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-<H1>curs_util 3x</H1>
-<HR>
+<H1 class="no-header">curs_util 3x 2023-10-14 ncurses 6.4 Library calls</H1>
<PRE>
-<!-- Manpage converted by man2html 3.0.1 -->
-<STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG> <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>
+<STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG> Library calls <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>
-</PRE>
-<H2>NAME</H2><PRE>
- <STRONG>delay_output</STRONG>, <STRONG>filter</STRONG>, <STRONG>flushinp</STRONG>, <STRONG>getwin</STRONG>, <STRONG>key_name</STRONG>, <STRONG>keyname</STRONG>,
- <STRONG>nofilter</STRONG>, <STRONG>putwin</STRONG>, <STRONG>unctrl</STRONG>, <STRONG>use_env</STRONG>, <STRONG>wunctrl</STRONG> - miscellaneous
- <STRONG>curses</STRONG> utility routines
+</PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
+ <STRONG>delay_output</STRONG>, <STRONG>filter</STRONG>, <STRONG>flushinp</STRONG>, <STRONG>getwin</STRONG>, <STRONG>key_name</STRONG>, <STRONG>keyname</STRONG>, <STRONG>nofilter</STRONG>,
+ <STRONG>putwin</STRONG>, <STRONG>unctrl</STRONG>, <STRONG>use_env</STRONG>, <STRONG>use_tioctl</STRONG>, <STRONG>wunctrl</STRONG> - miscellaneous <EM>curses</EM>
+ utility routines
-</PRE>
-<H2>SYNOPSIS</H2><PRE>
+</PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
<STRONG>#include</STRONG> <STRONG><curses.h></STRONG>
- <STRONG>char</STRONG> <STRONG>*unctrl(chtype</STRONG> <STRONG>c);</STRONG>
- <STRONG>wchar_t</STRONG> <STRONG>*wunctrl(cchar_t</STRONG> <STRONG>*c);</STRONG>
- <STRONG>char</STRONG> <STRONG>*keyname(int</STRONG> <STRONG>c);</STRONG>
- <STRONG>char</STRONG> <STRONG>*key_name(wchar_t</STRONG> <STRONG>w);</STRONG>
+ <STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*unctrl(chtype</STRONG> <EM>c</EM><STRONG>);</STRONG>
+ <STRONG>wchar_t</STRONG> <STRONG>*wunctrl(cchar_t</STRONG> <STRONG>*</STRONG><EM>c</EM><STRONG>);</STRONG>
+
+ <STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*keyname(int</STRONG> <EM>c</EM><STRONG>);</STRONG>
+ <STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*key_name(wchar_t</STRONG> <EM>w</EM><STRONG>);</STRONG>
+
<STRONG>void</STRONG> <STRONG>filter(void);</STRONG>
- <STRONG>void</STRONG> <STRONG>nofilter(void);</STRONG>
- <STRONG>void</STRONG> <STRONG>use_env(bool</STRONG> <STRONG>f);</STRONG>
- <STRONG>int</STRONG> <STRONG>putwin(WINDOW</STRONG> <STRONG>*win,</STRONG> <STRONG>FILE</STRONG> <STRONG>*filep);</STRONG>
- <STRONG>WINDOW</STRONG> <STRONG>*getwin(FILE</STRONG> <STRONG>*filep);</STRONG>
- <STRONG>int</STRONG> <STRONG>delay_output(int</STRONG> <STRONG>ms);</STRONG>
+
+ <STRONG>void</STRONG> <STRONG>use_env(bool</STRONG> <EM>f</EM><STRONG>);</STRONG>
+
+ <STRONG>int</STRONG> <STRONG>putwin(WINDOW</STRONG> <STRONG>*</STRONG><EM>win</EM><STRONG>,</STRONG> <STRONG>FILE</STRONG> <STRONG>*</STRONG><EM>filep</EM><STRONG>);</STRONG>
+ <STRONG>WINDOW</STRONG> <STRONG>*getwin(FILE</STRONG> <STRONG>*</STRONG><EM>filep</EM><STRONG>);</STRONG>
+
+ <STRONG>int</STRONG> <STRONG>delay_output(int</STRONG> <EM>ms</EM><STRONG>);</STRONG>
<STRONG>int</STRONG> <STRONG>flushinp(void);</STRONG>
+ <EM>/*</EM> <EM>extensions</EM> <EM>*/</EM>
+ <STRONG>void</STRONG> <STRONG>nofilter(void);</STRONG>
+ <STRONG>void</STRONG> <STRONG>use_tioctl(bool</STRONG> <EM>f</EM><STRONG>);</STRONG>
-</PRE>
-<H2>DESCRIPTION</H2><PRE>
- The <STRONG>unctrl</STRONG> routine returns a character string which is a
- printable representation of the character <EM>c</EM>, ignoring at-
- tributes. Control characters are displayed in the <STRONG>^</STRONG><EM>X</EM> no-
- tation. Printing characters are displayed as is. The
- corresponding <STRONG>wunctrl</STRONG> returns a printable representation
- of a wide-character.
