make highlighting and other video
+ attributes display properly. You can suppress the high-
+ lighting entirely for these terminals by setting this
+ environment variable.
+
+
+ Most of the terminal descriptions in the terminfo database
+ are written for real "hardware" terminals. Many people
+ use terminal emulators which run in a windowing environ-
+ ment and use curses-based applications. Terminal emula-
+ tors can duplicate all of the important aspects of a hard-
+ ware terminal, but they do not have the same limitations.
+ The chief limitation of a hardware terminal from the
+ standpoint of your application is the management of
+ dataflow, i.e., timing. Unless a hardware terminal is
+ interfaced into a terminal concentrator (which does flow
+ control), it (or your application) must manage dataflow,
+ preventing overruns. The cheapest solution (no hardware
+ cost) is for your program to do this by pausing after
+ operations that the terminal does slowly, such as clearing
+ the display.
+
+ As a result, many terminal descriptions (including the
+ vt100) have delay times embedded. You may wish to use
+ these descriptions, but not want to pay the performance
+ penalty.
+
+ Set the NCURSES_NO_PADDING environment variable to disable
+ all but mandatory padding. Mandatory padding is used as a
+ part of special control sequences such as flash.
+
+
+ This setting is obsolete. Before changes
+
+ o started with 5.9 patch 20120825 and
+ o continued though 5.9 patch 20130126
+ ncurses enabled buffered output during terminal initial-
+ ization. This was done (as in SVr4 curses) for perfor-
+ mance reasons. For testing purposes, both of ncurses and
+ certain applications, this feature was made optional.
+ Setting the NCURSES_NO_SETBUF variable disabled output
+ buffering, leaving the output in the original (usually
+ line buffered) mode.
+ In the current implementation, ncurses performs its own
+ buffering and does not require this workaround. It does
+ not modify the buffering of the standard output.
+ The reason for the change was to make the behavior for
+ interrupts and other signals more robust. One drawback is
+ that certain nonconventional programs would mix ordinary
+ stdio calls with ncurses calls and (usually) work. This
+ is no longer possible since ncurses is not using the
+ buffered standard output but its own output (to the same
+ file descriptor). As a special case, the low-level calls
+ such as putp still use the standard output. But high-
+ level curses calls do not.
+
+
+ During initialization, the ncurses library checks for spe-
+ cial cases where VT100 line-drawing (and the corresponding
+ alternate character set capabilities) described in the
+ terminfo are known to be missing. Specifically, when run-
+ ning in a UTF-8 locale, the Linux console emulator and the
+ GNU screen program ignore these. Ncurses checks the TERM
+ environment variable for these. For other special cases,
+ you should set this environment variable. Doing this
+ tells ncurses to use Unicode values which correspond to
+ the VT100 line-drawing glyphs. That works for the special
+ cases cited, and is likely to work for terminal emulators.
+
+ When setting this variable, you should set it to a nonzero
+ value. Setting it to zero (or to a nonnumber) disables
+ the special check for "linux" and "screen".
+
+ As an alternative to the environment variable, ncurses
+ checks for an extended terminfo capability U8. This is a
+ numeric capability which can be compiled using tic -x.
+ For example
+
+ # linux console, if patched to provide working
+ # VT100 shift-in/shift-out, with corresponding font.
+ linux-vt100|linux console with VT100 line-graphics,
+ U8#0, use=linux,
+
+ # uxterm with vt100Graphics resource set to false
+ xterm-utf8|xterm relying on UTF-8 line-graphics,
+ U8#1, use=xterm,
+
+ The name "U8" is chosen to be two characters, to permit it
+ to be used by applications that use ncurses' termcap
+ interface.
+
+
+
+
+ During initialization, the ncurses debugging library
+ checks the NCURSES_TRACE environment variable. If it is
+ defined, to a numeric value, ncurses calls the trace func-
+ tion, using that value as the argument.
+ The argument values, which are defined in curses.h, pro-
+ vide several types of information. When running with
+ traces enabled, your application will write the file trace
+ to the current directory.
+ See curs_trace(3x) for more information.
+
+
+ Denotes your terminal type. Each terminal type is dis-
+ tinct, though many are similar.
+
+ TERM is commonly set by terminal emulators to help appli-
+ cations find a workable terminal description. Some of
+ those choose a popular approximation, e.g., "ansi",
+ "vt100", "xterm" rather than an exact fit. Not infre-
+ quently, your application will have problems with that
+ approach, e.g., incorrect function-key definitions.
+
+ If you set TERM in your environment, it has no effect on
+ the operation of the terminal emulator. It only affects
+ the way applications work within the terminal. Likewise,
+ as a general rule (xterm being a rare exception), terminal
+ emulators which allow you to specify TERM as a parameter
+ or configuration value do not change their behavior to
+ match that setting.
