<!--
* t
****************************************************************************
- * Copyright 2018-2021,2023 Thomas E. Dickey *
+ * Copyright 2018-2023,2024 Thomas E. Dickey *
* Copyright 1998-2015,2017 Free Software Foundation, Inc. *
* *
* Permission is hereby granted, free of charge, to any person obtaining a *
* sale, use or other dealings in this Software without prior written *
* authorization. *
****************************************************************************
- * @Id: ncurses.3x,v 1.189 2023/12/23 16:32:37 tom Exp @
- * X/Open Curses Issue 7 assumes some optimization will be done, but
- * does not mandate it in any way.
+ * @Id: ncurses.3x,v 1.210 2024/04/20 21:24:19 tom Exp @
-->
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN">
<HTML>
<HEAD>
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii">
<meta name="generator" content="Manpage converted by man2html - see https://invisible-island.net/scripts/readme.html#others_scripts">
-<TITLE>ncurses 3x 2023-12-23 ncurses 6.4 Library calls</TITLE>
+<TITLE>ncurses 3x 2024-04-20 ncurses 6.4 Library calls</TITLE>
<link rel="author" href="mailto:bug-ncurses@gnu.org">
</HEAD>
<BODY>
-<H1 class="no-header">ncurses 3x 2023-12-23 ncurses 6.4 Library calls</H1>
+<H1 class="no-header">ncurses 3x 2024-04-20 ncurses 6.4 Library calls</H1>
<PRE>
<STRONG><A HREF="ncurses.3x.html">ncurses(3x)</A></STRONG> Library calls <STRONG><A HREF="ncurses.3x.html">ncurses(3x)</A></STRONG>
</PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
- The <EM>ncurses</EM> library routines give the user a terminal-independent
- method of updating character screens with reasonable optimization.
- This implementation is "new curses" (<EM>ncurses</EM>) and is the approved
- replacement for 4.4BSD classic curses, which has been discontinued.
- This describes <EM>ncurses</EM> version 6.4 (patch 20231223).
-
- The <EM>ncurses</EM> library emulates the curses library of System V Release 4
- Unix ("SVr4"), and XPG4 (X/Open Portability Guide) curses (also known
- as XSI curses). XSI stands for X/Open System Interfaces Extension.
- The <EM>ncurses</EM> library is freely redistributable in source form.
-
- <EM>ncurses</EM> man pages employ several sections to clarify matters of usage
+ The "new curses" library offers the programmer a terminal-independent
+ means of reading keyboard and mouse input and updating character-cell
+ terminals with output optimized to minimize screen updates. <EM>ncurses</EM>
+ replaces the <EM>curses</EM> libraries from System V Release 4 Unix ("SVr4") and
+ 4.4BSD Unix, the development of which ceased in the 1990s. This
+ document describes <EM>ncurses</EM> version 6.4 (patch 20240420).
+
+ <EM>ncurses</EM> permits control of the terminal screen's contents; abstraction
+ and subdivision thereof with <EM>windows</EM> and <EM>pads</EM>; the reading of terminal
+ input; control of terminal input and output options; environment query
+ routines; color manipulation; the definition and use of <EM>soft</EM> <EM>label</EM>
+ keys; <EM>terminfo</EM> capability access; a <EM>termcap</EM> compatibility interface;
+ and an abstraction of the system's API for manipulating the terminal
+ (such as <STRONG>termios(3)</STRONG>).
+
+ <EM>ncurses</EM> implements the standard interface described by X/Open Curses
+ Issue 7. In many behavioral details not standardized by X/Open,
+ <EM>ncurses</EM> emulates the <EM>curses</EM> library of SVr4 and provides numerous
+ useful extensions.
+
+ <EM>ncurses</EM> man pages employ several sections to clarify matters of usage
and interoperability with other <EM>curses</EM> implementations.
- <STRONG>o</STRONG> "NOTES" describes matters and caveats of which any user of the
- <EM>ncurses</EM> API should be aware, such as limitations on the size of an
- underlying integral type or the availability of a preprocessor
- macro for a function (which prevents its address from being taken).
- This section also describes implementation details that will be
- significant to the programmer but which are not standardized.
+ <STRONG>o</STRONG> "NOTES" describes issues and caveats of which any user of the
+ <EM>ncurses</EM> API should be aware, such as limitations on the size of an
+ underlying integral type or the availability of a preprocessor
+ macro exclusive of a function definition (which prevents its
+ address from being taken). This section also describes
+ implementation details that will be significant to the programmer
+ but which are not standardized.
<STRONG>o</STRONG> "EXTENSIONS" presents <EM>ncurses</EM> innovations beyond the X/Open Curses
standard and/or the SVr4 <EM>curses</EM> implementation. They are termed
state.
<STRONG>o</STRONG> "PORTABILITY" discusses matters (beyond the exercise of extensions)
- that should be considered when writing to a <EM>curses</EM> standard, or to
+ that should be considered when writing to a <EM>curses</EM> standard, or for
multiple implementations.
<STRONG>o</STRONG> "HISTORY" examines points of detail in <EM>ncurses</EM> and other <EM>curses</EM>
where precedent or inertia have frustrated better design (and, in a
few cases, where such inertia has been overcome).
- A program using these routines must be linked with the <STRONG>-lncurses</STRONG>
- option, or (if it has been generated) with the debugging library
- <STRONG>-lncurses_g</STRONG>. (Your system integrator may also have installed these
- libraries under the names <STRONG>-lcurses</STRONG> and <STRONG>-lcurses_g</STRONG>.) The ncurses_g
- library generates trace logs (in a file called "trace" in the current
- directory) that describe curses actions. See section "ALTERNATE
- CONFIGURATIONS" below.
+ A <EM>curses</EM> application must be linked with the library; use the <STRONG>-lncurses</STRONG>
+ option to your compiler or linker. A debugging version of the library
+ may be available; if so, link with it using <STRONG>-lncurses_g</STRONG>. (Your system
+ integrator may have installed these libraries such that you can use the
+ options <STRONG>-lcurses</STRONG> and <STRONG>-lcurses_g</STRONG>, respectively.) The <EM>ncurses</EM><STRONG>_</STRONG><EM>g</EM> library
+ generates trace logs (in a file called <EM>trace</EM> in the current directory)
+ that describe <EM>ncurses</EM> actions. See section "ALTERNATE CONFIGURATIONS"
+ below.
- The <EM>ncurses</EM> package supports: overall screen, window and pad
- manipulation; output to windows and pads; reading terminal input;
- control over terminal and <STRONG>curses</STRONG> input and output options; environment
- query routines; color manipulation; use of soft label keys; terminfo
- capabilities; and access to low-level terminal-manipulation routines.
+</PRE><H3><a name="h3-Application-Structure">Application Structure</a></H3><PRE>
+ A <EM>curses</EM> application uses information from the system locale;
+ <STRONG>setlocale(3)</STRONG> prepares it for <EM>curses</EM> library calls.
-</PRE><H3><a name="h3-Initialization">Initialization</a></H3><PRE>
- The library uses the locale which the calling program has initialized.
- That is normally done with <STRONG>setlocale(3)</STRONG>:
-
- <STRONG>setlocale(LC_ALL,</STRONG> <STRONG>"");</STRONG>
+ 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.
+ If the locale is not thus initialized, the library assumes that
+ characters are printable as in ISO 8859-1, to work with certain legacy
+ programs. You should initialize the locale; do not expect consistent
+ behavior from the library when the locale has not been set up.
- The function <STRONG>initscr</STRONG> or <STRONG>newterm</STRONG> must be called to initialize the
- library before any of the other routines that deal with windows and
- screens are used. The routine <STRONG><A HREF="curs_initscr.3x.html">endwin(3x)</A></STRONG> must be called before
- exiting.
+ <STRONG><A HREF="curs_initscr.3x.html">initscr(3x)</A></STRONG> or <STRONG><A HREF="curs_initscr.3x.html">newterm(3x)</A></STRONG> must be called to initialize <EM>curses</EM> before
+ use of any functions that deal with windows and screens.
- To get character-at-a-time input without echoing (most interactive,
- screen oriented programs want this), the following sequence should be
- used:
+ To get character-at-a-time input without echoing--most interactive,
+ screen-oriented programs want this--use the following sequence.
- <STRONG>initscr();</STRONG> <STRONG>cbreak();</STRONG> <STRONG>noecho();</STRONG>
+ initscr(); cbreak(); noecho();
- Most programs would additionally use the sequence:
+ Most applications perform further setup as follows.
- <STRONG>intrflush(stdscr,</STRONG> <STRONG>FALSE);</STRONG>
- <STRONG>keypad(stdscr,</STRONG> <STRONG>TRUE);</STRONG>
+ intrflush(stdscr, FALSE);
+ keypad(stdscr, TRUE);
- Before a <STRONG>curses</STRONG> 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 <STRONG>tput</STRONG> <STRONG>init</STRONG> command after the shell
- environment variable <EM>TERM</EM> has been exported. (The BSD-style <STRONG><A HREF="tset.1.html">tset(1)</A></STRONG>
- utility also performs this function.) See subsection "Tabs and
- Initialization" of <STRONG><A HREF="terminfo.5.html">terminfo(5)</A></STRONG>.
+ A <EM>curses</EM> program then often enters an event loop of some sort. Call
+ <STRONG><A HREF="curs_initscr.3x.html">endwin(3x)</A></STRONG> before exiting.
</PRE><H3><a name="h3-Overview">Overview</a></H3><PRE>
size as the terminal screen, is always available. Create others with
<STRONG><A HREF="curs_window.3x.html">newwin(3x)</A></STRONG>.
- A <EM>curses</EM> library does not manage overlapping windows. (See <STRONG><A HREF="panel.3x.html">panel(3x)</A></STRONG>
- if you desire this.) You can either use <STRONG>stdscr</STRONG> to manage one screen-
- filling window, or tile the screen into non-overlapping windows and not
- use <STRONG>stdscr</STRONG> at all. Mixing the two approaches will result in
- unpredictable, and undesired, effects.
+ A <EM>curses</EM> library does not manage overlapping windows (but see below).
+ You can either use <STRONG>stdscr</STRONG> to manage one screen-filling window, or tile
+ the screen into non-overlapping windows and not use <STRONG>stdscr</STRONG> at all.
+ Mixing the two approaches will result in unpredictable and undesired
+ effects.
Functions permit manipulation of a window and the <EM>cursor</EM> identifying
the cell within it at which the next output operation will occur.
Among those, the most basic are <STRONG><A HREF="curs_move.3x.html">move(3x)</A></STRONG> and <STRONG><A HREF="curs_addch.3x.html">addch(3x)</A></STRONG>: these place the
- cursor and write a character to <STRONG>stdscr</STRONG>, respectively. As a rule,
- window-addressing functions feature names prefixed (or infixed, see
- below) with "w"; these allow the user to specify a pointer to a <EM>WINDOW.</EM>
- Counterparts not thus prefixed (or infixed) affect <STRONG>stdscr</STRONG>. Because
- moving the cursor prior to another operation is so common, <EM>curses</EM>
- generally also provides functions with a "mv" prefix as a convenience.
- Thus, the library defines all of <STRONG>addch</STRONG>, <STRONG>waddch</STRONG>, <STRONG>mvaddch</STRONG>, and <STRONG>mvwaddch</STRONG>.
- When both prefixes are present, the order of arguments is a <EM>WINDOW</EM>
- pointer first, then a <EM>y</EM> and <EM>x</EM> coordinate pair.
-
- Updating the terminal screen with every <EM>curses</EM> call can cause
- unpleasant flicker or inefficient use of the communications channel to
- the device. Therefore, after using <EM>curses</EM> functions to accumulate a
- set of desired updates that make sense to present together, call
- <STRONG><A HREF="curs_refresh.3x.html">refresh(3x)</A></STRONG> to tell the library to make the user's screen look like
- <STRONG>stdscr</STRONG>. <EM>ncurses</EM> <EM>optimizes</EM> its output by computing a minimal number of
- operations to mutate the screen from its state at the previous refresh
- to the new one. Effective optimization demands accurate information
- about the terminal device: the management of such information is the
- province of the <STRONG><A HREF="curs_terminfo.3x.html">terminfo(3x)</A></STRONG> API, a feature of every standard <EM>curses</EM>
- implementation.
+ cursor and write a character to <STRONG>stdscr</STRONG>, respectively.