-
- The <STRONG>keyname</STRONG> routine returns a character string correspond-
- ing to the key <EM>c</EM>:
-
- - Printable characters are displayed as themselves,
- e.g., a one-character string containing the key.
-
- - Control characters are displayed in the <STRONG>^</STRONG><EM>X</EM> notation.
-
- - DEL (character 127) is displayed as <STRONG>^?</STRONG>.
-
- - Values above 128 are either meta characters (if the
- screen has not been initialized, or if <STRONG>meta</STRONG> has been
- called with a TRUE parameter), shown in the <STRONG>M-</STRONG><EM>X</EM> no-
- tation, or are displayed as themselves. In the lat-
- ter case, the values may not be printable; this fol-
- lows the X/Open specification.
-
- - Values above 256 may be the names of the names of
- function keys.
-
- - Otherwise (if there is no corresponding name) the
- function returns null, to denote an error. X/Open
- also lists an "UNKNOWN KEY" return value, which some
- implementations return rather than null.
-
- The corresponding <STRONG>key_name</STRONG> returns a character string cor-
- responding to the wide-character value <EM>w</EM>. The two func-
- tions do not return the same set of strings; the latter
- returns null where the former would display a meta charac-
- ter.
-
- The <STRONG>filter</STRONG> routine, if used, must be called before <STRONG>initscr</STRONG>
- or <STRONG>newterm</STRONG> are called. The effect is that, during those
- calls, <STRONG>LINES</STRONG> is set to 1; the capabilities <STRONG>clear</STRONG>, <STRONG>cup</STRONG>,
- <STRONG>cud</STRONG>, <STRONG>cud1</STRONG>, <STRONG>cuu1</STRONG>, <STRONG>cuu</STRONG>, <STRONG>vpa</STRONG> are disabled; and the <STRONG>home</STRONG>
- string is set to the value of <STRONG>cr</STRONG>.
-
- The <STRONG>nofilter</STRONG> routine cancels the effect of a preceding
- <STRONG>filter</STRONG> call. That allows the caller to initialize a
- screen on a different device, using a different value of
- <STRONG>$TERM</STRONG>. The limitation arises because the <STRONG>filter</STRONG> routine
- modifies the in-memory copy of the terminal information.
-
- The <STRONG>use_env</STRONG> routine, if used, is called before <STRONG>initscr</STRONG> or
- <STRONG>newterm</STRONG> are called. When called with <STRONG>FALSE</STRONG> as an argu-
- ment, the values of <STRONG>lines</STRONG> and <STRONG>columns</STRONG> specified in the
- <EM>terminfo</EM> database will be used, even if environment vari-
- ables <STRONG>LINES</STRONG> and <STRONG>COLUMNS</STRONG> (used by default) are set, or if
- <STRONG>curses</STRONG> is running in a window (in which case default be-
- havior would be to use the window size if <STRONG>LINES</STRONG> and <STRONG>COL-</STRONG>
- <STRONG>UMNS</STRONG> are not set). Note that setting <STRONG>LINES</STRONG> or <STRONG>COLUMNS</STRONG>
- overrides the corresponding size which may be obtained
- from the operating system.
-
- The <STRONG>putwin</STRONG> routine writes all data associated with window
- <EM>win</EM> into the file to which <EM>filep</EM> points. This information
- can be later retrieved using the <STRONG>getwin</STRONG> function.
-
- The <STRONG>getwin</STRONG> routine reads window related data stored in the
- file by <STRONG>putwin</STRONG>. The routine then creates and initializes
- a new window using that data. It returns a pointer to the
- new window.
-
- The <STRONG>delay_output</STRONG> routine inserts an <EM>ms</EM> millisecond pause
- in output. This routine should not be used extensively
- because padding characters are used rather than a CPU
- pause. If no padding character is specified, this uses
- <STRONG>napms</STRONG> to perform the delay.
