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-<H1 class="no-header">ncurses 3x 2023-12-17 ncurses 6.4 Library calls</H1>
+<H1 class="no-header">ncurses 3x 2024-01-13 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>
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 20231217).
+ This describes <EM>ncurses</EM> version 6.4 (patch 20240113).
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
<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> "EXTENSIONS" presents <EM>ncurses</EM> innovations beyond the X/Open Curses
- standard and/or the SVr4 <EM>curses</EM> implementation. They are termed
- <EM>extensions</EM> to indicate that they cannot be implemented solely by
+ 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
+ <EM>extensions</EM> to indicate that they cannot be implemented solely by
using the library API, but require access to the library's internal
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 to
multiple implementations.
- <STRONG>o</STRONG> "HISTORY" examines points of detail in <EM>ncurses</EM> and other <EM>curses</EM>
+ <STRONG>o</STRONG> "HISTORY" examines points of detail in <EM>ncurses</EM> and other <EM>curses</EM>
implementations over the decades of their development, particularly
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 also the section on
- <STRONG>ALTERNATE</STRONG> <STRONG>CONFIGURATIONS</STRONG>.
-
- 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
+ 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.
+
+ 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-Initialization">Initialization</a></H3><PRE>
- The library uses the locale which the calling program has initialized.
+ 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>
- 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
+ If the locale is not initialized, the library assumes that characters
+ are printable as in ISO-8859-1, to work with certain legacy programs.
+ You should initialize the locale and not rely on specific details of
the library when the locale has not been setup.
- The function <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
+ 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.
- To get character-at-a-time input without echoing (most interactive,
- screen oriented programs want this), the following sequence should be
+ To get character-at-a-time input without echoing (most interactive,
+ screen oriented programs want this), the following sequence should be
used:
<STRONG>initscr();</STRONG> <STRONG>cbreak();</STRONG> <STRONG>noecho();</STRONG>
<STRONG>keypad(stdscr,</STRONG> <STRONG>TRUE);</STRONG>
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>
+ 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>.
</PRE><H3><a name="h3-Overview">Overview</a></H3><PRE>
- A <EM>curses</EM> library abstracts the terminal screen by representing all or
- part of it as a <EM>WINDOW</EM> data structure. A <EM>window</EM> is a rectangular grid
- of character cells, addressed by row and column coordinates (<EM>y</EM>, <EM>x</EM>),
+ A <EM>curses</EM> library abstracts the terminal screen by representing all or
+ part of it as a <EM>WINDOW</EM> data structure. A <EM>window</EM> is a rectangular grid
+ of character cells, addressed by row and column coordinates (<EM>y</EM>, <EM>x</EM>),
with the upper left corner as (0, 0). A window called <STRONG>stdscr</STRONG>, the same
- size as the terminal screen, is always available. Create others with
+ 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-
+ 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
+ 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.
+ 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
+ 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>
+ 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>
+ 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.
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
+ that are not constrained to the size of the terminal screen and whose
contents need not be completely displayed. See <STRONG><A HREF="curs_pad.3x.html">curs_pad(3x)</A></STRONG>.
- In addition to drawing characters on the screen, rendering attributes
- and colors may be supported, causing the characters to show up in such
- modes as underlined, in reverse video, or in color on terminals that
+ In addition to drawing characters on the screen, rendering attributes
+ and colors may be supported, causing the characters to show up in such
+ modes as underlined, in reverse video, or in color on terminals that
support such display enhancements. See <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG>.
- <EM>curses</EM> predefines symbols for a small set of line graphics characters,
- corresponding to the VT100 line drawing set. 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 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> is implemented using the operating system's terminal driver;
- keystroke events are not received as scan codes but as byte sequences.
- Graphical keycaps (alphanumeric and punctuation keys, and the space)
+ <EM>curses</EM> is implemented using the operating system's terminal driver;
+ keystroke events are received not as scan codes but as byte sequences.