+
+ Frequent changes to the terminal screen can cause unpleasant flicker or
+ inefficient use of the communication channel to the device, so the
+ library does not generally update it automatically. Therefore, after
+ using <EM>curses</EM> functions to accumulate a set of desired updates that make
+ sense to present together, call <STRONG><A HREF="curs_refresh.3x.html">refresh(3x)</A></STRONG> to tell the library to make
+ the user's screen look like <STRONG>stdscr</STRONG>. The library <EM>optimizes</EM> its output
+ by computing a minimal number of operations to mutate the screen from
+ its state at the previous refresh to the new one. Effective
+ optimization demands accurate information about the terminal device:
+ the management of such information is the province of the <STRONG><A HREF="curs_terminfo.3x.html">terminfo(3x)</A></STRONG>
+ API, a feature of every standard <EM>curses</EM> implementation.
Special windows called <EM>pads</EM> may also be manipulated. These are windows
that are not constrained to the size of the terminal screen and whose
modes as underlined, in reverse video, or in color on terminals that
support such display enhancements. See <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG>.
- <EM>curses</EM> predefines constants for a small set of line-drawing and other
- graphics corresponding to the DEC Alternate Character Set (ACS), a
- feature of VT100 and other terminals. See <STRONG><A HREF="curs_addch.3x.html">waddch(3x)</A></STRONG> and <STRONG><A HREF="curs_add_wch.3x.html">wadd_wch(3x)</A></STRONG>.
+ <EM>curses</EM> predefines constants for a small set of forms-drawing graphics
+ corresponding to the DEC Alternate Character Set (ACS), a feature of
+ VT100 and other terminals. See <STRONG><A HREF="curs_addch.3x.html">waddch(3x)</A></STRONG>.
<EM>curses</EM> is implemented using the operating system's terminal driver;
keystroke events are received not as scan codes but as byte sequences.
multibyte <EM>escape</EM> <EM>sequence.</EM> <EM>curses</EM> translates these into unique <EM>key</EM>
<EM>codes.</EM> See <STRONG><A HREF="curs_getch.3x.html">getch(3x)</A></STRONG>.
+ <EM>ncurses</EM> provides reimplementations of the SVr4 <STRONG><A HREF="panel.3x.html">panel(3x)</A></STRONG>, <STRONG><A HREF="form.3x.html">form(3x)</A></STRONG>, and
+ <STRONG><A HREF="menu.3x.html">menu(3x)</A></STRONG> libraries to ease construction of user interfaces with <EM>curses</EM>.
+
+
+</PRE><H3><a name="h3-Initialization">Initialization</a></H3><PRE>
+ The selection of an appropriate value of <EM>TERM</EM> in the process
+ environment is essential to correct <EM>curses</EM> and <EM>terminfo</EM> library
+ operation. A well-configured system selects a correct <EM>TERM</EM> value
+ automatically; <STRONG><A HREF="tset.1.html">tset(1)</A></STRONG> may assist with troubleshooting exotic
+ situations.
-</PRE><H3><a name="h3-Effects-of-GUIs-and-Environment-Variables">Effects of GUIs and Environment Variables</a></H3><PRE>
- The selection of an approprate value of <EM>TERM</EM> in the process environment
- is essential to correct <EM>curses</EM> and <EM>terminfo</EM> library operation. A well-
- configured system selects a correct <EM>TERM</EM> value automatically; <STRONG><A HREF="tset.1.html">tset(1)</A></STRONG>
- may assist with troubleshooting exotic situations.
+ If you change the terminal type, export the <EM>TERM</EM> environment variable
+ in the shell, then run <STRONG><A HREF="tset.1.html">tset(1)</A></STRONG> or the "<STRONG>tput</STRONG> <STRONG>init</STRONG>" command. See
+ subsection "Tabs and Initialization" of <STRONG><A HREF="terminfo.5.html">terminfo(5)</A></STRONG>.
If the environment variables <EM>LINES</EM> and <EM>COLUMNS</EM> are set, or if the
<EM>curses</EM> program is executing in a graphical windowing environment, the
</PRE><H3><a name="h3-Naming-Conventions">Naming Conventions</a></H3><PRE>
- Many <EM>curses</EM> functions have two or more versions. Those prefixed with
- "w" require a window argument. Four functions prefixed with "p"
- require a pad argument. Those without a prefix generally operate on
- <STRONG>stdscr</STRONG>.
+ <EM>curses</EM> offers many functions in variant forms using a regular set of
+ alternatives to the name of an elemental one. Those prefixed with "w"
+ require a <EM>WINDOW</EM> pointer argument; those with a "mv" prefix first
+ perform cursor movement using <STRONG><A HREF="curs_move.3x.html">wmove(3x)</A></STRONG>; a "mvw" prefix indicates both.
+ The "w" function is typically the elemental one; the removal of this
+ prefix usually indicates operation on <STRONG>stdscr</STRONG>.
+
+ Four functions prefixed with "p" require a pad argument.
In function synopses, <EM>ncurses</EM> man pages apply the following names to
parameters.
- <EM>bf</EM> <EM>bool</EM> (<STRONG>TRUE</STRONG> or <STRONG>FALSE</STRONG>)
- <EM>win</EM> pointer to <EM>WINDOW</EM>
- <EM>pad</EM> pointer to <EM>WINDOW</EM> that is a pad
+ <EM>bf</EM> <EM>bool</EM> (<STRONG>TRUE</STRONG> or <STRONG>FALSE</STRONG>)
+ <EM>c</EM> a <EM>char</EM> or <EM>int</EM>
+ <EM>ch</EM> a <EM>chtype</EM>
+ <EM>wc</EM> a <EM>wchar</EM><STRONG>_</STRONG><EM>t</EM> or <EM>wint</EM><STRONG>_</STRONG><EM>t</EM>
+ <EM>wch</EM> a <EM>cchar</EM><STRONG>_</STRONG><EM>t</EM>
+ <EM>win</EM> pointer to a <EM>WINDOW</EM>
+ <EM>pad</EM> pointer to a <EM>WINDOW</EM> that is a pad
</PRE><H3><a name="h3-Wide-and-Non-wide-Character-Configurations">Wide and Non-wide Character Configurations</a></H3><PRE>
<EM>ncurses</EM> is the library in its "non-wide" configuration, handling only
eight-bit characters. It stores a character combined with
- attributes in a <EM>chtype</EM> datum.
+ attributes in a <EM>chtype</EM> datum, which is often an alias of <EM>int</EM>.
Attributes alone (with no corresponding character) can be
stored in variables of <EM>chtype</EM> or <EM>attr</EM><STRONG>_</STRONG><EM>t</EM> type. In either
case, they are represented as an integral bit mask.
- Each cell of a <EM>WINDOW</EM> is stored as a <EM>chtype.</EM>
+ Each cell of a <EM>WINDOW</EM> is stored as a <EM>chtype</EM>.
<EM>ncursesw</EM> is the library in its "wide" configuration, which handles
character encodings requiring a larger data type than <EM>char</EM> (a
calls using additional data types that can store such
<EM>multibyte</EM> characters.
- <EM>cchar</EM><STRONG>_</STRONG><EM>t</EM> corresponds to the non-wide configuration's <EM>chtype.</EM>
+ <EM>cchar</EM><STRONG>_</STRONG><EM>t</EM> corresponds to the non-wide configuration's <EM>chtype</EM>.
It always a structure type, because it stores more
- data than can fit into an integer. A character code
- may be larger than can fit in a C <EM>char,</EM> and moreover
- more than one character may occupy a cell (as with
- accent marks and other diacritics). Each character
- is of type <EM>wchar</EM><STRONG>_</STRONG><EM>t;</EM> a complex character contains one
- spacing character and zero or more non-spacing
- characters (see below). Attributes and color data
- are stored in separate fields of the structure, not
- combined as in <EM>chtype.</EM>
-
- Each cell (row and column) <EM>WINDOW</EM> is stored as a
- <EM>cchar</EM><STRONG>_</STRONG><EM>t.</EM>
-
- The <STRONG><A HREF="curs_getcchar.3x.html">setcchar(3x)</A></STRONG> and <STRONG><A HREF="curs_getcchar.3x.html">getcchar(3x)</A></STRONG> functions store and
- retrieve the data from a <EM>cchar</EM><STRONG>_</STRONG><EM>t</EM> structure. The wide library
- API of <EM>ncurses</EM> depends on two data types standardized by ISO
- C95.
-
- <EM>wchar</EM><STRONG>_</STRONG><EM>t</EM> stores a wide character. Like <EM>chtype,</EM> this may be
- an integer. Depending on the character encoding, a
- wide character may be <EM>spacing,</EM> meaning that it
+ data than fit into a standard scalar type. A
+ character code may not be representable as a <EM>char</EM>,
+ and moreover more than one character may occupy a
+ cell (as with accent marks and other diacritics).
+ Each character is of type <EM>wchar</EM><STRONG>_</STRONG><EM>t</EM>; a complex
+ character contains one spacing character and zero or
+ more non-spacing characters (see below). Attributes
+ and color data are stored in separate fields of the
+ structure, not combined as in <EM>chtype</EM>.
+
+ Each cell of a <EM>WINDOW</EM> is stored as a <EM>cchar</EM><STRONG>_</STRONG><EM>t</EM>.
+
+ <STRONG><A HREF="curs_getcchar.3x.html">setcchar(3x)</A></STRONG> and <STRONG><A HREF="curs_getcchar.3x.html">getcchar(3x)</A></STRONG> store and retrieve <EM>cchar</EM><STRONG>_</STRONG><EM>t</EM>
+ data. The wide library API of <EM>ncurses</EM> depends on two data
+ types standardized by ISO C95.
+
+ <EM>wchar</EM><STRONG>_</STRONG><EM>t</EM> stores a wide character. Like <EM>chtype</EM>, it may be an
+ alias of <EM>int</EM>. Depending on the character encoding,
+ a wide character may be <EM>spacing</EM>, meaning that it
occupies a character cell by itself and typically
- accompanies cursor advancement on input, or
- <EM>combining,</EM> meaning that it occupies the same cell as
- a spacing character, is often regarded as a
- "modifier" of the base glyph with which it combines,
- and typically does not advance the cursor on input.
+ accompanies cursor advancement, or <EM>non-spacing</EM>,
+ meaning that it occupies the same cell as a spacing
+ character, is often regarded as a "modifier" of the
+ base glyph with which it combines, and typically
+ does not advance the cursor.
<EM>wint</EM><STRONG>_</STRONG><EM>t</EM> can store a <EM>wchar</EM><STRONG>_</STRONG><EM>t</EM> or the constant <STRONG>WEOF</STRONG>,
analogously to the <EM>int</EM>-sized character manipulation
regular naming convention relates many of the wide variants
to their non-wide counterparts; where a non-wide function
name contains "ch" or "str", prefix it with "_w" to obtain
- the wide counterpart. For example, <STRONG>waddch</STRONG> becomes <STRONG>wadd_wch</STRONG>.
+ the wide counterpart. For example, <STRONG>waddch</STRONG> becomes <STRONG>wadd_wch</STRONG>.
+ (Exceptions that add only "w" comprise <STRONG>addwstr</STRONG>, <STRONG>inwstr</STRONG>, and
+ their variants.)
This convention is inapplicable to some non-wide function
names, so other transformations are used for the wide
- configuration: in the window background management functions,
+ configuration: the window background management function
"bkgd" becomes "bkgrnd"; the window border-drawing and
- -clearing functions are suffixed with "_set".
+ -clearing functions are suffixed with "_set"; and character
+ attribute manipulation functions like "attron" become
+ "attr_on".