-
- The <STRONG>flushinp</STRONG> routine throws away any typeahead that has
- been typed by the user and has not yet been read by the
- program.
+</PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
+
+</PRE><H3><a name="h3-unctrl">unctrl</a></H3><PRE>
+ The <STRONG>unctrl</STRONG> routine returns a character string which is a printable
+ representation of the character <EM>c</EM>:
+
+ <STRONG>o</STRONG> Printable characters are displayed as themselves, e.g., a one-
+ character string containing the key.
+
+ <STRONG>o</STRONG> Control characters are displayed in the <STRONG>^</STRONG><EM>X</EM> notation.
+
+ <STRONG>o</STRONG> Printing characters are displayed as is.
+
+ <STRONG>o</STRONG> DEL (character 127) is displayed as <STRONG>^?</STRONG>.
+
+ <STRONG>o</STRONG> Values above 128 are either meta characters (if the screen has not
+ been initialized, or if <STRONG><A HREF="curs_inopts.3x.html">meta(3x)</A></STRONG> has been called with a <STRONG>TRUE</STRONG>
+ parameter), shown in the <STRONG>M-</STRONG><EM>X</EM> notation, or are displayed as
+ themselves. In the latter case, the values may not be printable;
+ this follows the X/Open specification.
+
+ The corresponding <STRONG>wunctrl</STRONG> returns a printable representation of a
+ complex character <EM>c</EM>.
+
+ In both <STRONG>unctrl</STRONG> and <STRONG>wunctrl</STRONG> the attributes and color associated with the
+ character parameter are ignored.
+
+
+</PRE><H3><a name="h3-keyname_key_name">keyname/key_name</a></H3><PRE>
+ The <STRONG>keyname</STRONG> routine returns a character string corresponding to the key
+ <EM>c</EM>. Key codes are different from character codes.
+
+ <STRONG>o</STRONG> Key codes below 256 are characters. They are displayed using
+ <STRONG>unctrl</STRONG>.
+
+ <STRONG>o</STRONG> Values above 256 may be the codes for function keys. The function
+ key name is displayed.
+
+ <STRONG>o</STRONG> Otherwise (if there is no corresponding name and the key is not a
+ character) the function returns null, to denote an error. X/Open
+ also lists an "UNKNOWN KEY" return value, which some
+ implementations return rather than null.
+
+ The corresponding <STRONG>key_name</STRONG> returns a multibyte character string
+ corresponding to the wide-character value <EM>w</EM>. The two functions
+ (<STRONG>keyname</STRONG> and <STRONG>key_name</STRONG>) do not return the same set of strings:
+
+ <STRONG>o</STRONG> <STRONG>keyname</STRONG> returns null where <STRONG>key_name</STRONG> would display a meta character.
+
+ <STRONG>o</STRONG> <STRONG>key_name</STRONG> does not return the name of a function key.
+
+
+</PRE><H3><a name="h3-filter_nofilter">filter/nofilter</a></H3><PRE>
+ The <STRONG>filter</STRONG> routine, if used, must be called before <STRONG>initscr</STRONG> or <STRONG>newterm</STRONG>
+ are called. Calling <STRONG>filter</STRONG> causes these changes in initialization:
+
+ <STRONG>o</STRONG> <STRONG>LINES</STRONG> is set to 1;
+
+ <STRONG>o</STRONG> the capabilities <STRONG>clear</STRONG>, <STRONG>cud1</STRONG>, <STRONG>cud</STRONG>, <STRONG>cup</STRONG>, <STRONG>cuu1</STRONG>, <STRONG>cuu</STRONG>, <STRONG>vpa</STRONG> are
+ disabled;
+
+ <STRONG>o</STRONG> the capability <STRONG>ed</STRONG> is disabled if <STRONG>bce</STRONG> is set;
+
+ <STRONG>o</STRONG> and the <STRONG>home</STRONG> string is set to the value of <STRONG>cr</STRONG>.
+
+ The <STRONG>nofilter</STRONG> routine cancels the effect of a preceding <STRONG>filter</STRONG> call.
+ That allows the caller to initialize a screen on a different device,
+ using a different value of <STRONG>$TERM</STRONG>. The limitation arises because the
+ <STRONG>filter</STRONG> routine modifies the in-memory copy of the terminal information.