+ Graphical keycaps (alphanumeric and punctuation keys, and the space)
appear as-is. Everything else, including the tab, enter/return,
- keypad, arrow, and function keys, appears as a control character or a
- multibyte <EM>escape</EM> <EM>sequence.</EM> <EM>curses</EM> translates these into unique <EM>key</EM>
+ keypad, arrow, and function keys, appears as a control character or a
+ 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>.
</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.
+ 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.
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
<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
<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
+ data than fits into an integral 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>
+
+ 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
+ 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
- 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.
-
- <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
- functions of ISO C and their constant <STRONG>EOF</STRONG>.
-
- The wide library provides additional functions that
- complement those in the non-wide library where the size of
- the underlying character type is significant. A somewhat
- 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
+ <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, 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
+ functions of ISO C and its constant <STRONG>EOF</STRONG>.
+
+ The wide library provides additional functions that
+ complement those in the non-wide library where the size of
+ the underlying character type is significant. A somewhat
+ 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>.
- This convention is inapplicable to some non-wide function
+ 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,
- "bkgd" becomes "bkgrnd"; the window border-drawing and
+ "bkgd" becomes "bkgrnd"; the window border-drawing and
-clearing functions are suffixed with "_set".
</PRE><H3><a name="h3-Function-Name-Index">Function Name Index</a></H3><PRE>
The following table lists the <EM>curses</EM> functions provided in the non-wide
- and wide APIs and the corresponding man pages that describe them.
- Those flagged with "*" are <EM>ncurses</EM>-specific, neither described by
+ and wide APIs and the corresponding man pages that describe them.
+ Those flagged with "*" are <EM>ncurses</EM>-specific, neither described by
X/Open Curses nor present in SVr4.
<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>
erasechar <STRONG><A HREF="curs_termattrs.3x.html">curs_termattrs(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>*
+ 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>*
insdelln <STRONG><A HREF="curs_deleteln.3x.html">curs_deleteln(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>
+ 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>
mvin_wch <STRONG><A HREF="curs_in_wch.3x.html">curs_in_wch(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>
+ 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>
nl <STRONG><A HREF="curs_inopts.3x.html">curs_inopts(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>
+ 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>
start_color <STRONG><A HREF="curs_color.3x.html">curs_color(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>
+ 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>
wbkgrnd <STRONG><A HREF="curs_bkgrnd.3x.html">curs_bkgrnd(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>
+ 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>
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
+ 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
</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.
+ 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.
- Routines that return pointers return <STRONG>NULL</STRONG> on error.
+ Functions with a "mv" prefix first perform cursor movement using <STRONG>wmove</STRONG>
+ and fail if the position is outside the window, or (for "mvw"
+ functions) if the <EM>WINDOW</EM> pointer is null.
</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
+ 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.
-</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-CC-
_command-character_"><EM>CC</EM> (command character)</a></H3><PRE>
+ When set, change the <STRONG>command_character</STRONG> (<STRONG>cmdch</STRONG>) capability value of
+ loaded <EM>terminfo</EM> entries to the value of this variable. Very few <EM>term-</EM>
+ <EM>info</EM> entries provide this feature.
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
</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
+ 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.
</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
+ 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
+ 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
+ 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
+ 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
+ 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.
</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
+ a character sequence, e.g., a function key. The default value, 1000
+ milliseconds, is enough for most uses. However, it is made a variable
to accommodate unusual applications.
- The most common instance where you may wish to change this value is to
- work with slow hosts, e.g., running on a network. If the host cannot
- read characters rapidly enough, it will have the same effect as if the
- terminal did not send characters rapidly enough. The library will
+ The most common instance where you may wish to change this value is to
+ work with slow hosts, e.g., running on a network. If the host cannot
+ read characters rapidly enough, it will have the same effect as if the
+ terminal did not send characters rapidly enough. The library will
still see a timeout.
- Note that xterm mouse events are built up from character sequences
- received from the xterm. If your application makes heavy use of
- multiple-clicking, you may wish to lengthen this default value because
- the timeout applies to the composed multi-click event as well as the
+ Note that xterm mouse events are built up from character sequences
+ received from the xterm. If your application makes heavy use of
+ multiple-clicking, you may wish to lengthen this default value because
+ the timeout applies to the composed multi-click event as well as the
individual clicks.