</PRE><H3><a name="h3-Function-Name-Index">Function Name Index</a></H3><PRE>
<STRONG><EM>curses</EM></STRONG> Function Name Man Page
---------------------------------------------
COLOR_PAIR <STRONG><A HREF="curs_color.3x.html">curs_color(3x)</A></STRONG>
- PAIR_NUMBER <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG>
+ PAIR_NUMBER <STRONG><A HREF="curs_color.3x.html">curs_color(3x)</A></STRONG>
add_wch <STRONG><A HREF="curs_add_wch.3x.html">curs_add_wch(3x)</A></STRONG>
add_wchnstr <STRONG><A HREF="curs_add_wchstr.3x.html">curs_add_wchstr(3x)</A></STRONG>
add_wchstr <STRONG><A HREF="curs_add_wchstr.3x.html">curs_add_wchstr(3x)</A></STRONG>
doupdate <STRONG><A HREF="curs_refresh.3x.html">curs_refresh(3x)</A></STRONG>
dupwin <STRONG><A HREF="curs_window.3x.html">curs_window(3x)</A></STRONG>
echo <STRONG><A HREF="curs_inopts.3x.html">curs_inopts(3x)</A></STRONG>
+
echo_wchar <STRONG><A HREF="curs_add_wch.3x.html">curs_add_wch(3x)</A></STRONG>
echochar <STRONG><A HREF="curs_addch.3x.html">curs_addch(3x)</A></STRONG>
endwin <STRONG><A HREF="curs_initscr.3x.html">curs_initscr(3x)</A></STRONG>
erasewchar <STRONG><A HREF="curs_termattrs.3x.html">curs_termattrs(3x)</A></STRONG>
exit_curses <STRONG><A HREF="curs_memleaks.3x.html">curs_memleaks(3x)</A></STRONG>*
exit_terminfo <STRONG><A HREF="curs_memleaks.3x.html">curs_memleaks(3x)</A></STRONG>*
-
extended_color_content <STRONG><A HREF="curs_color.3x.html">curs_color(3x)</A></STRONG>*
extended_pair_content <STRONG><A HREF="curs_color.3x.html">curs_color(3x)</A></STRONG>*
extended_slk_color <STRONG><A HREF="curs_slk.3x.html">curs_slk(3x)</A></STRONG>*
flash <STRONG><A HREF="curs_beep.3x.html">curs_beep(3x)</A></STRONG>
flushinp <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>
free_pair <STRONG><A HREF="new_pair.3x.html">new_pair(3x)</A></STRONG>*
+ get_escdelay <STRONG><A HREF="curs_threads.3x.html">curs_threads(3x)</A></STRONG>*
get_wch <STRONG><A HREF="curs_get_wch.3x.html">curs_get_wch(3x)</A></STRONG>
get_wstr <STRONG><A HREF="curs_get_wstr.3x.html">curs_get_wstr(3x)</A></STRONG>
getattrs <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG>
init_pair <STRONG><A HREF="curs_color.3x.html">curs_color(3x)</A></STRONG>
initscr <STRONG><A HREF="curs_initscr.3x.html">curs_initscr(3x)</A></STRONG>
innstr <STRONG><A HREF="curs_instr.3x.html">curs_instr(3x)</A></STRONG>
+
innwstr <STRONG><A HREF="curs_inwstr.3x.html">curs_inwstr(3x)</A></STRONG>
ins_nwstr <STRONG><A HREF="curs_ins_wstr.3x.html">curs_ins_wstr(3x)</A></STRONG>
ins_wch <STRONG><A HREF="curs_ins_wch.3x.html">curs_ins_wch(3x)</A></STRONG>
insertln <STRONG><A HREF="curs_deleteln.3x.html">curs_deleteln(3x)</A></STRONG>
insnstr <STRONG><A HREF="curs_insstr.3x.html">curs_insstr(3x)</A></STRONG>
insstr <STRONG><A HREF="curs_insstr.3x.html">curs_insstr(3x)</A></STRONG>
-
instr <STRONG><A HREF="curs_instr.3x.html">curs_instr(3x)</A></STRONG>
intrflush <STRONG><A HREF="curs_inopts.3x.html">curs_inopts(3x)</A></STRONG>
inwstr <STRONG><A HREF="curs_inwstr.3x.html">curs_inwstr(3x)</A></STRONG>
mvget_wch <STRONG><A HREF="curs_get_wch.3x.html">curs_get_wch(3x)</A></STRONG>
mvget_wstr <STRONG><A HREF="curs_get_wstr.3x.html">curs_get_wstr(3x)</A></STRONG>
mvgetch <STRONG><A HREF="curs_getch.3x.html">curs_getch(3x)</A></STRONG>
+
mvgetn_wstr <STRONG><A HREF="curs_get_wstr.3x.html">curs_get_wstr(3x)</A></STRONG>
mvgetnstr <STRONG><A HREF="curs_getstr.3x.html">curs_getstr(3x)</A></STRONG>
mvgetstr <STRONG><A HREF="curs_getstr.3x.html">curs_getstr(3x)</A></STRONG>
mvin_wchnstr <STRONG><A HREF="curs_in_wchstr.3x.html">curs_in_wchstr(3x)</A></STRONG>
mvin_wchstr <STRONG><A HREF="curs_in_wchstr.3x.html">curs_in_wchstr(3x)</A></STRONG>
mvinch <STRONG><A HREF="curs_inch.3x.html">curs_inch(3x)</A></STRONG>
-
mvinchnstr <STRONG><A HREF="curs_inchstr.3x.html">curs_inchstr(3x)</A></STRONG>
mvinchstr <STRONG><A HREF="curs_inchstr.3x.html">curs_inchstr(3x)</A></STRONG>
mvinnstr <STRONG><A HREF="curs_instr.3x.html">curs_instr(3x)</A></STRONG>
mvwprintw <STRONG><A HREF="curs_printw.3x.html">curs_printw(3x)</A></STRONG>
mvwscanw <STRONG><A HREF="curs_scanw.3x.html">curs_scanw(3x)</A></STRONG>
mvwvline <STRONG><A HREF="curs_border.3x.html">curs_border(3x)</A></STRONG>
+
mvwvline_set <STRONG><A HREF="curs_border_set.3x.html">curs_border_set(3x)</A></STRONG>
napms <STRONG><A HREF="curs_kernel.3x.html">curs_kernel(3x)</A></STRONG>
newpad <STRONG><A HREF="curs_pad.3x.html">curs_pad(3x)</A></STRONG>
nocbreak <STRONG><A HREF="curs_inopts.3x.html">curs_inopts(3x)</A></STRONG>
nodelay <STRONG><A HREF="curs_inopts.3x.html">curs_inopts(3x)</A></STRONG>
noecho <STRONG><A HREF="curs_inopts.3x.html">curs_inopts(3x)</A></STRONG>
-
nofilter <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>*
nonl <STRONG><A HREF="curs_inopts.3x.html">curs_inopts(3x)</A></STRONG>
noqiflush <STRONG><A HREF="curs_inopts.3x.html">curs_inopts(3x)</A></STRONG>
scroll <STRONG><A HREF="curs_scroll.3x.html">curs_scroll(3x)</A></STRONG>
scrollok <STRONG><A HREF="curs_outopts.3x.html">curs_outopts(3x)</A></STRONG>
set_curterm <STRONG><A HREF="curs_terminfo.3x.html">curs_terminfo(3x)</A></STRONG>
+ set_escdelay <STRONG><A HREF="curs_threads.3x.html">curs_threads(3x)</A></STRONG>*
+ set_tabsize <STRONG><A HREF="curs_threads.3x.html">curs_threads(3x)</A></STRONG>*
set_term <STRONG><A HREF="curs_initscr.3x.html">curs_initscr(3x)</A></STRONG>
setcchar <STRONG><A HREF="curs_getcchar.3x.html">curs_getcchar(3x)</A></STRONG>
setscrreg <STRONG><A HREF="curs_outopts.3x.html">curs_outopts(3x)</A></STRONG>
slk_init <STRONG><A HREF="curs_slk.3x.html">curs_slk(3x)</A></STRONG>
slk_label <STRONG><A HREF="curs_slk.3x.html">curs_slk(3x)</A></STRONG>
slk_noutrefresh <STRONG><A HREF="curs_slk.3x.html">curs_slk(3x)</A></STRONG>
+
slk_refresh <STRONG><A HREF="curs_slk.3x.html">curs_slk(3x)</A></STRONG>
slk_restore <STRONG><A HREF="curs_slk.3x.html">curs_slk(3x)</A></STRONG>
slk_set <STRONG><A HREF="curs_slk.3x.html">curs_slk(3x)</A></STRONG>
subpad <STRONG><A HREF="curs_pad.3x.html">curs_pad(3x)</A></STRONG>
subwin <STRONG><A HREF="curs_window.3x.html">curs_window(3x)</A></STRONG>
syncok <STRONG><A HREF="curs_window.3x.html">curs_window(3x)</A></STRONG>
-
term_attrs <STRONG><A HREF="curs_termattrs.3x.html">curs_termattrs(3x)</A></STRONG>
termattrs <STRONG><A HREF="curs_termattrs.3x.html">curs_termattrs(3x)</A></STRONG>
termname <STRONG><A HREF="curs_termattrs.3x.html">curs_termattrs(3x)</A></STRONG>
use_env <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>
use_extended_names <STRONG><A HREF="curs_extend.3x.html">curs_extend(3x)</A></STRONG>*
use_legacy_coding <STRONG><A HREF="legacy_coding.3x.html">legacy_coding(3x)</A></STRONG>*
+ use_screen <STRONG><A HREF="curs_threads.3x.html">curs_threads(3x)</A></STRONG>*
use_tioctl <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>*
+ use_window <STRONG><A HREF="curs_threads.3x.html">curs_threads(3x)</A></STRONG>*
vid_attr <STRONG><A HREF="curs_terminfo.3x.html">curs_terminfo(3x)</A></STRONG>
vid_puts <STRONG><A HREF="curs_terminfo.3x.html">curs_terminfo(3x)</A></STRONG>
vidattr <STRONG><A HREF="curs_terminfo.3x.html">curs_terminfo(3x)</A></STRONG>
waddnwstr <STRONG><A HREF="curs_addwstr.3x.html">curs_addwstr(3x)</A></STRONG>
waddstr <STRONG><A HREF="curs_addstr.3x.html">curs_addstr(3x)</A></STRONG>
waddwstr <STRONG><A HREF="curs_addwstr.3x.html">curs_addwstr(3x)</A></STRONG>
+
wattr_get <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG>
wattr_off <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG>
wattr_on <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG>
wbkgrndset <STRONG><A HREF="curs_bkgrnd.3x.html">curs_bkgrnd(3x)</A></STRONG>
wborder <STRONG><A HREF="curs_border.3x.html">curs_border(3x)</A></STRONG>
wborder_set <STRONG><A HREF="curs_border_set.3x.html">curs_border_set(3x)</A></STRONG>
-
wchgat <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG>
wclear <STRONG><A HREF="curs_clear.3x.html">curs_clear(3x)</A></STRONG>
wclrtobot <STRONG><A HREF="curs_clear.3x.html">curs_clear(3x)</A></STRONG>
wscanw <STRONG><A HREF="curs_scanw.3x.html">curs_scanw(3x)</A></STRONG>
wscrl <STRONG><A HREF="curs_scroll.3x.html">curs_scroll(3x)</A></STRONG>
wsetscrreg <STRONG><A HREF="curs_outopts.3x.html">curs_outopts(3x)</A></STRONG>
+
wstandend <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG>
wstandout <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG>
wsyncdown <STRONG><A HREF="curs_window.3x.html">curs_window(3x)</A></STRONG>
wvline <STRONG><A HREF="curs_border.3x.html">curs_border(3x)</A></STRONG>
wvline_set <STRONG><A HREF="curs_border_set.3x.html">curs_border_set(3x)</A></STRONG>
- Depending on the configuration, additional sets of functions may be
- available:
-
- <STRONG><A HREF="curs_memleaks.3x.html">curs_memleaks(3x)</A></STRONG> - curses memory-leak checking
+ <EM>ncurses</EM>'s <EM>screen-pointer</EM> <EM>extension</EM> adds additional functions
+ corresponding to many of the above, each with an "_sp" suffix; see
+ <STRONG><A HREF="curs_sp_funcs.3x.html">curs_sp_funcs(3x)</A></STRONG>.
- <STRONG><A HREF="curs_sp_funcs.3x.html">curs_sp_funcs(3x)</A></STRONG> - curses screen-pointer extension
-
- <STRONG><A HREF="curs_threads.3x.html">curs_threads(3x)</A></STRONG> - curses thread support
-
- <STRONG><A HREF="curs_trace.3x.html">curs_trace(3x)</A></STRONG> - curses debugging routines
+ The availability of some extensions is configurable when <EM>ncurses</EM> is
+ compiled; see sections "ALTERNATE CONFIGURATIONS" and "EXTENSIONS"
+ below.
</PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
- Routines that return an integer return <STRONG>ERR</STRONG> upon failure and an integer
- value other than <STRONG>ERR</STRONG> 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 <STRONG>w</STRONG> version, except <STRONG>setscrreg</STRONG>,
- <STRONG>wsetscrreg</STRONG>, <STRONG>getyx</STRONG>, <STRONG>getbegyx</STRONG>, and <STRONG>getmaxyx</STRONG>. The return values of
- <STRONG>setscrreg</STRONG>, <STRONG>wsetscrreg</STRONG>, <STRONG>getyx</STRONG>, <STRONG>getbegyx</STRONG>, and <STRONG>getmaxyx</STRONG> are undefined
- (i.e., these should not be used as the right-hand side of assignment
- statements).
-
- Functions with a "mv" prefix first perform cursor movement using <STRONG>wmove</STRONG>
- and return an error if the position is outside the window, or (for
- "mvw" functions) if the <EM>WINDOW</EM> pointer is null. Most "mv"-prefixed
- functions (except variadic functions such as <STRONG>mvprintw</STRONG>) are provided
- both as macros and functions.
-
- Routines that return pointers return <STRONG>NULL</STRONG> on error.
+ Unless otherwise noted, functions that return an integer return <STRONG>OK</STRONG> on
+ success and <STRONG>ERR</STRONG> on failure. Functions that return pointers return <STRONG>NULL</STRONG>
+ on failure. Typically, <EM>ncurses</EM> treats a null pointer passed as a
+ function parameter as a failure. Functions prefixed with "mv" first
+ perform cursor movement and fail if the position (<EM>y</EM>, <EM>x</EM>) is outside the
+ window boundaries.
</PRE><H2><a name="h2-ENVIRONMENT">ENVIRONMENT</a></H2><PRE>
- The following environment symbols are useful for customizing the
- runtime behavior of the <EM>ncurses</EM> library. The most important ones have
- been already discussed in detail.
+ The following symbols from the process environment customize the
+ runtime behavior of <EM>ncurses</EM> applications. The library may be
+ configured to disregard the variables <EM>TERMINFO</EM>, <EM>TERMINFO</EM><STRONG>_</STRONG><EM>DIRS</EM>,
+ <EM>TERMPATH</EM>, and <EM>HOME</EM>, if the user is the superuser (root), or the
+ application uses <STRONG>setuid(2)</STRONG> or <STRONG>setgid(2)</STRONG>.
-</PRE><H3><a name="h3-CC-command-character"><EM>CC</EM> command-character</a></H3><PRE>
- When set, change occurrences of the command_character (i.e., the <STRONG>cmdch</STRONG>
- capability) of the loaded terminfo entries to the value of this
- variable. Very few terminfo entries provide this feature.
+</PRE><H3><a name="h3-BAUDRATE"><EM>BAUDRATE</EM></a></H3><PRE>
+ The debugging library checks this variable when the application has
+ redirected output to a file. Its integral value is used for the baud
+ rate. If that value is absent or invalid, <EM>ncurses</EM> uses 9600. This
+ feature allows testers to construct repeatable test cases that take
+ into account optimization decisions that depend on baud rate.
- Because this name is also used in development environments to represent
- the C compiler's name, <EM>ncurses</EM> ignores it if it does not happen to be a
- single character.
+</PRE><H3><a name="h3-CC-_command-character_"><EM>CC</EM> (command character)</a></H3><PRE>
+ When set, the <STRONG>command_character</STRONG> (<STRONG>cmdch</STRONG>) capability value of loaded
+ <EM>terminfo</EM> entries changes to the value of this variable. Very few <EM>term-</EM>
+ <EM>info</EM> entries provide this feature.
-</PRE><H3><a name="h3-BAUDRATE"><EM>BAUDRATE</EM></a></H3><PRE>
- 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, <EM>ncurses</EM> uses
- 9600. This allows testers to construct repeatable test-cases that take
- into account costs that depend on baudrate.
+ Because this name is also used in development environments to represent
+ the C compiler's name, <EM>ncurses</EM> ignores its value if it is not one
+ character in length.
</PRE><H3><a name="h3-COLUMNS"><EM>COLUMNS</EM></a></H3><PRE>
- 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 <EM>COLUMNS</EM> value nor
- the terminal's screen size is available, <EM>ncurses</EM> uses the size which
- may be specified in the terminfo database (i.e., the <STRONG>cols</STRONG> 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 <EM>COLUMNS</EM> and/or <EM>LINES</EM> overrides the library's use of
- the screen size obtained from the operating system.
-
- Either <EM>COLUMNS</EM> or <EM>LINES</EM> 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, <STRONG>lines</STRONG> and <STRONG>cols</STRONG> should not be specified in a terminal
- description for terminals which are run as emulations.
-
- Use the <STRONG>use_env</STRONG> function to disable all use of external environment
- (but not including system calls) to determine the screen size. Use the
- <STRONG>use_tioctl</STRONG> function to update <EM>COLUMNS</EM> or <EM>LINES</EM> to match the screen size
- obtained from system calls or the terminal database.
+ This variable specifies 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 <EM>COLUMNS</EM>
+ is not defined and the terminal's screen size is not available from the
+ terminal driver, <EM>ncurses</EM> uses the size specified by the <STRONG>columns</STRONG> (<STRONG>cols</STRONG>)
+ capability of the terminal type's entry in the <EM>terminfo</EM> database, if
+ any.
+
+ It is important that your application use the correct screen size.
+ Automatic detection thereof is not always possible because an
+ application may be running on a host that does not honor NAWS
+ (Negotiations About Window Size) or as a different user ID than the
+ owner of the terminal device file. Setting <EM>COLUMNS</EM> and/or <EM>LINES</EM>
+ overrides the library's use of the screen size obtained from the
+ operating system.
+
+ The <EM>COLUMNS</EM> and <EM>LINES</EM> variables may be specified independently. This
+ property is useful to circumvent misfeatures of legacy terminal type
+ descriptions; <STRONG>xterm(1)</STRONG> descriptions specifying 65 lines were once
+ notorious. For best results, avoid specifying <STRONG>cols</STRONG> and <STRONG>lines</STRONG>
+ capability codes in <EM>terminfo</EM> descriptions of terminal emulators.
+
+ <STRONG><A HREF="curs_util.3x.html">use_env(3x)</A></STRONG> can disable use of the process environment in determining
+ the screen size. <STRONG><A HREF="curs_util.3x.html">use_tioctl(3x)</A></STRONG> can update <EM>COLUMNS</EM> and <EM>LINES</EM> to match
+ the screen size obtained from system calls or the terminal database.
</PRE><H3><a name="h3-ESCDELAY"><EM>ESCDELAY</EM></a></H3><PRE>
- Specifies the total time, in milliseconds, for which <EM>ncurses</EM> 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.
-
- 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 <STRONG>ESCDELAY</STRONG> in either form, but setting the
- environment variable rather than the global variable does not create
- problems when compiling an application.
+ For <EM>curses</EM> to distinguish the ESC character resulting from a user's
+ press of the "Escape" key on the input device from one beginning an
+ <EM>escape</EM> <EM>sequence</EM> (as commonly produced by function keys), it waits after
+ receiving the escape character to see if further characters are
+ available on the input stream within a short interval. A global
+ variable <STRONG>ESCDELAY</STRONG> stores this interval in milliseconds. The default
+ value of 1000 (one second) is adequate for most uses. This environment
+ variable overrides it.
+
+ The most common instance where you may wish to change this value is to
+ work with a remote host over a slow communication channel. If the host
+ running a <EM>curses</EM> application does not receive the characters of an
+ escape sequence in a timely manner, the library can interpret them as
+ multiple key stroke events.
+
+ <STRONG>xterm(1)</STRONG> mouse events are a form of escape sequence; therefore, if your
+ application makes heavy use of multiple-clicking, you may wish to
+ lengthen the default value because the delay applies to the composite
+ multi-click event as well as the individual clicks.
+
+ Portable applications should not rely upon the presence of <STRONG>ESCDELAY</STRONG> in
+ either form, but setting the environment variable rather than the
+ global variable does not create problems when compiling an application.
+
+ If <STRONG><A HREF="curs_inopts.3x.html">keypad(3x)</A></STRONG> is disabled for the <EM>curses</EM> window receiving input, a
+ program must disambiguate escape sequences itself.
</PRE><H3><a name="h3-HOME"><EM>HOME</EM></a></H3><PRE>
- Tells <EM>ncurses</EM> where your home directory is. That is where it may read
- and write auxiliary terminal descriptions:
-
- $HOME/.termcap
- $HOME/.terminfo
+ <EM>ncurses</EM> may read and write auxiliary terminal descriptions in <EM>.termcap</EM>
+ and <EM>.terminfo</EM> files in the user's home directory.
</PRE><H3><a name="h3-LINES"><EM>LINES</EM></a></H3><PRE>
- Like <EM>COLUMNS</EM>, specify the height of the screen in characters. See
- <EM>COLUMNS</EM> for a detailed description.
+ This counterpart to <EM>COLUMNS</EM> specifies the height of the screen in
+ characters. The corresponding <EM>terminfo</EM> capability and code is <STRONG>lines</STRONG>.
+ See the description of the <EM>COLUMNS</EM> variable above.
</PRE><H3><a name="h3-MOUSE_BUTTONS_123"><EM>MOUSE_BUTTONS_123</EM></a></H3><PRE>
- 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 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, <EM>ncurses</EM> uses 132.
+ (OS/2 EMX port only) OS/2 numbers a three-button mouse inconsistently
+ with other platforms, such that 1 is the left button, 2 the right, and
+ 3 the middle. This variable customizes the mouse button numbering.
+ Its value must be three digits 1-3 in any order. By default, <EM>ncurses</EM>
+ assumes a numbering of "132".
</PRE><H3><a name="h3-NCURSES_ASSUMED_COLORS"><EM>NCURSES_ASSUMED_COLORS</EM></a></H3><PRE>
- Override the compiled-in assumption that the terminal's default colors
- are white-on-black (see <STRONG><A HREF="default_colors.3x.html">default_colors(3x)</A></STRONG>). 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 <EM>ncurses</EM> 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 <STRONG>max_colors</STRONG> value is allowed.
+ If set, this variable overrides the <EM>ncurses</EM> library's compiled-in
+ assumption that the terminal's default colors are white on black; see
+ <STRONG><A HREF="default_colors.3x.html">default_colors(3x)</A></STRONG>. Set the foreground and background color values
+ with this environment variable by assigning it two integer values
+ separated by a comma, indicating foregound and background color
+ numbers, respectively.
+ For example, to tell <EM>ncurses</EM> not to assume anything about the colors,
+ use a value of "-1,-1". To make the default color scheme green on
+ black, use "2,0". <EM>ncurses</EM> accepts integral values from -1 up to the
+ value of the <EM>terminfo</EM> <STRONG>max_colors</STRONG> (<STRONG>colors</STRONG>) capability.
-</PRE><H3><a name="h3-NCURSES_CONSOLE2"><EM>NCURSES_CONSOLE2</EM></a></H3><PRE>
- This applies only to the MinGW port of <EM>ncurses</EM>.
- The <STRONG>Console2</STRONG> program's handling of the Microsoft Console API call
- <STRONG>CreateConsoleScreenBuffer</STRONG> 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 <STRONG>NCGDB</STRONG> has the same
- effect.
+</PRE><H3><a name="h3-NCURSES_CONSOLE2"><EM>NCURSES_CONSOLE2</EM></a></H3><PRE>
+ (MinGW port only) The <EM>Console2</EM> program defectively handles the
+ Microsoft Console API call <EM>CreateConsoleScreenBuffer</EM>. Applications
+ that use it 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 <EM>NCGDB</EM>
+ has the same effect.
</PRE><H3><a name="h3-NCURSES_GPM_TERMS"><EM>NCURSES_GPM_TERMS</EM></a></H3><PRE>
- This applies only to <EM>ncurses</EM> configured to use the GPM interface.
-
- If present, the environment variable is a list of one or more terminal
- names against which the <EM>TERM</EM> 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, <EM>ncurses</EM> will attempt to open GPM
- if <EM>TERM</EM> contains "linux".
+ (Linux only) When <EM>ncurses</EM> is configured to use the GPM interface, this
+ variable may list one or more terminal names against which the <EM>TERM</EM>
+ variable (see below) is matched. An empty value disables the GPM
+ interface, using <EM>ncurses</EM>'s built-in support for <STRONG>xterm(1)</STRONG> mouse
+ protocols instead. If the variable is absent, <EM>ncurses</EM> attempts to open
+ GPM if <EM>TERM</EM> contains "linux".