+
+
+</PRE><H3><a name="h3-use_env">use_env</a></H3><PRE>
+ The <STRONG>use_env</STRONG> routine, if used, should be called before <STRONG>initscr</STRONG> or
+ <STRONG>newterm</STRONG> are called (because those compute the screen size). It
+ modifies the way <EM>ncurses</EM> treats environment variables when determining
+ the screen size.
+
+ <STRONG>o</STRONG> Normally <EM>ncurses</EM> looks first at the terminal database for the
+ screen size.
+
+ If <STRONG>use_env</STRONG> was called with <STRONG>FALSE</STRONG> for parameter, it stops here
+ unless <STRONG>use_tioctl</STRONG> was also called with <STRONG>TRUE</STRONG> for parameter.
+
+ <STRONG>o</STRONG> Then it asks for the screen size via operating system calls. If
+ successful, it overrides the values from the terminal database.
+
+ <STRONG>o</STRONG> Finally (unless <STRONG>use_env</STRONG> was called with <STRONG>FALSE</STRONG> parameter), <STRONG>ncurses</STRONG>
+ examines the <STRONG>LINES</STRONG> or <STRONG>COLUMNS</STRONG> environment variables, using a value
+ in those to override the results from the operating system or
+ terminal database.
+
+ <STRONG>Ncurses</STRONG> also updates the screen size in response to <STRONG>SIGWINCH</STRONG>,
+ unless overridden by the <STRONG>LINES</STRONG> or <STRONG>COLUMNS</STRONG> environment variables,
-</PRE>
-<H2>RETURN VALUE</H2><PRE>
- Except for <STRONG>flushinp</STRONG>, routines that return an integer re-
- turn <STRONG>ERR</STRONG> upon failure and <STRONG>OK</STRONG> (SVr4 specifies only "an in-
- teger value other than <STRONG>ERR</STRONG>") upon successful completion.
+
+</PRE><H3><a name="h3-use_tioctl">use_tioctl</a></H3><PRE>
+ The <STRONG>use_tioctl</STRONG> routine, if used, should be called before <STRONG>initscr</STRONG> or
+ <STRONG>newterm</STRONG> are called (because those compute the screen size). After
+ <STRONG>use_tioctl</STRONG> is called with <STRONG>TRUE</STRONG> as an argument, <STRONG>ncurses</STRONG> modifies the
+ last step in its computation of screen size as follows:
+
+ <STRONG>o</STRONG> checks if the <STRONG>LINES</STRONG> and <STRONG>COLUMNS</STRONG> environment variables are set to a
+ number greater than zero.
+
+ <STRONG>o</STRONG> for each, <STRONG>ncurses</STRONG> updates the corresponding environment variable
+ with the value that it has obtained via operating system call or
+ from the terminal database.
+
+ <STRONG>o</STRONG> <STRONG>ncurses</STRONG> re-fetches the value of the environment variables so that
+ it is still the environment variables which set the screen size.
+
+ The <STRONG>use_env</STRONG> and <STRONG>use_tioctl</STRONG> routines combine as follows.
+
+ <STRONG>use_env</STRONG> <STRONG>use_tioctl</STRONG> <STRONG>Summary</STRONG>
+ -----------------------------------------------------------------
+ <STRONG>TRUE</STRONG> <STRONG>FALSE</STRONG> This is the default behavior. <EM>ncurses</EM>
+ uses operating system calls unless
+ overridden by <STRONG>LINES</STRONG> or <STRONG>COLUMNS</STRONG>
+ environment variables; default.
+ <STRONG>TRUE</STRONG> <STRONG>TRUE</STRONG> <EM>ncurses</EM> updates <STRONG>LINES</STRONG> and <STRONG>COLUMNS</STRONG> based
+ on operating system calls.
+ <STRONG>FALSE</STRONG> <STRONG>TRUE</STRONG> <EM>ncurses</EM> ignores <STRONG>LINES</STRONG> and <STRONG>COLUMNS</STRONG>, using
+ operating system calls to obtain size.
+
+
+</PRE><H3><a name="h3-putwin_getwin">putwin/getwin</a></H3><PRE>
+ The <STRONG>putwin</STRONG> routine writes all data associated with window (or pad) <EM>win</EM>
+ into the file to which <EM>filep</EM> points. This information can be later
+ retrieved using the <STRONG>getwin</STRONG> function.