In addition to the environment variable, this implementation provides a
- global variable with the same name. Portable applications should not
- rely upon the presence of <STRONG>ESCDELAY</STRONG> in either form, but setting the
- environment variable rather than the global variable does not create
+ global variable with the same name. Portable applications should not
+ rely upon the presence of <STRONG>ESCDELAY</STRONG> in either form, but setting the
+ environment variable rather than the global variable does not create
problems when compiling an application.
</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
+ Tells <EM>ncurses</EM> where your home directory is. That is where it may read
and write auxiliary terminal descriptions:
$HOME/.termcap
</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
+ Like <EM>COLUMNS</EM>, specify the height of the screen in characters. See
<EM>COLUMNS</EM> for a detailed description.
</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
+ 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
3 = middle.
This variable lets you customize the mouse. The variable must be three
- numeric digits 1-3 in any order, e.g., 123 or 321. If it is not
+ numeric digits 1-3 in any order, e.g., 123 or 321. If it is not
specified, <EM>ncurses</EM> uses 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
+ 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.
</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
+ 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
+ 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_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
+ 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
</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
+ <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.
</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
+ 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.
</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
+ Most of the terminal descriptions in the terminfo database are written
+ for real "hardware" terminals. Many people use terminal emulators
which run in a windowing environment and use curses-based applications.
- Terminal emulators can duplicate all of the important aspects of a
- hardware terminal, but they do not have the same limitations. The
- chief limitation of a hardware terminal from the standpoint of your
- application is the management of dataflow, i.e., timing. Unless a
- hardware terminal is interfaced into a terminal concentrator (which
- does flow control), it (or your application) must manage dataflow,
- preventing overruns. The cheapest solution (no hardware cost) is for
- your program to do this by pausing after operations that the terminal
+ Terminal emulators can duplicate all of the important aspects of a
+ hardware terminal, but they do not have the same limitations. The
+ chief limitation of a hardware terminal from the standpoint of your
+ application is the management of dataflow, i.e., timing. Unless a
+ hardware terminal is interfaced into a terminal concentrator (which
+ does flow control), it (or your application) must manage dataflow,
+ preventing overruns. The cheapest solution (no hardware cost) is for
+ your program to do this by pausing after operations that the terminal
does slowly, such as clearing the display.
- As a result, many terminal descriptions (including the vt100) have
- delay times embedded. You may wish to use these descriptions, but not
+ As a result, many terminal descriptions (including the vt100) have
+ delay times embedded. You may wish to use these descriptions, but not
want to pay the performance penalty.
- Set the <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
+ 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>.
<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)
+ <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
+ 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 stdio 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>
+ 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.
</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
+ 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>
+ 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>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
+ 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
+ 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
# linux console, if patched to provide working
xterm-utf8|xterm relying on UTF-8 line-graphics,
U8#1, use=xterm,
- The name "U8" is chosen to be two characters, to permit it to be used
+ The name "U8" is chosen to be two characters, to permit it to be used
by applications that use <EM>ncurses</EM>' termcap 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
+ 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
+ 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.
</PRE><H3><a name="h3-TERM"><EM>TERM</EM></a></H3><PRE>
- Denotes your terminal type. Each terminal type is distinct, though
+ 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
+ <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
+ 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.
</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
+ 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
+ (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
+ case, setting it directs <EM>ncurses</EM> to ignore the usual place for this
information, e.g., /etc/termcap.
</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
+ <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
+ 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
+ <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.,
/usr/share/terminfo.db
/usr/share/terminfo/
- The hashed database uses less disk-space and is a little faster
- than the directory tree. However, some applications assume the
- existence of the directory tree, reading it directly rather than
+ The hashed database uses less disk-space and is a little faster
+ than the directory tree. However, some applications assume the
+ existence of the directory tree, reading it directly rather than
using the terminfo library calls.