</PRE><H3><a name="h3-NCURSES_NO_HARD_TABS"><EM>NCURSES_NO_HARD_TABS</EM></a></H3><PRE>
- <EM>ncurses</EM> may use tabs as part of cursor movement optimization. In some
- cases, your terminal driver may not handle these properly. Set this
- environment variable to any value to disable the feature. You can also
- adjust your <STRONG>stty(1)</STRONG> settings to avoid the problem.
+ <EM>ncurses</EM> may use tab characters in cursor movement optimization. In
+ some cases, your terminal driver may not handle them properly. Set
+ this environment variable to any value to disable the feature. You can
+ also adjust your <STRONG>stty(1)</STRONG> settings to avoid the problem.
</PRE><H3><a name="h3-NCURSES_NO_MAGIC_COOKIE"><EM>NCURSES_NO_MAGIC_COOKIE</EM></a></H3><PRE>
- 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 to any value.
+ Many terminals store video attributes as a property of a character
+ cell, as <EM>curses</EM> does. Historically, some recorded changes in video
+ attributes as data that logically <EM>occupies</EM> character cells on the
+ display, switching attributes on or off, similarly to tags in a markup
+ language; these are termed "magic cookies", and must be subsequently
+ overprinted. If the <EM>terminfo</EM> entry for your terminal type does not
+ adequately describe its handling of magic cookies, set this variable to
+ any value to instruct <EM>ncurses</EM> to disable attributes entirely.
</PRE><H3><a name="h3-NCURSES_NO_PADDING"><EM>NCURSES_NO_PADDING</EM></a></H3><PRE>
- 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 <EM>NCURSES</EM><STRONG>_</STRONG><EM>NO</EM><STRONG>_</STRONG><EM>PADDING</EM> environment variable to disable all but
- mandatory padding. Mandatory padding is used as a part of special
- control sequences such as <STRONG>flash</STRONG>.
+ Most terminal type descriptions in the <EM>terminfo</EM> database detail
+ hardware devices. Many people use <EM>curses</EM>-based applications in
+ terminal emulator programs that run in a windowing environment. These
+ programs can duplicate all of the important features of a hardware
+ terminal, but often lack their limitations. Chief among these absent
+ drawbacks is the problem of data flow management; that is, limiting the
+ speed of communication to what the hardware could handle. Unless a
+ hardware terminal is interfaced into a terminal concentrator (which
+ does flow control), an application must manage flow control itself to
+ prevent overruns and data loss.
+
+ A solution that comes at no hardware cost is for an application to
+ pause after directing a terminal to execute an operation that it
+ performs slowly, such as clearing the display. Many terminal type
+ descriptions, including that for the VT100, embed delay specifications
+ in capabilities. You may wish to use these temrinal descriptions
+ without paying the performance penalty. Set <EM>NCURSES</EM><STRONG>_</STRONG><EM>NO</EM><STRONG>_</STRONG><EM>PADDING</EM> to any
+ value to disable all but mandatory padding. Mandatory padding is used
+ by such terminal capabilities as <STRONG>flash_screen</STRONG> (<STRONG>flash</STRONG>).
</PRE><H3><a name="h3-NCURSES_NO_SETBUF"><EM>NCURSES_NO_SETBUF</EM></a></H3><PRE>
- This setting is obsolete. Before changes
-
- <STRONG>o</STRONG> started with 5.9 patch 20120825 and
-
- <STRONG>o</STRONG> continued though 5.9 patch 20130126
-
- <EM>ncurses</EM> enabled buffered output during terminal initialization. This
- was done (as in SVr4 curses) for performance reasons. For testing
- purposes, both of <EM>ncurses</EM> and certain applications, this feature was
- made optional. Setting the <EM>NCURSES</EM><STRONG>_</STRONG><EM>NO</EM><STRONG>_</STRONG><EM>SETBUF</EM> variable disabled output
- buffering, leaving the output in the original (usually line buffered)
- mode.
-
- In the current implementation, <EM>ncurses</EM> 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 <STRONG>stdio(3)</STRONG> calls with <EM>ncurses</EM>
- calls and (usually) work. This is no longer possible since <EM>ncurses</EM> 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 <STRONG>putp</STRONG>
- still use the standard output. But high-level curses calls do not.
+ (Obsolete) Prior to internal changes developed in <EM>ncurses</EM> 5.9 (patches
+ 20120825 through 20130126), the library used <STRONG>setbuf(3)</STRONG> to enable fully
+ buffered output when initializing the terminal. This was done, as in
+ SVr4 <EM>curses</EM>, to increase performance. For testing purposes, both of
+ <EM>ncurses</EM> and of certain applications, this feature was made optional.
+ Setting this variable disabled output buffering, leaving the output
+ stream in the original (usually line-buffered) mode.
+
+ Nowadays, <EM>ncurses</EM> performs its own buffering and does not require this
+ workaround; it does not modify the buffering of the standard output
+ stream. This approach makes signal handling, as for interrupts, more
+ robust. A drawback is that certain unconventional programs mixed
+ <STRONG>stdio(3)</STRONG> calls with <EM>ncurses</EM> calls and (usually) got the behavior they
+ expected. This is no longer the case; <EM>ncurses</EM> does not write to the
+ standard output file descriptor through a <EM>stdio</EM>-buffered stream.
+
+ As a special case, low-level API calls such as <STRONG><A HREF="curs_terminfo.3x.html">putp(3x)</A></STRONG> still use the
+ standard output stream. High-level <EM>curses</EM> calls such as <STRONG><A HREF="curs_printw.3x.html">printw(3x)</A></STRONG> do
+ not.
</PRE><H3><a name="h3-NCURSES_NO_UTF8_ACS"><EM>NCURSES_NO_UTF8_ACS</EM></a></H3><PRE>
- During initialization, the <EM>ncurses</EM> 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. <EM>ncurses</EM> <EM>checks</EM> <EM>the</EM>
- <EM>TERM</EM> <EM>environment</EM> <EM>variable</EM> <EM>for</EM> <EM>these.</EM> <EM>For</EM> <EM>other</EM> <EM>special</EM> <EM>cases,</EM> <EM>you</EM>
- <EM>should</EM> <EM>set</EM> <EM>this</EM> <EM>environment</EM> <EM>variable.</EM> <EM>Doing</EM> <EM>this</EM> <EM>tells</EM> <EM>ncurses</EM> <EM>to</EM> <EM>use</EM>
- <EM>Unicode</EM> <EM>values</EM> <EM>which</EM> <EM>correspond</EM> <EM>to</EM> <EM>the</EM> <EM>VT100</EM> <EM>line-drawing</EM> <EM>glyphs.</EM> <EM>That</EM>
- <EM>works</EM> <EM>for</EM> <EM>the</EM> <EM>special</EM> <EM>cases</EM> <EM>cited,</EM> <EM>and</EM> <EM>is</EM> <EM>likely</EM> <EM>to</EM> <EM>work</EM> <EM>for</EM> <EM>terminal</EM>
- <EM>emulators.</EM>
-
- 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, <EM>ncurses</EM> checks for an
- extended terminfo capability <STRONG>U8</STRONG>. This is a numeric capability which
- can be compiled using <STRONG>tic</STRONG> <STRONG>-x</STRONG>. For example
+ At initialization, <EM>ncurses</EM> inspects the <EM>TERM</EM> environment variable for
+ special cases where VT100 forms-drawing characters (and the
+ corresponding alternate character set <EM>terminfo</EM> capabilities) are known
+ to be unsupported by terminal types that otherwise claim VT100
+ compatibility. Specifically, when running in a UTF-8 locale, the Linux
+ virtual console device and the GNU <STRONG>screen(1)</STRONG> program ignore them. Set
+ this variable to a nonzero value to instruct <EM>ncurses</EM> that the
+ terminal's ACS support is broken; the library then outputs Unicode code
+ points that correspond to the forms-drawing characters. Set it to zero
+ (or a non-integer) to disable the special check for terminal type names
+ matching "linux" or "screen", directing <EM>ncurses</EM> to assume that the ACS
+ feature works if the terminal type description advertises it.
+
+ As an alternative to use of this variable, <EM>ncurses</EM> checks for an
+ extended <EM>terminfo</EM> numeric capability <STRONG>U8</STRONG> that can be compiled using "<STRONG>tic</STRONG>
+ <STRONG>-x</STRONG>". Examples follow.
# linux console, if patched to provide working
# VT100 shift-in/shift-out, with corresponding font.
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 <EM>ncurses</EM>' termcap interface.
+ The two-character name "U8" was chosen to permit its use via <EM>ncurses</EM>'s
+ <EM>termcap</EM> interface.
</PRE><H3><a name="h3-NCURSES_TRACE"><EM>NCURSES_TRACE</EM></a></H3><PRE>
- During initialization, the <EM>ncurses</EM> debugging library checks the
- <EM>NCURSES</EM><STRONG>_</STRONG><EM>TRACE</EM> environment variable. If it is defined, to a numeric
- value, <EM>ncurses</EM> calls the <STRONG>trace</STRONG> function, using that value as the
- argument.
-
- The argument values, which are defined in <STRONG>curses.h</STRONG>, provide several
- types of information. When running with traces enabled, your
- application will write the file <STRONG>trace</STRONG> to the current directory.
-
- See <STRONG><A HREF="curs_trace.3x.html">curs_trace(3x)</A></STRONG> for more information.
+ At initialization, <EM>ncurses</EM> (in its debugging configuration) checks for
+ this variable's presence. If defined with an integral value, the
+ library calls <STRONG><A HREF="curs_trace.3x.html">curses_trace(3x)</A></STRONG> with that value as the argument.
</PRE><H3><a name="h3-TERM"><EM>TERM</EM></a></H3><PRE>
- Denotes your terminal type. Each terminal type is distinct, though
- many are similar.
-
- <EM>TERM</EM> 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 <EM>TERM</EM> 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 (<STRONG>xterm(1)</STRONG> being a
- rare exception), terminal emulators which allow you to specify <EM>TERM</EM> as
- a parameter or configuration value do not change their behavior to
- match that setting.
+ The <EM>TERM</EM> variable denotes the terminal type. Each is distinct, though
+ many are similar. It is commonly set by terminal emulators to help
+ applications find a workable terminal description. Some choose a
+ popular approximation such as "ansi", "vt100", or "xterm" rather than
+ an exact fit to their capabilities. Not infrequently, an application
+ will have problems with that approach; for example, a key stroke may
+ not operate correctly, or produce no effect but seeming garbage
+ characters on the screen.
+
+ Setting <EM>TERM</EM> has no effect on hardware operation; it affects the way
+ applications communicate with the terminal. Likewise, as a general
+ rule (<STRONG>xterm(1)</STRONG> being a rare exception), terminal emulators that allow
+ you to specify <EM>TERM</EM> as a parameter or configuration value do not change
+ their behavior to match that setting.
</PRE><H3><a name="h3-TERMCAP"><EM>TERMCAP</EM></a></H3><PRE>
- If the <EM>ncurses</EM> library has been configured with <EM>termcap</EM> support,
- <EM>ncurses</EM> will check for a terminal's description in termcap form if it
- is not available in the terminfo database.
-
- The <EM>TERMCAP</EM> environment variable contains either a terminal description
- (with newlines stripped out), or a file name telling where the
- information denoted by the <EM>TERM</EM> environment variable exists. In either
- case, setting it directs <EM>ncurses</EM> to ignore the usual place for this
- information, e.g., /etc/termcap.
+ If <EM>ncurses</EM> is configured with <EM>termcap</EM> support, it checks for a terminal
+ type description in <EM>termcap</EM> format if one in <EM>terminfo</EM> format is not
+ available. Setting this variable directs <EM>ncurses</EM> to ignore the usual
+ <EM>termcap</EM> database location, <EM>/etc/termcap</EM>; see <EM>TERMPATH</EM> below. <EM>TERMCAP</EM>
+ should contain either a terminal description (with newlines stripped
+ out), or a file name indicating where the information required by the
+ <EM>TERM</EM> environment variable is stored.
</PRE><H3><a name="h3-TERMINFO"><EM>TERMINFO</EM></a></H3><PRE>
- <EM>ncurses</EM> can be configured to read from multiple terminal databases.