+
+ The <STRONG>getwin</STRONG> routine reads window related data stored in the file by
+ <STRONG>putwin</STRONG>. The routine then creates and initializes a new window using
+ that data. It returns a pointer to the new window. There are a few
+ caveats:
+
+ <STRONG>o</STRONG> the data written is a copy of the <STRONG>WINDOW</STRONG> structure, and its
+ associated character cells. The format differs between the wide-
+ character (<STRONG>ncursesw</STRONG>) and non-wide (<STRONG>ncurses</STRONG>) libraries. You can
+ transfer data between the two, however.
+
+ <STRONG>o</STRONG> the retrieved window is always created as a top-level window (or
+ pad), rather than a subwindow.
+
+ <STRONG>o</STRONG> the window's character cells contain the color pair <EM>value</EM>, but not
+ the actual color <EM>numbers</EM>. If cells in the retrieved window use
+ color pairs which have not been created in the application using
+ <STRONG>init_pair</STRONG>, they will not be colored when the window is refreshed.
+
+
+</PRE><H3><a name="h3-delay_output">delay_output</a></H3><PRE>
+ The <STRONG>delay_output</STRONG> routine inserts an <EM>ms</EM> millisecond pause in output.
+ Employ this function judiciously when terminal output uses padding,
+ because <EM>ncurses</EM> transmits null characters (consuming CPU and I/O
+ resources) instead of sleeping and requesting resumption from the
+ operating system. Padding is used unless:
+
+ <STRONG>o</STRONG> the terminal description has <STRONG>npc</STRONG> (<STRONG>no_pad_char</STRONG>) capability, or
+
+ <STRONG>o</STRONG> the environment variable <STRONG>NCURSES_NO_PADDING</STRONG> is set.
+
+ If padding is not in use, <EM>ncurses</EM> uses <STRONG>napms</STRONG> to perform the delay. If
+ the value of <EM>ms</EM> exceeds 30,000 (thirty seconds), it is capped at that
+ value.
+
+
+</PRE><H3><a name="h3-flushinp">flushinp</a></H3><PRE>
+ The <STRONG>flushinp</STRONG> routine throws away any typeahead that has been typed by
+ the user and has not yet been read by the program.
+
+
+</PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
+ Except for <STRONG>flushinp</STRONG>, routines that return an integer return <STRONG>ERR</STRONG> upon
+ failure and <STRONG>OK</STRONG> (SVr4 specifies only "an integer value other than <STRONG>ERR</STRONG>")
+ upon successful completion.
Routines that return pointers return <STRONG>NULL</STRONG> on error.
- X/Open does not define any error conditions. In this im-
- plementation
+ X/Open does not define any error conditions. In this implementation
<STRONG>flushinp</STRONG>
- returns an error if the terminal was not initial-
- ized.
-
- <STRONG>meta</STRONG> returns an error if the terminal was not initial-
- ized.
+ returns an error if the terminal was not initialized.
<STRONG>putwin</STRONG>
- returns an error if the associated <STRONG>fwrite</STRONG> calls
- return an error.
+ returns an error if the associated <STRONG>fwrite</STRONG> calls return an
+ error.
-</PRE>
-<H2>PORTABILITY</H2><PRE>
- The XSI Curses standard, Issue 4 describes these func-
- tions. It states that <STRONG>unctrl</STRONG> and <STRONG>wunctrl</STRONG> will return a
- null pointer if unsuccessful, but does not define any er-
- ror conditions. This implementation checks for three cas-
- es:
-
- - the parameter is a 7-bit US-ASCII code. This
- is the case that X/Open Curses documented.
-
- - the parameter is in the range 128-159, i.e., a
- C1 control code. If <STRONG>use_legacy_coding</STRONG> has
- been called with a <STRONG>2</STRONG> parameter, <STRONG>unctrl</STRONG> returns
- the parameter, i.e., a one-character string
- with the parameter as the first character.
- Otherwise, it returns ``~@'', ``~A'', etc.,
- analogous to ``^@'', ``^A'', C0 controls.
-
- X/Open Curses does not document whether <STRONG>unctrl</STRONG>
- can be called before initializing curses.
- This implementation permits that, and returns
- the ``~@'', etc., values in that case.
-
- - parameter values outside the 0 to 255 range.
- <STRONG>unctrl</STRONG> returns a null pointer.