- <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
+ <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 <EM>TERMINFO</EM> variable begins with "hex:" or "b64:", <EM>ncurses</EM> uses
- the remainder of that variable as a compiled terminal description.
+ the remainder of that variable as a compiled terminal description.
You might produce the base64 format using <STRONG><A HREF="infocmp.1m.html">infocmp(1m)</A></STRONG>:
TERMINFO="$(infocmp -0 -Q2 -q)"
export TERMINFO
- The compiled description is used if it corresponds to the terminal
+ The compiled description is used if it corresponds to the terminal
identified by the <EM>TERM</EM> variable.
- 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
+ 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 <EM>ncurses</EM> wrote, if any, is
+ <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> locations listed in the <EM>TERMINFO</EM><STRONG>_</STRONG><EM>DIRS</EM> environment variable
- <STRONG>o</STRONG> one or more locations whose names are configured and compiled
+ <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>
+ <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)
</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
+ 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
+ There is no corresponding feature in System V terminfo; it is an
extension developed for <EM>ncurses</EM>.
</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
+ 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
+ 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,
in that order.
The library may be configured to disregard the following variables when
- the current user is the superuser (root), or if the application uses
+ the current user is the superuser (root), or if the application uses
setuid or setgid permissions:
$TERMINFO, $TERMINFO_DIRS, $TERMPATH, as well as $HOME.
</PRE><H2><a name="h2-ALTERNATE-CONFIGURATIONS">ALTERNATE CONFIGURATIONS</a></H2><PRE>
- Several different configurations are possible, depending on the
- configure script options used when building <EM>ncurses</EM>. There are a few
- main options whose effects are visible to the applications developer
- using <EM>ncurses</EM>:
+ 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>
--disable-overwrite
The standard include for <EM>ncurses</EM> is as noted in <STRONG>SYNOPSIS</STRONG>:
<STRONG>#include</STRONG> <STRONG><curses.h></STRONG>
- This option is used to avoid filename conflicts when <EM>ncurses</EM> is
+ This option is used to avoid filename conflicts when <EM>ncurses</EM> is
not the main implementation of curses of the computer. If <EM>ncurses</EM>
- is installed disabling overwrite, it puts its headers in a
+ is installed disabling overwrite, it puts its headers in a
subdirectory, e.g.,
<STRONG>#include</STRONG> <STRONG><ncurses/curses.h></STRONG>
- It also omits a symbolic link which would allow you to use
+ It also omits a symbolic link which would allow you to use
<STRONG>-lcurses</STRONG> to build executables.
--enable-widec
- 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"
+ 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"
appended to them, i.e., instead of
<STRONG>-lncurses</STRONG>
<STRONG>-lncursesw</STRONG>
- You must also enable the wide-character features in the header
- file when compiling for the wide-character library to use the
- extended (wide-character) functions. The symbol which enables
+ You must also enable the wide-character features in the header
+ file when compiling for the wide-character library to use the
+ extended (wide-character) functions. The symbol which enables
these features has changed since XSI Curses, Issue 4:
- <STRONG>o</STRONG> Originally, the wide-character feature required the symbol
+ <STRONG>o</STRONG> Originally, the wide-character feature required the symbol
<STRONG>_XOPEN_SOURCE_EXTENDED</STRONG> but that was only valid for XPG4
(1996).
- <STRONG>o</STRONG> Later, that was deemed conflicting with <STRONG>_XOPEN_SOURCE</STRONG> defined
+ <STRONG>o</STRONG> Later, that was deemed conflicting with <STRONG>_XOPEN_SOURCE</STRONG> defined
to 500.
- <STRONG>o</STRONG> As of mid-2018, none of the features in this implementation
- require a <STRONG>_XOPEN_SOURCE</STRONG> feature greater than 600. However,
+ <STRONG>o</STRONG> As of mid-2018, none of the features in this implementation
+ require a <STRONG>_XOPEN_SOURCE</STRONG> feature greater than 600. However,
X/Open Curses, Issue 7 (2009) recommends defining it to 700.