- The <EM>TERMINFO</EM> variable overrides the location for the default terminal
- database. Terminal descriptions (in terminal format) are stored in
- terminal databases:
-
- <STRONG>o</STRONG> 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 <EM>TERMINFO</EM> variable is used by <EM>curses</EM> applications on those
- systems to override the default location of the terminal database.
-
- <STRONG>o</STRONG> If <EM>ncurses</EM> is built to use hashed databases, then each entry in
- this list may be the path of a hashed database file, e.g.,
+ <EM>ncurses</EM> can be configured to read terminal type description databases
+ in various locations using different formats. This variable overrides
+ the default location.
- /usr/share/terminfo.db
+ <STRONG>o</STRONG> Descriptions in <EM>terminfo</EM> format are normally stored in a directory
+ tree using subdirectories named by the common first letters of the
+ terminal types named therein. This is the scheme used in System V.
- rather than
+ <STRONG>o</STRONG> If <EM>ncurses</EM> is configured to use hashed databases, then <EM>TERMINFO</EM> may
+ name its location, such as <EM>/usr/share/terminfo.db</EM>, rather than
+ <EM>/usr/share/terminfo/</EM>.
- /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, and read it directly rather than using the <EM>terminfo</EM>
+ API.
- 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.
+ <STRONG>o</STRONG> If <EM>ncurses</EM> is configured with <EM>termcap</EM> support, this variable may
+ contain the location of a <EM>termcap</EM> file.
- <STRONG>o</STRONG> If <EM>ncurses</EM> is built with a support for reading termcap files
- directly, then an entry in this list may be the path of a termcap
- file.
+ <STRONG>o</STRONG> If the value of <EM>TERMINFO</EM> begins with "hex:" or "b64:", <EM>ncurses</EM> uses
+ the remainder of the value as a compiled <EM>terminfo</EM> description. You
+ might produce the base64 format using <STRONG><A HREF="infocmp.1m.html">infocmp(1m)</A></STRONG>.
- <STRONG>o</STRONG> If the <EM>TERMINFO</EM> variable begins with "hex:" or "b64:", <EM>ncurses</EM> uses
- the remainder of that variable as a compiled terminal description.
- You might produce the base64 format using <STRONG><A HREF="infocmp.1m.html">infocmp(1m)</A></STRONG>:
+ TERMINFO=$(infocmp -0 -Q2 -q)
+ export TERMINFO
- TERMINFO="$(infocmp -0 -Q2 -q)"
- export TERMINFO
+ The compiled description is used only if it corresponds to the
+ terminal type identified by <EM>TERM</EM>.
- The compiled description is used if it corresponds to the terminal
- identified by the <EM>TERM</EM> variable.
+ Setting <EM>TERMINFO</EM> is the simplest, but not the only, way to direct
+ <EM>ncurses</EM> to a terminal database. The search path is as follows.
- Setting <EM>TERMINFO</EM> is the simplest, but not the only way to set location
- of the default terminal database. The complete list of database
- locations in order follows:
+ <STRONG>o</STRONG> the last terminal database to which the running <EM>ncurses</EM> application
+ wrote, if any
- <STRONG>o</STRONG> the last terminal database to which <EM>ncurses</EM> wrote, if any, is
- searched first
+ <STRONG>o</STRONG> the location specified by the <EM>TERMINFO</EM> environment variable
- <STRONG>o</STRONG> the location specified by the <EM>TERMINFO</EM> environment variable
+ <STRONG>o</STRONG> <EM>$HOME/.terminfo</EM>
- <STRONG>o</STRONG> $HOME/.terminfo
+ <STRONG>o</STRONG> locations listed in the <EM>TERMINFO</EM><STRONG>_</STRONG><EM>DIRS</EM> environment variable
- <STRONG>o</STRONG> locations listed in the <EM>TERMINFO</EM><STRONG>_</STRONG><EM>DIRS</EM> environment variable
+ <STRONG>o</STRONG> location(s) configured and compiled into <EM>ncurses</EM>
- <STRONG>o</STRONG> one or more locations whose names are configured and compiled
- into the <EM>ncurses</EM> library, i.e.,
-
- <STRONG>o</STRONG> /usr/share/terminfo (corresponding to the <EM>TERMINFO</EM><STRONG>_</STRONG><EM>DIRS</EM>
- variable)
-
- <STRONG>o</STRONG> /usr/share/terminfo (corresponding to the <EM>TERMINFO</EM> variable)
+ <STRONG>o</STRONG> <EM>/usr/share/terminfo</EM>
</PRE><H3><a name="h3-TERMINFO_DIRS"><EM>TERMINFO_DIRS</EM></a></H3><PRE>
- 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 <EM>TERMINFO</EM> 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
- extension developed for <EM>ncurses</EM>.
+ This variable specifies a list of locations, akin to <EM>PATH</EM>, in which
+ <EM>ncurses</EM> searches for the terminal type descriptions described by
+ <EM>TERMINFO</EM> above. The list items are separated by colons on Unix and
+ semicolons on OS/2 EMX. System V <EM>terminfo</EM> lacks a corresponding
+ feature; <EM>TERMINFO</EM><STRONG>_</STRONG><EM>DIRS</EM> is an <EM>ncurses</EM> extension.
</PRE><H3><a name="h3-TERMPATH"><EM>TERMPATH</EM></a></H3><PRE>
- If <EM>TERMCAP</EM> does not hold a file name then <EM>ncurses</EM> checks the <EM>TERMPATH</EM>
- environment variable. This is a list of filenames separated by spaces
- or colons (i.e., ":") on Unix, semicolons on OS/2 EMX.
-
- If the <EM>TERMPATH</EM> environment variable is not set, <EM>ncurses</EM> looks in the
- files
-
- /etc/termcap, /usr/share/misc/termcap and $HOME/.termcap,
+ If <EM>TERMCAP</EM> does not hold a terminal type description or file name, then
+ <EM>ncurses</EM> checks the contents of <EM>TERMPATH</EM>, a list of locations, akin to
+ <EM>PATH</EM>, in which it searches for <EM>termcap</EM> terminal type descriptions. The
+ list items are separated by colons on Unix and semicolons on OS/2 EMX.
- 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 $HOME.
+ If both <EM>TERMCAP</EM> and <EM>TERMPATH</EM> are unset or invalid, <EM>ncurses</EM> searches for
+ the files <EM>/etc/termcap</EM>, <EM>/usr/share/misc/termcap</EM>, and <EM>$HOME/.termcap</EM>, in
+ that order.
</PRE><H2><a name="h2-ALTERNATE-CONFIGURATIONS">ALTERNATE CONFIGURATIONS</a></H2><PRE>
Many different <EM>ncurses</EM> configurations are possible, determined by the
options given to the <EM>configure</EM> script when building the library. Run
the script with the <STRONG>--help</STRONG> option to peruse them all. A few are of
- particular significance to the application developer employing <EM>ncurses.</EM>
+ particular significance to the application developer employing <EM>ncurses</EM>.
- --disable-overwrite
+ <STRONG>--disable-overwrite</STRONG>
The standard include for <EM>ncurses</EM> is as noted in <STRONG>SYNOPSIS</STRONG>:
<STRONG>#include</STRONG> <STRONG><curses.h></STRONG>
It also omits a symbolic link which would allow you to use
<STRONG>-lcurses</STRONG> to build executables.
- --enable-widec
+ <STRONG>--enable-widec</STRONG>
The configure script renames the library and (if the
<STRONG>--disable-overwrite</STRONG> option is used) puts the header files in a
different subdirectory. All of the library names have a "w"
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:
+ these features has changed since X/Open Curses, Issue 4:
<STRONG>o</STRONG> Originally, the wide-character feature required the symbol
<STRONG>_XOPEN_SOURCE_EXTENDED</STRONG> but that was only valid for XPG4
applications to be built using either library from the same set of
headers.
- --with-pthread
+ <STRONG>--with-pthread</STRONG>
The configure script renames the library. All of the library
names have a "t" appended to them (before any "w" added by
<STRONG>--enable-widec</STRONG>).
to set these values. Some applications (very few) may require
changes to work with this convention.
- --with-shared
-
- --with-normal
-
- --with-debug
-
- --with-profile
+ <STRONG>--with-shared</STRONG>
+ <STRONG>--with-normal</STRONG>
+ <STRONG>--with-debug</STRONG>
+ <STRONG>--with-profile</STRONG>
The shared and normal (static) library names differ by their
suffixes, e.g., <STRONG>libncurses.so</STRONG> and <STRONG>libncurses.a</STRONG>. The debug and
profiling libraries add a "_g" and a "_p" to the root names
respectively, e.g., <STRONG>libncurses_g.a</STRONG> and <STRONG>libncurses_p.a</STRONG>.
- --with-termlib
+ <STRONG>--with-termlib</STRONG>
Low-level functions which do not depend upon whether the library
supports wide-characters, are provided in the tinfo library.
Those functions are described in these pages:
- <STRONG>o</STRONG> <STRONG><A HREF="curs_extend.3x.html">curs_extend(3x)</A></STRONG> - miscellaneous curses extensions
+ <STRONG>o</STRONG> <STRONG><A HREF="curs_extend.3x.html">curs_extend(3x)</A></STRONG> - miscellaneous <EM>curses</EM> extensions
- <STRONG>o</STRONG> <STRONG><A HREF="curs_inopts.3x.html">curs_inopts(3x)</A></STRONG> - <STRONG>curses</STRONG> input options
+ <STRONG>o</STRONG> <STRONG><A HREF="curs_inopts.3x.html">curs_inopts(3x)</A></STRONG> - <EM>curses</EM> input options
- <STRONG>o</STRONG> <STRONG><A HREF="curs_kernel.3x.html">curs_kernel(3x)</A></STRONG> - low-level <STRONG>curses</STRONG> routines
+ <STRONG>o</STRONG> <STRONG><A HREF="curs_kernel.3x.html">curs_kernel(3x)</A></STRONG> - low-level <EM>curses</EM> routines
- <STRONG>o</STRONG> <STRONG><A HREF="curs_termattrs.3x.html">curs_termattrs(3x)</A></STRONG> - <STRONG>curses</STRONG> environment query routines
+ <STRONG>o</STRONG> <STRONG><A HREF="curs_termattrs.3x.html">curs_termattrs(3x)</A></STRONG> - <EM>curses</EM> environment query routines
- <STRONG>o</STRONG> <STRONG><A HREF="curs_termcap.3x.html">curs_termcap(3x)</A></STRONG> - <STRONG>curses</STRONG> emulation of termcap
+ <STRONG>o</STRONG> <STRONG><A HREF="curs_termcap.3x.html">curs_termcap(3x)</A></STRONG> - <EM>curses</EM> emulation of <EM>termcap</EM>
- <STRONG>o</STRONG> <STRONG><A HREF="curs_terminfo.3x.html">curs_terminfo(3x)</A></STRONG> - <STRONG>curses</STRONG> interfaces to terminfo database
+ <STRONG>o</STRONG> <STRONG><A HREF="curs_terminfo.3x.html">curs_terminfo(3x)</A></STRONG> - <EM>curses</EM> interface to <EM>terminfo</EM> database
- <STRONG>o</STRONG> <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG> - miscellaneous <STRONG>curses</STRONG> utility routines
+ <STRONG>o</STRONG> <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG> - miscellaneous <EM>curses</EM> utility routines
- --with-trace
+ <STRONG>--with-trace</STRONG>
The <STRONG>trace</STRONG> 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
</PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE>
- If standard output from a <EM>ncurses</EM> 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.
+ X/Open Curses permits most functions it specifies to be made available
+ as macros as well. <EM>ncurses</EM> does so
- See subsection "Header files" below regarding symbols exposed by
+ <STRONG>o</STRONG> for functions that return values via their parameters,
+
+ <STRONG>o</STRONG> to support obsolete features,
+
+ <STRONG>o</STRONG> to reuse functions (for example, those that move the cursor before
+ another operation), and
+
+ <STRONG>o</STRONG> a few special cases.
+
+ If the standard output file descriptor of an <EM>ncurses</EM> program is
+ redirected to something that is not a terminal device, the library
+ writes screen updates to the standard error file descriptor. This was
+ an undocumented feature of SVr3 <EM>curses</EM>.
+
+ See subsection "Header Files" below regarding symbols exposed by
inclusion of <EM>curses.h</EM>.