+
+
+
+
+ If the ncurses library has been configured with termcap
+ support, ncurses will check for a terminal's description
+ in termcap form if it is not available in the terminfo
+ database.
+
+ The TERMCAP environment variable contains either a termi-
+ nal description (with newlines stripped out), or a file
+ name telling where the information denoted by the TERM
+ environment variable exists. In either case, setting it
+ directs ncurses to ignore the usual place for this infor-
+ mation, e.g., /etc/termcap.
+
+
+
+
+ Overrides the directory in which ncurses searches for your
+ terminal description. This is the simplest, but not the
+ only way to change the list of directories. The complete
+ list of directories in order follows:
+ o the last directory to which ncurses wrote, if any,
+ is searched first
+ o the directory specified by the TERMINFO environment
+ variable
+ o $HOME/.terminfo
+ o directories listed in the TERMINFO_DIRS environment
+ variable
+
+ o one or more directories whose names are configured
+ and compiled into the ncurses library, i.e.,
+
+ o /usr/local/ncurses/share/ter-
+ minfo:/usr/share/terminfo (corresponding to the
+ TERMINFO_DIRS variable)
+
+ o /usr/share/terminfo (corresponding to the TER-
+ MINFO variable)
+
+
+
+
+ Specifies a list of directories to search for terminal
+ descriptions. The list is separated by colons (i.e., ":")
+ on Unix, semicolons on OS/2 EMX.
+
+ All of the terminal descriptions are in terminfo form.
+ Normally these are stored in a directory tree, using sub-
+ directories named by the first letter of the terminal
+ names therein.
+
+ If ncurses is built with a hashed database, then each
+ entry in this list can also be the path of the correspond-
+ ing database file.
+
+ If ncurses is built with a support for reading termcap
+ files directly, then an entry in this list may be the path
+ of a termcap file.
+
+
+
+
+ If TERMCAP does not hold a file name then ncurses checks
+ the TERMPATH environment variable. This is a list of
+ filenames separated by spaces or colons (i.e., ":") on
+ Unix, semicolons on OS/2 EMX.
+
+ If the TERMPATH environment variable is not set, ncurses
+ looks in the files /etc/termcap, /usr/share/misc/termcap
+ and $HOME/.termcap, in that order.
+
+ The library may be configured to disregard the following
+ variables when the current user is the superuser (root),
+ or if the application uses setuid or setgid permissions:
+
+ $TERMINFO, $TERMINFO_DIRS, $TERMPATH, as well as $HOME.
+
+
+ Several different configurations are possible, depending
+ on the configure script options used when building
+ ncurses. There are a few main options whose effects are
+ visible to the applications developer using ncurses:
+
+ --disable-overwrite
+ The standard include for ncurses is as noted in SYN-
+ OPSIS:
+
+ #include <curses.h>
+
+ This option is used to avoid filename conflicts when
+ ncurses is not the main implementation of curses of
+ the computer. If ncurses is installed disabling
+ overwrite, it puts its headers in a subdirectory,
+ e.g.,
+
+ #include <ncurses/curses.h>
+
+ It also omits a symbolic link which would allow you
+ to use -lcurses to build executables.
+
+ --enable-widec
+ The configure script renames the library and (if the
+ --disable-overwrite option is used) puts the header
+ files in a different subdirectory. All of the
+ library names have a "w" appended to them, i.e.,
+ instead of
+
+ -lncurses
+
+ you link with
+
+ -lncursesw
+
+ You must also define _XOPEN_SOURCE_EXTENDED when com-
+ piling for the wide-character library to use the
+ extended (wide-character) functions. The curses.h
+ file which is installed for the wide-character
+ library is designed to be compatible with the normal
+ library's header. Only the size of the WINDOW struc-
+ ture differs, and very few applications require more
+ than a pointer to WINDOWs. If the headers are
+ installed allowing overwrite, the wide-character
+ library's headers should be installed last, to allow
+ applications to be built using either library from
+ the same set of headers.
+
+ --with-pthread
+ The configure script renames the library. All of the
+ library names have a "t" appended to them (before any
+ "w" added by --enable-widec).
+
+ The global variables such as LINES are replaced by
+ macros to allow read-only access. At the same time,
+ setter-functions are provided to set these values.
+ Some applications (very few) may require changes to
+ work with this convention.
+
+ --with-shared
+
+ --with-normal
+
+ --with-debug
+
+ --with-profile
+ The shared and normal (static) library names differ
+ by their suffixes, e.g., libncurses.so and libn-
+ curses.a. The debug and profiling libraries add a
+ "_g" and a "_p" to the root names respectively, e.g.,
+ libncurses_g.a and libncurses_p.a.