- <STRONG>o</STRONG> Alternatively, you can enable the feature by defining
- <STRONG>NCURSES_WIDECHAR</STRONG> with the caveat that some other header file
- than <STRONG>curses.h</STRONG> may require a specific value for <STRONG>_XOPEN_SOURCE</STRONG>
+ <STRONG>o</STRONG> Alternatively, you can enable the feature by defining
+ <STRONG>NCURSES_WIDECHAR</STRONG> with the caveat that some other header file
+ than <STRONG>curses.h</STRONG> may require a specific value for <STRONG>_XOPEN_SOURCE</STRONG>
(or a system-specific symbol).
- The <EM>curses.h</EM> header file installed for the wide-character library
- is designed to be compatible with the non-wide library's header.
- Only the size of the <EM>WINDOW</EM> structure differs; few applications
+ The <EM>curses.h</EM> header file installed for the wide-character library
+ is designed to be compatible with the non-wide library's header.
+ Only the size of the <EM>WINDOW</EM> structure differs; few applications
require more than pointers to <EM>WINDOW</EM>s.
If the headers are installed allowing overwrite, the wide-
- character library's headers should be installed last, to allow
+ character library's headers should be installed last, to allow
applications to be built using either library from the same set of
headers.
--with-pthread
- The configure script renames the library. All of the library
- names have a "t" appended to them (before any "w" added by
+ The configure script renames the library. All of the library
+ names have a "t" appended to them (before any "w" added by
<STRONG>--enable-widec</STRONG>).
The global variables such as <STRONG>LINES</STRONG> are replaced by macros to allow
read-only access. At the same time, setter-functions are provided
- to set these values. Some applications (very few) may require
+ to set these values. Some applications (very few) may require
changes to work with this convention.
--with-shared
--with-debug
--with-profile
- 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
+ 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
- Low-level functions which do not depend upon whether the library
+ Low-level functions which do not depend upon whether the library
supports wide-characters, are provided in the tinfo library.
- By doing this, it is possible to share the tinfo library between
- wide/normal configurations as well as reduce the size of the
+ By doing this, it is possible to share the tinfo library between
+ wide/normal configurations as well as reduce the size of the
library when only low-level functions are needed.
Those functions are described in these pages:
- <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
- The <STRONG>trace</STRONG> function normally resides in the debug library, but it
- is sometimes useful to configure this in the shared library.
+ 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
than assuming it is always in the debug library.
</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
+
+ <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.
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.
+ <EM>ncurses</EM> enables an application to capture mouse events on certain
+ terminals, including <EM>xterm;</EM> see <STRONG><A HREF="curs_mouse.3x.html">curs_mouse(3x)</A></STRONG>.
- 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> 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>.
+ <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>.
-</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> extends the fixed set of function key capabilities specified by
+ X/Open Curses by allowing the application programmer to define
+ additional key sequences 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>, and <STRONG><A HREF="keyok.3x.html">keyok(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> 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>.
+ An <EM>ncurses</EM> application can choose to hide the internal details of
+ <EM>WINDOW</EM> structures, instead using accessor functions such as
+ <STRONG><A HREF="curs_opaque.3x.html">is_scrollok(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.
+ <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>.
- Unlike other implementations, this one checks parameters such as
- pointers to WINDOW structures to ensure they are not null. The main
- reason for providing this behavior is to guard against programmer
- error. The standard interface does not provide a way for the library
- to tell an 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> 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.
+ Some extensions are only available if <EM>ncurses</EM> is compiled to support
+ them; see section "ALTERNATE CONFIGURATIONS" above.
-</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:
+ <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>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> 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 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> 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 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.
+ <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> 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 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.
+</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 its enhanced features.
- <STRONG>o</STRONG> The WINDOW 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.
+ Differences between X/Open Curses and <EM>ncurses</EM> are documented in the
+ "PORTABILITY" sections of applicable man pages.
- <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><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, 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.