</PRE><H2><a name="h2-EXTENSIONS">EXTENSIONS</a></H2><PRE>
- The <EM>ncurses</EM> library can be compiled with an option (<STRONG>-DUSE_GETCAP</STRONG>) that
- falls back to the old-style /etc/termcap file if the terminal setup
- code cannot find a terminfo entry corresponding to <EM>TERM</EM>. Use of this
- feature is not recommended, as it essentially includes an entire
- termcap compiler in the <EM>ncurses</EM> startup code, at significant cost in
- core and startup cycles.
-
- The <EM>ncurses</EM> library includes facilities for capturing mouse events on
- certain terminals (including xterm). See the <STRONG><A HREF="curs_mouse.3x.html">curs_mouse(3x)</A></STRONG> manual
- page for details.
-
- The <EM>ncurses</EM> library includes facilities for responding to window
- resizing events, e.g., when running in an xterm. See the
- <STRONG><A HREF="resizeterm.3x.html">resizeterm(3x)</A></STRONG> and <STRONG><A HREF="wresize.3x.html">wresize(3x)</A></STRONG> manual pages for details. In addition,
- the library may be configured with a <STRONG>SIGWINCH</STRONG> handler.
-
- The <EM>ncurses</EM> 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 <STRONG><A HREF="define_key.3x.html">define_key(3x)</A></STRONG> <STRONG><A HREF="key_defined.3x.html">key_defined(3x)</A></STRONG>, and
- <STRONG><A HREF="keyok.3x.html">keyok(3x)</A></STRONG> manual pages for details.
-
- The <EM>ncurses</EM> 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
- <STRONG><A HREF="default_colors.3x.html">default_colors(3x)</A></STRONG> manual page for details.
-
- The <EM>ncurses</EM> library includes a function for directing application
- output to a printer attached to the terminal device. See the
- <STRONG><A HREF="curs_print.3x.html">curs_print(3x)</A></STRONG> manual page for details.
+ <EM>ncurses</EM> enables an application to capture mouse events on certain
+ terminals, including <STRONG>xterm(1)</STRONG>; see <STRONG><A HREF="curs_mouse.3x.html">curs_mouse(3x)</A></STRONG>.
+ <EM>ncurses</EM> provides a means of responding to window resizing events, as
+ when running in a GUI terminal emulator application such as <EM>xterm</EM>; see
+ <STRONG><A HREF="resizeterm.3x.html">resizeterm(3x)</A></STRONG> and <STRONG><A HREF="wresize.3x.html">wresize(3x)</A></STRONG>.
-</PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
- The <EM>ncurses</EM> library is intended to be BASE-level conformant with XSI
- Curses. The EXTENDED XSI Curses functionality (including color
- support) is supported.
+ <EM>ncurses</EM> allows an application to query the terminal for the presence of
+ a wide variety of special keys; see <STRONG><A HREF="curs_getch.3x.html">has_key(3x)</A></STRONG>.
- A small number of local differences (that is, individual differences
- between the XSI Curses and <EM>ncurses</EM> calls) are described in <STRONG>PORTABILITY</STRONG>
- sections of the library man pages.
+ <EM>ncurses</EM> extends the fixed set of function key capabilities specified by
+ X/Open Curses by allowing the application programmer to define
+ additional key events at runtime; see <STRONG><A HREF="define_key.3x.html">define_key(3x)</A></STRONG>, <STRONG><A HREF="key_defined.3x.html">key_defined(3x)</A></STRONG>,
+ <STRONG><A HREF="keybound.3x.html">keybound(3x)</A></STRONG>, and <STRONG><A HREF="keyok.3x.html">keyok(3x)</A></STRONG>.
+ <EM>ncurses</EM> can exploit the capabilities of terminals implementing
+ ISO 6429/ECMA-48 SGR 39 and SGR 49 sequences, which allow an
+ application to reset the terminal to its original foreground and
+ background colors. From a user's perspective, the application is able
+ to draw colored text on a background whose color is set independently,
+ providing better control over color contrasts. See <STRONG><A HREF="default_colors.3x.html">default_colors(3x)</A></STRONG>.
-</PRE><H3><a name="h3-Error-Checking">Error Checking</a></H3><PRE>
- In many cases, X/Open Curses is vague about error conditions, omitting
- some of the SVr4 documentation.
+ An <EM>ncurses</EM> application can eschew knowledge of <EM>WINDOW</EM> structure
+ internals, instead using accessor functions such as <STRONG><A HREF="curs_opaque.3x.html">is_scrollok(3x)</A></STRONG>.
- Unlike other implementations, this one checks parameters such as
- pointers to <EM>WINDOW</EM> 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 application which of several possible errors were detected.
- Relying on this (or some other) extension will adversely affect the
- portability of curses applications.
+ <EM>ncurses</EM> enables an application to direct application output to a
+ printer attached to the terminal device; see <STRONG><A HREF="curs_print.3x.html">curs_print(3x)</A></STRONG>.
+ <EM>ncurses</EM> offers <STRONG><A HREF="curs_slk.3x.html">slk_attr(3x)</A></STRONG> as a counterpart of <STRONG><A HREF="curs_attr.3x.html">attr_get(3x)</A></STRONG> for soft-
+ label key lines, and <STRONG><A HREF="curs_slk.3x.html">extended_slk_color(3x)</A></STRONG> as a form of <STRONG><A HREF="curs_slk.3x.html">slk_color(3x)</A></STRONG>
+ that can gather color information from them when many colors are
+ supported.
-</PRE><H3><a name="h3-Extensions-Versus-Portability">Extensions Versus Portability</a></H3><PRE>
- Most of the extensions provided by <EM>ncurses</EM> have not been standardized.
- Some have been incorporated into other implementations, such as
- PDCurses or NetBSD curses. Here are a few to consider:
+ Some extensions are available only if <EM>ncurses</EM> permits modification of
+ <STRONG><A HREF="unctrl.3x.html">unctrl(3x)</A></STRONG>'s behavior; see <STRONG><A HREF="legacy_coding.3x.html">use_legacy_coding(3x)</A></STRONG>. <EM>ncurses</EM> is compiled
+ to support them; section "ALTERNATE CONFIGURATIONS" describes how.
- <STRONG>o</STRONG> The routine <STRONG>has_key</STRONG> is not part of XPG4, nor is it present in SVr4.
- See the <STRONG><A HREF="curs_getch.3x.html">curs_getch(3x)</A></STRONG> manual page for details.
+ <STRONG>o</STRONG> Rudimentary support for multi-threaded applications may be
+ available; see <STRONG><A HREF="curs_threads.3x.html">curs_threads(3x)</A></STRONG>.
- <STRONG>o</STRONG> The routine <STRONG>slk_attr</STRONG> is not part of XPG4, nor is it present in
- SVr4. See the <STRONG><A HREF="curs_slk.3x.html">curs_slk(3x)</A></STRONG> manual page for details.
+ <STRONG>o</STRONG> Functions that ease the management of multiple screens can be
+ exposed; see <STRONG><A HREF="curs_sp_funcs.3x.html">curs_sp_funcs(3x)</A></STRONG>.
- <STRONG>o</STRONG> The routines <STRONG>getmouse</STRONG>, <STRONG>mousemask</STRONG>, <STRONG>ungetmouse</STRONG>, <STRONG>mouseinterval</STRONG>, and
- <STRONG>wenclose</STRONG> relating to mouse interfacing are not part of XPG4, nor
- are they present in SVr4. See the <STRONG><A HREF="curs_mouse.3x.html">curs_mouse(3x)</A></STRONG> manual page for
- details.
+ <STRONG>o</STRONG> To aid applications to debug their memory usage, <EM>ncurses</EM> optionally
+ offers functions to more aggressively free memory it dynamically
+ allocates itself; see <STRONG><A HREF="curs_memleaks.3x.html">curs_memleaks(3x)</A></STRONG>.
- <STRONG>o</STRONG> The routine <STRONG>mcprint</STRONG> was not present in any previous curses
- implementation. See the <STRONG><A HREF="curs_print.3x.html">curs_print(3x)</A></STRONG> manual page for details.
+ <STRONG>o</STRONG> The library facilitates auditing and troubleshooting of its
+ behavior; see <STRONG><A HREF="curs_trace.3x.html">curs_trace(3x)</A></STRONG>.
- <STRONG>o</STRONG> The routine <STRONG>wresize</STRONG> is not part of XPG4, nor is it present in SVr4.
- See the <STRONG><A HREF="wresize.3x.html">wresize(3x)</A></STRONG> manual page for details.
+ <STRONG>o</STRONG> The compiler option <STRONG>-DUSE_GETCAP</STRONG> causes the library to fall back to
+ reading <EM>/etc/termcap</EM> if the terminal setup code cannot find a <EM>term-</EM>
+ <EM>info</EM> entry corresponding to <EM>TERM</EM>. Use of this feature is not
+ recommended, as it essentially includes an entire <EM>termcap</EM> compiler
+ in the <EM>ncurses</EM> startup code, at a cost in memory usage and
+ application launch latency.
- <STRONG>o</STRONG> The <EM>WINDOW</EM> structure's internal details can be hidden from
- application programs. See <STRONG><A HREF="curs_opaque.3x.html">curs_opaque(3x)</A></STRONG> for the discussion of
- <STRONG>is_scrollok</STRONG>, etc.
+ <EM>PDCurses</EM> and NetBSD <EM>curses</EM> incorporate some <EM>ncurses</EM> extensions.
+ Individual man pages indicate where this is the case.
- <STRONG>o</STRONG> This implementation can be configured to provide rudimentary
- support for multi-threaded applications. See <STRONG><A HREF="curs_threads.3x.html">curs_threads(3x)</A></STRONG> for
- details.
- <STRONG>o</STRONG> This implementation can also be configured to provide a set of
- functions which improve the ability to manage multiple screens.
- See <STRONG><A HREF="curs_sp_funcs.3x.html">curs_sp_funcs(3x)</A></STRONG> for details.
+</PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
+ X/Open Curses defines two levels of conformance, "base" and "enhanced".
+ The latter includes several additional features, such as wide-character
+ and color support. <EM>ncurses</EM> intends base-level conformance with X/Open
+ Curses, and supports nearly all features of its enhanced level.
+
+ Differences between X/Open Curses and <EM>ncurses</EM> are documented in the
+ "PORTABILITY" sections of applicable man pages.
+
+
+</PRE><H3><a name="h3-Error-Checking">Error Checking</a></H3><PRE>
+ In many cases, X/Open Curses is vague about error conditions, omitting
+ some of the SVr4 documentation.
+
+ Unlike other implementations, <EM>ncurses</EM> checks pointer parameters, such
+ as those to <EM>WINDOW</EM> structures, to ensure that they are not null. This
+ is done primarily to guard against programmer error. The standard
+ interface does not provide a way for the library to tell an application
+ which of several possible errors occurred. Relying on this (or some
+ other) extension adversely affects the portability of <EM>curses</EM>
+ applications.
</PRE><H3><a name="h3-Padding-Differences">Padding Differences</a></H3><PRE>
- In historic curses versions, delays embedded in the capabilities <STRONG>cr</STRONG>,
- <STRONG>ind</STRONG>, <STRONG>cub1</STRONG>, <STRONG>ff</STRONG> and <STRONG>tab</STRONG> activated corresponding delay bits in the Unix
- tty driver. In this implementation, all padding is done by sending NUL
- bytes. This method is slightly more expensive, but narrows the
- interface to the Unix kernel significantly and increases the package's
- portability correspondingly.
+ In historical <EM>curses</EM> implementations, delays embedded in the <EM>terminfo</EM>
+ capabilities <STRONG>carriage_return</STRONG> (<STRONG>cr</STRONG>), <STRONG>scroll_forward</STRONG> (<STRONG>ind</STRONG>), <STRONG>cursor_left</STRONG>
+ (<STRONG>cub1</STRONG>), <STRONG>form_feed</STRONG> (<STRONG>ff</STRONG>), and <STRONG>tab</STRONG> (<STRONG>ht</STRONG>) activated corresponding delay bits
+ in the Unix terminal driver. <EM>ncurses</EM> performs all padding by sending
+ NUL bytes to the device. This method is slightly more expensive, but
+ narrows the interface to the Unix kernel significantly and
+ correspondingly increases the package's portability.