-
- The SVr4 documentation describes the action of <STRONG>filter</STRONG> only
- in the vaguest terms. The description here is adapted
- from the XSI Curses standard (which erroneously fails to
- describe the disabling of <STRONG>cuu</STRONG>).
-
- The strings returned by <STRONG>unctrl</STRONG> in this implementation are
- determined at compile time, showing C1 controls from the
- upper-128 codes with a `~' prefix rather than `^'. Other
- implementations have different conventions. For example,
- they may show both sets of control characters with `^',
- and strip the parameter to 7 bits. Or they may ignore C1
- controls and treat all of the upper-128 codes as print-
- able. This implementation uses 8 bits but does not modify
- the string to reflect locale. The <STRONG>use_legacy_coding</STRONG> func-
- tion allows the caller to change the output of <STRONG>unctrl</STRONG>.
-
- Likewise, the <STRONG>meta</STRONG> function allows the caller to change
- the output of <STRONG>keyname</STRONG>, i.e., it determines whether to use
- the `M-' prefix for ``meta'' keys (codes in the range 128
- to 255). Both <STRONG>use_legacy_coding</STRONG> and <STRONG>meta</STRONG> succeed only af-
- ter curses is initialized. X/Open Curses does not docu-
- ment the treatment of codes 128 to 159. When treating
- them as ``meta'' keys (or if <STRONG>keyname</STRONG> is called before ini-
- tializing curses), this implementation returns strings
- ``M-^@'', ``M-^A'', etc.
-
- The <STRONG>keyname</STRONG> function may return the names of user-defined
- string capabilities which are defined in the terminfo en-
- try via the <STRONG>-x</STRONG> option of <STRONG>tic</STRONG>. This implementation auto-
- matically assigns at run-time keycodes to user-defined
- strings which begin with "k". The keycodes start at
- KEY_MAX, but are not guaranteed to be the same value for
- different runs because user-defined codes are merged from
- all terminal descriptions which have been loaded. The
- <STRONG>use_extended_names</STRONG> function controls whether this data is
- loaded when the terminal description is read by the li-
- brary.
-
- The <STRONG>nofilter</STRONG> routine is specific to ncurses. It was not
- supported on Version 7, BSD or System V implementations.
- It is recommended that any code depending on ncurses ex-
- tensions be conditioned using NCURSES_VERSION.
+</PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
+</PRE><H3><a name="h3-filter">filter</a></H3><PRE>
+ The SVr4 documentation describes the action of <STRONG>filter</STRONG> only in the
+ vaguest terms. The description here is adapted from the XSI Curses
+ standard (which erroneously fails to describe the disabling of <STRONG>cuu</STRONG>).
+
+
+</PRE><H3><a name="h3-delay_output-padding">delay_output padding</a></H3><PRE>
+ The limitation to 30 seconds and the use of <STRONG>napms</STRONG> differ from other
+ implementations.
+
+ <STRONG>o</STRONG> SVr4 curses does not delay if no padding character is available.
-</PRE>
-<H2>SEE ALSO</H2><PRE>
- <STRONG><A HREF="legacy_coding.3x.html">legacy_coding(3x)</A></STRONG>, <STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG>, <STRONG><A HREF="curs_initscr.3x.html">curs_initscr(3x)</A></STRONG>, <STRONG>curs_ker-</STRONG>
- <STRONG><A HREF="curs_kernel.3x.html">nel(3x)</A></STRONG>, <STRONG><A HREF="curs_scr_dump.3x.html">curs_scr_dump(3x)</A></STRONG>, <STRONG><A HREF="legacy_coding.3x.html">legacy_coding(3x)</A></STRONG>.
+ <STRONG>o</STRONG> NetBSD curses uses <STRONG>napms</STRONG> when no padding character is available,
+ but does not take timing into account when using the padding
+ character.
+
+ Neither limits the delay.
+
+
+</PRE><H3><a name="h3-keyname">keyname</a></H3><PRE>
+ The <STRONG>keyname</STRONG> function may return the names of user-defined string
+ capabilities which are defined in the terminfo entry via the <STRONG>-x</STRONG> option
+ of <STRONG>tic</STRONG>. This implementation automatically assigns at run-time keycodes
+ to user-defined strings which begin with "k". The keycodes start at
+ KEY_MAX, but are not guaranteed to be the same value for different runs
+ because user-defined codes are merged from all terminal descriptions
+ which have been loaded. The <STRONG><A HREF="curs_extend.3x.html">use_extended_names(3x)</A></STRONG> function controls
+ whether this data is loaded when the terminal description is read by
+ the library.
