@@ -60,7 +60,7 @@
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.
- This describes ncurses version 6.4 (patch 20230819).
+ This describes ncurses version 6.4 (patch 20231014).
The ncurses library emulates the curses library of System V Release 4
UNIX, and XPG4 (X/Open Portability Guide) curses (also known as XSI
@@ -119,68 +119,69 @@
Before a curses program is run, the tab stops of the terminal should be
set and its initialization strings, if defined, must be output. This
can be done by executing the tputinit command after the shell
- environment variable TERM has been exported. tset(1) is usually
- responsible for doing this. [See terminfo(5) for further details.]
+ environment variable TERM has been exported. (The BSD-style tset(1)
+ utility also performs this function.) See subsection "Tabs and
+ Initialization" of terminfo(5).
- 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.
+ 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.
- 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.
+ 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 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 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.
+ 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 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.
- After using routines to manipulate a window, refresh(3x) 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
+ After using routines to manipulate a window, refresh(3x) 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. 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
+ 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 <curses.h>, such as A_REVERSE, ACS_HLINE,
+ 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 <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 affect a program running in an AT&T 630 layer,
- for example, where the size of a screen is changeable (see
+ 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 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
+ 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
/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 set to $HOME/myterms,
+ (The a is copied from the first letter of att4424 to avoid creation of
+ huge directories.) However, if TERMINFO is set to $HOME/myterms,
curses first checks
$HOME/myterms/a/att4424,
@@ -189,98 +190,98 @@
/usr/share/terminfo/a/att4424.
- This is useful for developing experimental definitions or when write
+ This is useful for developing experimental definitions or when write
permission in /usr/share/terminfo is not available.
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
+ be filled in by initscr with the size of the screen. The constants
TRUE and FALSE have the values 1 and 0, respectively.
- 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 curscr can be used in only a few
+ 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 curscr can be used in only a few
routines.
- Many curses routines have two or more versions. The routines prefixed
+ 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.
- The routines prefixed with mv require a y and x coordinate to move to
+ 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.
+ 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 specified before the
+ The routines prefixed with mvw take both a window argument 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;
+ In each case, win is the window affected, and pad is the pad affected;
win and pad are always pointers to type WINDOW.
- Option setting routines require a Boolean flag bf with the value TRUE
- or FALSE; bf is always of type bool. Most of the data types used in
- the library routines, such as WINDOW, SCREEN, bool, and chtype are
- defined in <curses.h>. Types used for the terminfo routines such as
+ Option setting routines require a Boolean flag bf with the value TRUE
+ or FALSE; bf is always of type bool. Most of the data types used in
+ the library routines, such as WINDOW, 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
+ 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 characters. The
- normal (8-bit) library stores characters combined with
+ the "normal" library, which handles 8-bit characters. The
+ normal (8-bit) library stores characters combined with
attributes in chtype data.
- Attributes alone (no corresponding character) may be stored in
+ 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 multibyte
- characters (see the section on ALTERNATECONFIGURATIONS). The
- "wide" library includes all of the calls from the "normal"
- library. It adds about one third more calls using data types
+ the so-called "wide" library, which handles multibyte
+ characters (see the section on ALTERNATECONFIGURATIONS). 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
+ 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
+ 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
+ Each cell (row and column) in a WINDOW is stored as a
cchar_t.
- The setcchar(3x) and getcchar(3x) functions store and
+ The setcchar(3x) and getcchar(3x) functions store and
retrieve the data from a cchar_t structure.
wchar_t
- stores a "wide" character. Like chtype, this may be an
+ 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
+ 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
+ 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.
- Routines that return an integer return ERR upon failure and an integer
+ 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.
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
+ 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).
- Functions with a "mv" prefix first perform a cursor movement using
+ Functions with a "mv" prefix first perform a cursor movement using
wmove, and return an error if the position is outside the window, or if
- the window pointer is null. Most "mv"-prefixed functions (except
- variadic functions such as mvprintw) are provided both as macros and
+ the window pointer is null. Most "mv"-prefixed functions (except
+ variadic functions such as mvprintw) are provided both as macros and
functions.
Routines that return pointers return NULL on error.
- The following environment symbols are useful for customizing the
- runtime behavior of the ncurses library. The most important ones have
+ 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.
- When set, change occurrences of the command_character (i.e., the cmdch
- capability) of the loaded terminfo entries to the value of this
+ 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
@@ -797,33 +798,33 @@
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
+ 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.
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
+ 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. This is not always possible because your application may be
- running on a host which does not honor NAWS (Negotiations About Window
+ 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
+ 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 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
+ 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 all use of external environment
+ 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.
@@ -831,31 +832,31 @@
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
+ 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
+ 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
+ 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 implementation provides a
- global variable with the same name. Portable applications should not
- rely upon the presence of ESCDELAY in either form, but setting the
- environment variable rather than the global variable does not create
+ global variable with the same name. Portable applications should not
+ rely upon the presence of ESCDELAY in either form, but setting the
+ environment variable rather than the global variable does not create
problems when compiling an application.