+
+ --with-trace
+ The trace function normally resides in the debug
+ library, but it is sometimes useful to configure this
+ in the shared library. Configure scripts should
+ check for the function's existence rather than assum-
+ ing it is always in the debug library.
+
+
+ /usr/share/tabset
+ directory containing initialization files for the
+ terminal capability database /usr/share/terminfo ter-
+ minal capability database
+
+
+ terminfo(5) and related pages whose names begin "curs_"
+ for detailed routine descriptions.
+ curs_variables(3x)
+
+
+ The ncurses library can be compiled with an option
+ (-DUSE_GETCAP) that falls back to the old-style /etc/term-
+ cap file if the terminal setup code cannot find a terminfo
+ entry corresponding to TERM. Use of this feature is not
+ recommended, as it essentially includes an entire termcap
+ compiler in the ncurses startup code, at significant cost
+ in core and startup cycles.
+ The ncurses library includes facilities for capturing
+ mouse events on certain terminals (including xterm). See
+ the curs_mouse(3x) manual page for details.
+ The ncurses library includes facilities for responding to
+ window resizing events, e.g., when running in an xterm.
+ See the resizeterm(3x) and wresize(3x) manual pages for
+ details. In addition, the library may be configured with
+ a SIGWINCH handler.
+ The ncurses library extends the fixed set of function key
+ capabilities of terminals by allowing the application
+ designer to define additional key sequences at runtime.
+ See the define_key(3x) key_defined(3x), and keyok(3x) man-
+ ual pages for details.
+
+ The ncurses library can exploit the capabilities of termi-
+ nals which implement the ISO-6429 SGR 39 and SGR 49 con-
+ trols, which allow an application to reset the terminal to
+ its original foreground and background colors. From the
+ users' perspective, the application is able to draw col-
+ ored text on a background whose color is set indepen-
+ dently, providing better control over color contrasts.
+ See the default_colors(3x) manual page for details.
+
+ The ncurses library includes a function for directing
+ application output to a printer attached to the terminal
+ device. See the curs_print(3x) manual page for details.
+
+
+ The ncurses library is intended to be BASE-level confor-
+ mant with XSI Curses. The EXTENDED XSI Curses functional-
+ ity (including color support) is supported.
+ A small number of local differences (that is, individual
+ differences between the XSI Curses and ncurses calls) are
+ described in PORTABILITY sections of the library man
+ pages.
+ Unlike other implementations, this one checks parameters
+ such as pointers to WINDOW structures to ensure they are
+ not null. The main reason for providing this behavior is
+ to guard against programmer error. The standard interface
+ does not provide a way for the library to tell an applica-
+ tion which of several possible errors were detected.
+ Relying on this (or some other) extension will adversely
+ affect the portability of curses applications.
+ This implementation also contains several extensions:
+ o The routine has_key is not part of XPG4, nor is it
+ present in SVr4. See the curs_getch(3x) manual page
+ for details.
+ o The routine slk_attr is not part of XPG4, nor is it
+ present in SVr4. See the curs_slk(3x) manual page for
+ details.
+ o The routines getmouse, mousemask, ungetmouse, mousein-
+ terval, and wenclose relating to mouse interfacing are
+ not part of XPG4, nor are they present in SVr4. See
+ the curs_mouse(3x) manual page for details.
+ o The routine mcprint was not present in any previous
+ curses implementation. See the curs_print(3x) manual
+ page for details.
+ o The routine wresize is not part of XPG4, nor is it
+ present in SVr4. See the wresize(3x) manual page for
+ details.
+ o The WINDOW structure's internal details can be hidden
+ from application programs. See curs_opaque(3x) for
+ the discussion of is_scrollok, etc.
+ o This implementation can be configured to provide rudi-
+ mentary support for multi-threaded applications. See
+ curs_threads(3x) for details.
+ o This implementation can also be configured to provide
+ a set of functions which improve the ability to manage
+ multiple screens. See curs_sp_funcs(3x) for details.
+ In historic curses versions, delays embedded in the capa-
+ bilities cr, ind, cub1, ff and tab activated corresponding
+ delay bits in the UNIX tty driver. In this implementa-
+ tion, all padding is done by sending NUL bytes. This
+ method is slightly more expensive, but narrows the inter-
+ face to the UNIX kernel significantly and increases the
+ package's portability correspondingly.
+
+
+ The header file <curses.h> automatically includes the
+ header files <stdio.h> and <unctrl.h>.
+ If standard output from a ncurses program is re-directed
+ to something which is not a tty, screen updates will be
+ directed to standard error. This was an undocumented fea-
+ ture of AT&T System V Release 3 curses.
+
+
+ Zeyd M. Ben-Halim, Eric S. Raymond, Thomas E. Dickey.
+ Based on pcurses by Pavel Curtis.
+ ncurses(3x)
-
-
-Man(1) output converted with
-man2html
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+