+
+
+</PRE><H3><a name="h3-nofilter_use_tioctl">nofilter/use_tioctl</a></H3><PRE>
+ The <STRONG>nofilter</STRONG> and <STRONG>use_tioctl</STRONG> routines are specific to <STRONG>ncurses</STRONG>. They
+ were not supported on Version 7, BSD or System V implementations. It
+ is recommended that any code depending on <STRONG>ncurses</STRONG> extensions be
+ conditioned using <STRONG>NCURSES_VERSION</STRONG>.
+
+
+</PRE><H3><a name="h3-putwin_getwin-file-format">putwin/getwin file-format</a></H3><PRE>
+ The <STRONG>putwin</STRONG> and <STRONG>getwin</STRONG> functions have several issues with portability:
+
+ <STRONG>o</STRONG> The files written and read by these functions use an
+ implementation-specific format. Although the format is an obvious
+ target for standardization, it has been overlooked.
+
+ Interestingly enough, according to the copyright dates in Solaris
+ source, the functions (along with <STRONG>scr_init</STRONG>, etc.) originated with
+ the University of California, Berkeley (in 1982) and were later (in
+ 1988) incorporated into SVr4. Oddly, there are no such functions
+ in the 4.3BSD curses sources.
+
+ <STRONG>o</STRONG> Most implementations simply dump the binary <STRONG>WINDOW</STRONG> structure to the
+ file. These include SVr4 curses, NetBSD and PDCurses, as well as
+ older <STRONG>ncurses</STRONG> versions. This implementation (as well as the X/Open
+ variant of Solaris curses, dated 1995) uses textual dumps.
+
+ The implementations which use binary dumps use block-I/O (the
+ <STRONG>fwrite</STRONG> and <STRONG>fread</STRONG> functions). Those that use textual dumps use
+ buffered-I/O. A few applications may happen to write extra data in
+ the file using these functions. Doing that can run into problems
+ mixing block- and buffered-I/O. This implementation reduces the
+ problem on writes by flushing the output. However, reading from a
+ file written using mixed schemes may not be successful.
+
+
+</PRE><H3><a name="h3-unctrl_wunctrl">unctrl/wunctrl</a></H3><PRE>
+ The XSI Curses standard, Issue 4 describes these functions. It states
+ that <STRONG>unctrl</STRONG> and <STRONG>wunctrl</STRONG> will return a null pointer if unsuccessful, but
+ does not define any error conditions. This implementation checks for
+ three cases:
+
+ <STRONG>o</STRONG> the parameter is a 7-bit US-ASCII code. This is the case that
+ X/Open Curses documented.
+
+ <STRONG>o</STRONG> the parameter is in the range 128-159, i.e., a C1 control code. If
+ <STRONG><A HREF="legacy_coding.3x.html">use_legacy_coding(3x)</A></STRONG> has been called with a <STRONG>2</STRONG> parameter, <STRONG>unctrl</STRONG>
+ returns the parameter, i.e., a one-character string with the
+ parameter as the first character. Otherwise, it returns "~@",
+ "~A", etc., analogous to "^@", "^A", C0 controls.
+
+ X/Open Curses does not document whether <STRONG>unctrl</STRONG> can be called before
+ initializing curses. This implementation permits that, and returns
+ the "~@", etc., values in that case.
+
+ <STRONG>o</STRONG> parameter values outside the 0 to 255 range. <STRONG>unctrl</STRONG> returns a null
+ pointer.
+
+ The strings returned by <STRONG>unctrl</STRONG> in this implementation are determined at
+ compile time, showing C1 controls from the upper-128 codes with a "~"
+ prefix rather than "^". Other implementations have different
+ conventions. For example, they may show both sets of control
+ characters with "^", and strip the parameter to 7 bits. Or they may
+ ignore C1 controls and treat all of the upper-128 codes as printable.
+ This implementation uses 8 bits but does not modify the string to
+ reflect locale. The <STRONG><A HREF="legacy_coding.3x.html">use_legacy_coding(3x)</A></STRONG> function allows the caller
+ to change the output of <STRONG>unctrl</STRONG>.