- Tells ncurses where your home directory is. That is where it may read
+ Tells ncurses where your home directory is. That is where it may read
and write auxiliary terminal descriptions:
$HOME/.termcap
@@ -863,13 +864,13 @@
- Like COLUMNS, specify the height of the screen in characters. See
+ Like COLUMNS, specify the height of the screen in characters. See
COLUMNS for a detailed description.
- 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
+ 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
@@ -877,37 +878,37 @@
3 = middle.
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
+ numeric digits 1-3 in any order, e.g., 123 or 321. If it is not
specified, ncurses uses 132.
- Override the compiled-in assumption that the terminal's default colors
- are white-on-black (see 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
+ Override the compiled-in assumption that the terminal's default colors
+ are white-on-black (see 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.
This applies only to the MinGW port of ncurses.
- The Console2 program's handling of the Microsoft Console API call
- CreateConsoleScreenBuffer is defective. Applications which use this
+ The Console2 program's handling of the Microsoft Console API call
+ CreateConsoleScreenBuffer is defective. Applications which use this
will hang. However, it is possible to simulate the action of this call
- by mapping coordinates, explicitly saving and restoring the original
- screen contents. Setting the environment variable NCGDB has the same
+ by mapping coordinates, explicitly saving and restoring the original
+ screen contents. Setting the environment variable NCGDB has the same
effect.
This applies only to ncurses configured to use the GPM interface.
- 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 disables the GPM interface; using the built-in
+ 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 disables the GPM interface; using the built-in
support for xterm, etc.
If the environment variable is absent, ncurses will attempt to open GPM
@@ -915,39 +916,39 @@
- Ncurses may use tabs as part of the cursor movement optimization. In
- some cases, your terminal driver may not handle these properly. Set
- this environment variable to disable the feature. You can also adjust
+ Ncurses may use tabs as part of the cursor movement optimization. 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(1) settings to avoid the problem.
- Some terminals use a magic-cookie feature which requires special
- handling to make highlighting and other video attributes display
+ Some terminals use a magic-cookie feature which requires special
+ handling to make highlighting and other video attributes display
properly. You can suppress the highlighting 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
+ 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
+ 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
+ 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
+ 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.
@@ -958,44 +959,44 @@
o continued though 5.9 patch 20130126
- ncurses enabled buffered output during terminal initialization. This
- was done (as in SVr4 curses) for performance 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)
+ ncurses enabled buffered output during terminal initialization. This
+ was done (as in SVr4 curses) for performance 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
+ 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
+ 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 special cases
+ During initialization, the ncurses library checks for special cases
where VT100 line-drawing (and the corresponding alternate character set
- capabilities) described in the terminfo are known to be missing.
- Specifically, when running 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
+ capabilities) described in the terminfo are known to be missing.
+ Specifically, when running 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
+ 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
+ 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
+ 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
@@ -1007,67 +1008,67 @@
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
+ 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 function, using that value as the
+ During initialization, the ncurses debugging library checks the
+ NCURSES_TRACE environment variable. 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
+ 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.
See curs_trace(3x) for more information.
- Denotes your terminal type. Each terminal type is distinct, though
+ Denotes your terminal type. Each terminal type is distinct, though
many are similar.
- TERM is commonly set by terminal emulators to help applications find a
- workable terminal description. Some of those choose a popular
+ TERM is commonly set by terminal emulators to help applications find a
+ workable terminal description. Some of those choose a popular
approximation, e.g., "ansi", "vt100", "xterm" rather than an exact fit.
Not infrequently, 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(1) being a
- rare exception), terminal emulators which allow you to specify TERM as
- a parameter or configuration value do not change their behavior to
+ 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(1) 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
+ 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 terminal description
- (with newlines stripped out), or a file name telling where the
+ (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
+ case, setting it directs ncurses to ignore the usual place for this
information, e.g., /etc/termcap.
- ncurses can be configured to read from multiple terminal databases.
- The TERMINFO variable overrides the location for the default terminal
- database. Terminal descriptions (in terminal format) are stored in
+ ncurses can be configured to read from multiple terminal databases.
+ The TERMINFO variable overrides the location for the default terminal
+ database. Terminal descriptions (in terminal format) are stored in
terminal databases:
o Normally these are stored in a directory tree, using subdirectories
named by the first letter of the terminal names therein.
This is the scheme used in System V, which legacy Unix systems use,
- and the TERMINFO variable is used by curses applications on those
+ and the TERMINFO variable is used by curses applications on those
systems to override the default location of the terminal database.
- o If ncurses is built to use hashed databases, then each entry in
+ o If ncurses is built to use hashed databases, then each entry in
this list may be the path of a hashed database file, e.g.,
/usr/share/terminfo.db
@@ -1076,30 +1077,30 @@
/usr/share/terminfo/
- The hashed database uses less disk-space and is a little faster
- than the directory tree. However, some applications assume the
- existence of the directory tree, reading it directly rather than
+ The hashed database uses less disk-space and is a little faster
+ than the directory tree. However, some applications assume the
+ existence of the directory tree, reading it directly rather than
using the terminfo library calls.