-</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
+</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
+ bytes. This method is slightly more expensive, but narrows the
+ interface to the Unix kernel significantly and increases the package's
portability correspondingly.
-</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
+</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:
- The inclusion of <curses.h> may make visible all symbols from the
+ The inclusion of <curses.h> may make visible all symbols from the
headers <stdio.h>, <term.h>, <termios.h>, and <wchar.h>.
Here is a more complete story:
- <STRONG>o</STRONG> Starting with BSD curses, all implementations have included
+ <STRONG>o</STRONG> Starting with BSD curses, all implementations have included
<stdio.h>.
- BSD curses included <curses.h> and <unctrl.h> from an internal
+ BSD curses included <curses.h> and <unctrl.h> from an internal
header file <EM>curses.ext</EM> ("ext" abbreviated "externs").
- BSD curses used <stdio.h> internally (for <STRONG>printw</STRONG> and <STRONG>scanw</STRONG>), but
+ BSD curses used <stdio.h> internally (for <STRONG>printw</STRONG> and <STRONG>scanw</STRONG>), but
nothing in <curses.h> itself relied upon <stdio.h>.
- <STRONG>o</STRONG> SVr2 curses added <STRONG><A HREF="curs_initscr.3x.html">newterm(3x)</A></STRONG>, which relies upon <stdio.h>. That
+ <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>.
SVr4 curses added <STRONG>putwin</STRONG> and <STRONG>getwin</STRONG>, which also use <stdio.h>.
X/Open Curses documents all three of these functions.
- SVr4 curses and X/Open Curses do not require the developer to
+ 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.
As a result, standard <curses.h> will always include <stdio.h>.
- <STRONG>o</STRONG> X/Open Curses is inconsistent with respect to SVr4 regarding
+ <STRONG>o</STRONG> X/Open Curses is inconsistent with respect to SVr4 regarding
<unctrl.h>.
- As noted in <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>, <EM>ncurses</EM> includes <unctrl.h> from
+ 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).
<STRONG>o</STRONG> X/Open's comments about <term.h> and <termios.h> may refer to HP-UX
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.
- AIX curses includes <term.h> and <termios.h>. Again, <EM>ncurses</EM> (and
+ AIX curses includes <term.h> and <termios.h>. Again, <EM>ncurses</EM> (and
Solaris curses) do not.
- <STRONG>o</STRONG> X/Open says that <curses.h> <EM>may</EM> include <term.h>, but there is no
+ <STRONG>o</STRONG> X/Open says that <curses.h> <EM>may</EM> include <term.h>, but there is no
requirement that it do that.
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
+ <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>.
- Because <EM>ncurses</EM> header files include the headers needed to define
+ 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>
+ in any order. But for portability, you should include <curses.h>
before <term.h>.
- <STRONG>o</STRONG> X/Open Curses says <EM>"may</EM> <EM>make</EM> <EM>visible"</EM> because including a header
+ <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).
- 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
+ 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.
- <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>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.
- 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
+ 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-
+ 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>.
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>
+ 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.
-ncurses 6.4 202
3-12-17 <STRONG><A HREF="ncurses.3x.html">ncurses(3x)</A></STRONG>
+ncurses 6.4 202
4-01-13 <STRONG><A HREF="ncurses.3x.html">ncurses(3x)</A></STRONG>
</PRE>
<div class="nav">
<ul>
<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-CC-_command-character_">CC (command character)</a></li>
<li><a href="#h3-BAUDRATE">BAUDRATE</a></li>
<li><a href="#h3-COLUMNS">COLUMNS</a></li>
<li><a href="#h3-ESCDELAY">ESCDELAY</a></li>
<li><a href="#h2-EXTENSIONS">EXTENSIONS</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>
+<li><a href="#h3-Error-Checking">Error Checking</a></li>
+<li><a href="#h3-Padding-Differences">Padding Differences</a></li>
+<li><a href="#h3-Header-Files">Header Files</a></li>
</ul>
</li>
<li><a href="#h2-AUTHORS">AUTHORS</a></li>
projects / ncurses.git / blobdiff