+ Likewise, the <STRONG><A HREF="curs_inopts.3x.html">meta(3x)</A></STRONG> function allows the caller to change the output
+ of <STRONG>keyname</STRONG>, i.e., it determines whether to use the "M-" prefix for
+ "meta" keys (codes in the range 128 to 255). Both
+ <STRONG><A HREF="legacy_coding.3x.html">use_legacy_coding(3x)</A></STRONG> and <STRONG><A HREF="curs_inopts.3x.html">meta(3x)</A></STRONG> succeed only after curses is
+ initialized. X/Open Curses does not document the treatment of codes
+ 128 to 159. When treating them as "meta" keys (or if <STRONG>keyname</STRONG> is called
+ before initializing curses), this implementation returns strings
+ "M-^@", "M-^A", etc.
+ X/Open Curses documents <STRONG>unctrl</STRONG> as declared in <STRONG><unctrl.h></STRONG>, which <STRONG>ncurses</STRONG>
+ does. However, <STRONG>ncurses</STRONG>' <STRONG><curses.h></STRONG> includes <STRONG><unctrl.h></STRONG>, matching the
+ behavior of SVr4 curses. Other implementations may not do that.
- <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>
+
+</PRE><H3><a name="h3-use_env_use_tioctl">use_env/use_tioctl</a></H3><PRE>
+ If <STRONG>ncurses</STRONG> is configured to provide the sp-functions extension, the
+ state of <STRONG>use_env</STRONG> and <STRONG>use_tioctl</STRONG> may be updated before creating each
+ <EM>screen</EM> rather than once only (<STRONG><A HREF="curs_sp_funcs.3x.html">curs_sp_funcs(3x)</A></STRONG>). This feature of
+ <STRONG>use_env</STRONG> is not provided by other implementations of curses.
+
+
+</PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE>
+ <STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG>, <STRONG><A HREF="curs_initscr.3x.html">curs_initscr(3x)</A></STRONG>, <STRONG><A HREF="curs_inopts.3x.html">curs_inopts(3x)</A></STRONG>, <STRONG><A HREF="curs_kernel.3x.html">curs_kernel(3x)</A></STRONG>,
+ <STRONG><A HREF="curs_scr_dump.3x.html">curs_scr_dump(3x)</A></STRONG>, <STRONG><A HREF="curs_sp_funcs.3x.html">curs_sp_funcs(3x)</A></STRONG>, <STRONG><A HREF="curs_variables.3x.html">curs_variables(3x)</A></STRONG>,
+ <STRONG><A HREF="legacy_coding.3x.html">legacy_coding(3x)</A></STRONG>
+
+
+
+ncurses 6.4 2023-10-14 <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>
</PRE>
-<HR>
-<ADDRESS>
-Man(1) output converted with
-<a href="http://www.oac.uci.edu/indiv/ehood/man2html.html">man2html</a>
-</ADDRESS>
+<div class="nav">
+<ul>
+<li><a href="#h2-NAME">NAME</a></li>
+<li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li>
+<li><a href="#h2-DESCRIPTION">DESCRIPTION</a>
+<ul>
+<li><a href="#h3-unctrl">unctrl</a></li>
+<li><a href="#h3-keyname_key_name">keyname/key_name</a></li>
+<li><a href="#h3-filter_nofilter">filter/nofilter</a></li>
+<li><a href="#h3-use_env">use_env</a></li>
+<li><a href="#h3-use_tioctl">use_tioctl</a></li>
+<li><a href="#h3-putwin_getwin">putwin/getwin</a></li>
+<li><a href="#h3-delay_output">delay_output</a></li>
+<li><a href="#h3-flushinp">flushinp</a></li>
+</ul>
+</li>
+<li><a href="#h2-RETURN-VALUE">RETURN VALUE</a></li>
+<li><a href="#h2-PORTABILITY">PORTABILITY</a>
+<ul>
+<li><a href="#h3-filter">filter</a></li>
+<li><a href="#h3-delay_output-padding">delay_output padding</a></li>
+<li><a href="#h3-keyname">keyname</a></li>
+<li><a href="#h3-nofilter_use_tioctl">nofilter/use_tioctl</a></li>
+<li><a href="#h3-putwin_getwin-file-format">putwin/getwin file-format</a></li>
+<li><a href="#h3-unctrl_wunctrl">unctrl/wunctrl</a></li>
+<li><a href="#h3-use_env_use_tioctl">use_env/use_tioctl</a></li>
+</ul>
+</li>
+<li><a href="#h2-SEE-ALSO">SEE ALSO</a></li>
+</ul>
+</div>
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