- o 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
+ o 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.
o If the TERMINFO variable begins with "hex:" or "b64:", ncurses uses
- the remainder of that variable as a compiled terminal description.
+ the remainder of that variable as a compiled terminal description.
You might produce the base64 format using infocmp(1m):
TERMINFO="$(infocmp -0 -Q2 -q)"
export TERMINFO
- The compiled description is used if it corresponds to the terminal
+ The compiled description is used if it corresponds to the terminal
identified by the TERM variable.
- Setting TERMINFO is the simplest, but not the only way to set location
- of the default terminal database. The complete list of database
+ Setting TERMINFO is the simplest, but not the only way to set location
+ of the default terminal database. The complete list of database
locations in order follows:
- o the last terminal database to which ncurses wrote, if any, is
+ o the last terminal database to which ncurses wrote, if any, is
searched first
o the location specified by the TERMINFO environment variable
@@ -1108,31 +1109,31 @@
o locations listed in the TERMINFO_DIRS environment variable
- o one or more locations whose names are configured and compiled
+ o one or more locations whose names are configured and compiled
into the ncurses library, i.e.,
- o /usr/share/terminfo (corresponding to the TERMINFO_DIRS
+ o /usr/share/terminfo (corresponding to the TERMINFO_DIRS
variable)
o /usr/share/terminfo (corresponding to the TERMINFO variable)
- Specifies a list of locations to search for terminal descriptions.
- Each location in the list is a terminal database as described in the
- section on the TERMINFO variable. The list is separated by colons
+ Specifies a list of locations to search for terminal descriptions.
+ Each location in the list is a terminal database as described in the
+ section on the TERMINFO variable. The list is separated by colons
(i.e., ":") on Unix, semicolons on OS/2 EMX.
- There is no corresponding feature in System V terminfo; it is an
+ There is no corresponding feature in System V terminfo; it is an
extension developed for ncurses.
- If TERMCAP does not hold a file name then ncurses checks the TERMPATH
- environment variable. This is a list of filenames separated by spaces
+ 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
+ If the TERMPATH environment variable is not set, ncurses looks in the
files
/etc/termcap, /usr/share/misc/termcap and $HOME/.termcap,
@@ -1140,16 +1141,16 @@
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
+ 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
+ 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
@@ -1157,20 +1158,20 @@
#include<curses.h>
- This option is used to avoid filename conflicts when ncurses is
+ 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
+ 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
+ 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"
+ 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
@@ -1179,45 +1180,45 @@
-lncursesw
- You must also enable the wide-character features in the header
- file when compiling for the wide-character library to use the
- extended (wide-character) functions. The symbol which enables
+ You must also enable the wide-character features in the header
+ file when compiling for the wide-character library to use the
+ extended (wide-character) functions. The symbol which enables
these features has changed since XSI Curses, Issue 4:
- o Originally, the wide-character feature required the symbol
+ o Originally, the wide-character feature required the symbol
_XOPEN_SOURCE_EXTENDED but that was only valid for XPG4
(1996).
- o Later, that was deemed conflicting with _XOPEN_SOURCE defined
+ o Later, that was deemed conflicting with _XOPEN_SOURCE defined
to 500.
- o As of mid-2018, none of the features in this implementation
- require a _XOPEN_SOURCE feature greater than 600. However,
+ o As of mid-2018, none of the features in this implementation
+ require a _XOPEN_SOURCE feature greater than 600. However,
X/Open Curses, Issue 7 (2009) recommends defining it to 700.
- o Alternatively, you can enable the feature by defining
- NCURSES_WIDECHAR with the caveat that some other header file
- than curses.h may require a specific value for _XOPEN_SOURCE
+ o Alternatively, you can enable the feature by defining
+ NCURSES_WIDECHAR with the caveat that some other header file
+ than curses.h may require a specific value for _XOPEN_SOURCE
(or a system-specific symbol).
- 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 structure differs, and very
+ 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 structure 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
+ 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
+ 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
+ to set these values. Some applications (very few) may require
changes to work with this convention.
--with-shared
@@ -1227,17 +1228,17 @@
--with-debug
--with-profile
- The shared and normal (static) library names differ by their
- suffixes, e.g., libncurses.so and libncurses.a. The debug and
- profiling libraries add a "_g" and a "_p" to the root names
+ The shared and normal (static) library names differ by their
+ suffixes, e.g., libncurses.so and libncurses.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-termlib
- Low-level functions which do not depend upon whether the library
+ Low-level functions which do not depend upon whether the library
supports wide-characters, are provided in the tinfo library.
- By doing this, it is possible to share the tinfo library between
- wide/normal configurations as well as reduce the size of the
+ By doing this, it is possible to share the tinfo library between
+ wide/normal configurations as well as reduce the size of the
library when only low-level functions are needed.
Those functions are described in these pages:
@@ -1257,24 +1258,18 @@
ocurs_util(3x) - miscellaneous curses utility routines
--with-trace
- The trace function normally resides in the debug library, but it
- is sometimes useful to configure this in the shared library.
+ 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 assuming it is always in the debug library.