</PRE><H3><a name="h3-Header-Files">Header Files</a></H3><PRE>
The header file <EM>curses.h</EM> itself includes the header files <EM>stdio.h</EM> and
<EM>unctrl.h</EM>.
- X/Open Curses has more to say, but does not finish the story:
+ X/Open Curses has more to say,
- The inclusion of <curses.h> may make visible all symbols from the
- headers <stdio.h>, <term.h>, <termios.h>, and <wchar.h>.
+ The inclusion of <EM>curses.h</EM> may make visible all symbols from the
+ headers <EM>stdio.h</EM>, <EM>term.h</EM>, <EM>termios.h</EM>, and <EM>wchar.h</EM>.
- Here is a more complete story:
+ but does not finish the story. A more complete account follows.
- <STRONG>o</STRONG> Starting with BSD curses, all implementations have included
- <stdio.h>.
+ <STRONG>o</STRONG> Starting with 4BSD <EM>curses</EM> (1980) all implementations have provided
+ a <EM>curses.h</EM> file.
- BSD curses included <curses.h> and <unctrl.h> from an internal
- header file <EM>curses.ext</EM> ("ext" abbreviated "externs").
+ BSD <EM>curses</EM> code included <EM>curses.h</EM> and <EM>unctrl.h</EM> from an internal
+ header file <EM>curses.ext</EM>, where "ext" abbreviated "externs".
- BSD curses used <stdio.h> internally (for <STRONG>printw</STRONG> and <STRONG>scanw</STRONG>), but
- nothing in <curses.h> itself relied upon <stdio.h>.
+ The implementations of <EM>printw</EM> and <EM>scanw</EM> used undocumented internal
+ functions of the standard I/O library (<STRONG>_</STRONG><EM>doprnt</EM> and <STRONG>_</STRONG><EM>doscan</EM>), but
+ nothing in <EM>curses.h</EM> itself relied upon <EM>stdio.h</EM>.
- <STRONG>o</STRONG> SVr2 curses added <STRONG><A HREF="curs_initscr.3x.html">newterm(3x)</A></STRONG>, which relies upon <stdio.h>. That
- is, the function prototype uses <STRONG>FILE</STRONG>.
+ <STRONG>o</STRONG> SVr2 <EM>curses</EM> added <EM>newterm</EM>, which relies upon <EM>stdio.h</EM> because its
+ function prototype employs the <EM>FILE</EM> type.
- SVr4 curses added <STRONG>putwin</STRONG> and <STRONG>getwin</STRONG>, which also use <stdio.h>.
+ SVr4 <EM>curses</EM> added <EM>putwin</EM> and <EM>getwin</EM>, which also use <EM>stdio.h</EM>.
- X/Open Curses documents all three of these functions.
+ X/Open Curses specifies all three of these functions.
- SVr4 curses and X/Open Curses do not require the developer to
- include <stdio.h> before including <curses.h>. Both document
- curses showing <curses.h> as the only required header.
+ SVr4 <EM>curses</EM> and X/Open Curses do not require the developer to
+ include <EM>stdio.h</EM> before <EM>curses.h</EM>. Both document use of <EM>curses</EM> as
+ requiring only <EM>curses.h</EM>.
- As a result, standard <curses.h> will always include <stdio.h>.
+ As a result, standard <EM>curses.h</EM> always includes <EM>stdio.h</EM>.
- <STRONG>o</STRONG> X/Open Curses is inconsistent with respect to SVr4 regarding
- <unctrl.h>.
+ <STRONG>o</STRONG> X/Open Curses and SVr4 <EM>curses</EM> are inconsistent with respect to
+ <EM>unctrl.h</EM>.
- As noted in <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>, <EM>ncurses</EM> includes <unctrl.h> from
- <curses.h> (like SVr4).
+ As noted in <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>, <EM>ncurses</EM> includes <EM>unctrl.h</EM> from <EM>curses.h</EM>
+ (as SVr4 does).
- <STRONG>o</STRONG> X/Open's comments about <term.h> and <termios.h> may refer to HP-UX
- and AIX:
+ <STRONG>o</STRONG> X/Open Curses's comments about <EM>term.h</EM> and <EM>termios.h</EM> may refer to
+ HP-UX and AIX.
- HP-UX curses includes <term.h> from <curses.h> to declare <STRONG>setupterm</STRONG>
- in curses.h, but <EM>ncurses</EM> (and Solaris curses) do not.
+ HP-UX <EM>curses</EM> includes <EM>term.h</EM> from <EM>curses.h</EM> to declare <EM>setupterm</EM> in
+ <EM>curses.h</EM>, but <EM>ncurses</EM> and Solaris <EM>curses</EM> do not.
- AIX curses includes <term.h> and <termios.h>. Again, <EM>ncurses</EM> (and
- Solaris curses) do not.
+ AIX <EM>curses</EM> includes <EM>term.h</EM> and termios.h<EM>.</EM> Again, <EM>ncurses</EM> and
+ Solaris <EM>curses</EM> do not.
- <STRONG>o</STRONG> X/Open says that <curses.h> <EM>may</EM> include <term.h>, but there is no
- requirement that it do that.
+ <STRONG>o</STRONG> X/Open Curses says that <EM>curses.h</EM> <STRONG>may</STRONG> include <EM>term.h</EM>, but does not
+ require it to do so.
- Some programs use functions declared in both <curses.h> and
- <term.h>, and must include both headers in the same module. Very
- old versions of AIX curses required including <curses.h> before
- including <term.h>.
+ Some programs use functions declared in both <EM>curses.h</EM> and <EM>term.h</EM>,
+ and must include both header files in the same module. Very old
+ versions of AIX <EM>curses</EM> required inclusion of <EM>curses.h</EM> before
+ <EM>term.h</EM>.
- Because <EM>ncurses</EM> header files include the headers needed to define
- datatypes used in the headers, <EM>ncurses</EM> header files can be included
- in any order. But for portability, you should include <curses.h>
- before <term.h>.
+ The header files supplied by <EM>ncurses</EM> include the standard library
+ headers required for its declarations, so <EM>ncurses</EM>'s own header
+ files can be included in any order. But for portability, you
+ should include <EM>curses.h</EM> before <EM>term.h</EM>.
- <STRONG>o</STRONG> X/Open Curses says <EM>"may</EM> <EM>make</EM> <EM>visible"</EM> because including a header
- file does not necessarily make all symbols in it visible (there are
- ifdef's to consider).
+ <STRONG>o</STRONG> X/Open Curses says "may make visible" because including a header
+ file does not necessarily make visible all of the symbols in it
+ (consider <STRONG>#ifdef</STRONG> and similar).
- For instance, in <EM>ncurses</EM> <wchar.h> <EM>may</EM> be included if the proper
- symbol is defined, and if <EM>ncurses</EM> is configured for wide-character
- support. If the header is included, its symbols may be made
- visible. That depends on the value used for <STRONG>_XOPEN_SOURCE</STRONG> feature
- test macro.
+ For instance, <EM>ncurses</EM>'s <EM>curses.h</EM> <STRONG>may</STRONG> include <EM>wchar.h</EM> if the proper
+ symbol is defined, and if <EM>ncurses</EM> is configured for wide-character
+ support. If <EM>wchar.h</EM> is included, its symbols <STRONG>may</STRONG> be made visible
+ depending on the value of the <STRONG>_XOPEN_SOURCE</STRONG> feature test macro.
- <STRONG>o</STRONG> X/Open Curses documents one required header, in a special case:
- <stdarg.h> before <curses.h> to prototype the <STRONG>vw_printw</STRONG> and
- <STRONG>vw_scanw</STRONG> functions (as well as the obsolete the <STRONG>vwprintw</STRONG> and
- <STRONG>vwscanw</STRONG> functions). Each of those uses a <STRONG>va_list</STRONG> parameter.
+ <STRONG>o</STRONG> X/Open Curses mandates an application's inclusion of one standard C
+ library header in a special case: <EM>stdarg.h</EM> before <EM>curses.h</EM> to
+ prototype the functions <EM>vw</EM><STRONG>_</STRONG><EM>printw</EM> and <EM>vw</EM><STRONG>_</STRONG><EM>scanw</EM> (as well as the
+ obsolete <EM>vwprintw</EM> and <EM>vwscanw</EM>). Each of these takes a variadic
+ argument list, a <EM>va</EM><STRONG>_</STRONG><EM>list</EM> parameter, like that of <STRONG>printf(3)</STRONG>.
- The two obsolete functions were introduced in SVr3. The other
- functions were introduced in X/Open Curses. In between, SVr4
- curses provided for the possibility that an application might
- include either <varargs.h> or <stdarg.h>. Initially, that was done
- by using <STRONG>void*</STRONG> for the <STRONG>va_list</STRONG> parameter. Later, a special type
- (defined in <stdio.h>) was introduced, to allow for compiler type-
- checking. That special type is always available, because <stdio.h>
- is always included by <curses.h>.
+ SVr3 <EM>curses</EM> introduced the two obsolete functions, and X/Open
+ Curses the others. In between, SVr4 <EM>curses</EM> provided for the
+ possibility that an application might include either <EM>varargs.h</EM> or
+ <EM>stdarg.h</EM>. These represented contrasting approaches to handling
+ variadic argument lists. The older interface, <EM>varargs.h</EM>, used a
+ pointer to <EM>char</EM> for variadic functions' <EM>va</EM><STRONG>_</STRONG><EM>list</EM> parameter. Later,
+ the list acquired its own standard data type, <EM>va</EM><STRONG>_</STRONG><EM>list</EM>, defined in
+ <EM>stdarg.h</EM>, empowering the compiler to check the types of a function
+ call's actual parameters against the formal ones declared in its
+ prototype.
- None of the X/Open Curses implementations require an application to
- include <stdarg.h> before <curses.h> because they either have
- allowed for a special type, or (like <EM>ncurses</EM>) include <stdarg.h>
- directly to provide a portable interface.
+ No conforming implementations of X/Open Curses require an
+ application to include <EM>stdarg.h</EM> before <EM>curses.h</EM> because they either
+ have allowed for a special type, or, like <EM>ncurses</EM>, they include
+ <EM>stdarg.h</EM> themselves to provide a portable interface.
</PRE><H2><a name="h2-AUTHORS">AUTHORS</a></H2><PRE>
-ncurses 6.4 202
3-12-23 <STRONG><A HREF="ncurses.3x.html">ncurses(3x)</A></STRONG>
+ncurses 6.4 202
4-04-20 <STRONG><A HREF="ncurses.3x.html">ncurses(3x)</A></STRONG>
</PRE>
<div class="nav">
<ul>
<li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li>
<li><a href="#h2-DESCRIPTION">DESCRIPTION</a>
<ul>
-<li><a href="#h3-Initialization">Initialization</a></li>
+<li><a href="#h3-Application-Structure">Application Structure</a></li>
<li><a href="#h3-Overview">Overview</a></li>
-<li><a href="#h3-Effects-of-GUIs-and-Environment-Variables">Effects of GUIs and Environment Variables</a></li>
+<li><a href="#h3-Initialization">Initialization</a></li>
<li><a href="#h3-Naming-Conventions">Naming Conventions</a></li>
<li><a href="#h3-Wide-and-Non-wide-Character-Configurations">Wide and Non-wide Character Configurations</a></li>
<li><a href="#h3-Function-Name-Index">Function Name Index</a></li>
<li><a href="#h2-RETURN-VALUE">RETURN VALUE</a></li>
<li><a href="#h2-ENVIRONMENT">ENVIRONMENT</a>
<ul>
-<li><a href="#h3-CC-command-character">CC command-character</a></li>
<li><a href="#h3-BAUDRATE">BAUDRATE</a></li>
+<li><a href="#h3-CC-_command-character_">CC (command character)</a></li>
<li><a href="#h3-COLUMNS">COLUMNS</a></li>
<li><a href="#h3-ESCDELAY">ESCDELAY</a></li>
<li><a href="#h3-HOME">HOME</a></li>
<li><a href="#h2-PORTABILITY">PORTABILITY</a>
<ul>
<li><a href="#h3-Error-Checking">Error Checking</a></li>
-<li><a href="#h3-Extensions-Versus-Portability">Extensions Versus Portability</a></li>
<li><a href="#h3-Padding-Differences">Padding Differences</a></li>
<li><a href="#h3-Header-Files">Header Files</a></li>
</ul>
projects / ncurses.git / blobdiff