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</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
+ <STRONG>nofilter</STRONG>, <STRONG>putwin</STRONG>, <STRONG>unctrl</STRONG>, <STRONG>use_env</STRONG>, <STRONG>use_tioctl</STRONG>, <STRONG>wunctrl</STRONG> -
+ miscellaneous <STRONG>curses</STRONG> utility routines
</PRE>
<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>void</STRONG> <STRONG>use_tioctl(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>
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.
+ 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.
+ <STRONG>o</STRONG> 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.
+ <STRONG>o</STRONG> Control characters are displayed in the <STRONG>^</STRONG><EM>X</EM> nota-
+ tion.
- - DEL (character 127) is displayed as <STRONG>^?</STRONG>.
+ <STRONG>o</STRONG> 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.
+ <STRONG>o</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> notation, or are displayed as themselves. In
+ the latter case, the values may not be printable;
+ this follows the X/Open specification.
- - Values above 256 may be the names of the names of
- function keys.
+ <STRONG>o</STRONG> 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.
+ <STRONG>o</STRONG> 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
+ 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>
+ 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>$TERM</STRONG>. The limitation arises because the <STRONG>filter</STRONG> routine
+ The <STRONG>nofilter</STRONG> routine cancels the effect of a preceding
+ <STRONG>filter</STRONG> call. That allows the caller to initialize a
+ screen on a different device, using a different value of
+ <STRONG>$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
+ 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 <STRONG>ncurses</STRONG> treats environ-
+ ment variables when determining the screen size.
+
+ <STRONG>o</STRONG> Normally ncurses 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 If <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> parame-
+ ter), ncurses examines the <STRONG>LINES</STRONG> or <STRONG>COLUMNS</STRONG> environ-
+ ment variables, using a value in those to override the
+ results from the operating system or terminal data-
+ base.
+
+ Ncurses also updates the screen size in response to
+ SIGWINCH, unless overridden by the <STRONG>LINES</STRONG> or <STRONG>COLUMNS</STRONG>
+ environment variables,
+
+ 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, ncurses modifies the last step in its computa-
+ tion 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, ncurses updates the corresponding environ-
+ ment variable with the value that it has obtained via
+ operating system call or from the terminal database.
+
+ <STRONG>o</STRONG> ncurses re-fetches the value of the environment vari-
+ ables 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 summarized
+ here:
+
+ <EM>use</EM><STRONG>_</STRONG><EM>env</EM> <EM>use</EM><STRONG>_</STRONG><EM>tioctl</EM> <EM>Summary</EM>
+ ----------------------------------------------------------------
+ TRUE FALSE This is the default behavior. ncurses
+ uses operating system calls unless over-
+ ridden by $LINES or $COLUMNS environment
+ variables.
+ TRUE TRUE ncurses updates $LINES and $COLUMNS
+ based on operating system calls.
+
+ FALSE TRUE ncurses ignores $LINES and $COLUMNS, us-
+ es operating system calls to obtain
+ size.
+ FALSE FALSE ncurses relies on the terminal database
+ to determine size.
+
+ 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
+ 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
+ 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
+ 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>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-
+ 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.
Routines that return pointers return <STRONG>NULL</STRONG> on error.
- X/Open does not define any error conditions. In this im-
+ X/Open does not define any error conditions. In this im-
plementation
<STRONG>flushinp</STRONG>
- returns an error if the terminal was not initial-
+ returns an error if the terminal was not initial-
ized.
- <STRONG>meta</STRONG> returns an error if the terminal was not initial-
+ <STRONG>meta</STRONG> returns an error if the terminal was not initial-
ized.
<STRONG>putwin</STRONG>
- returns an error if the associated <STRONG>fwrite</STRONG> calls
+ 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-
+ 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.
+ <STRONG>o</STRONG> 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.
+ <STRONG>o</STRONG> 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.
+ X/Open Curses does not document whether <STRONG>unctrl</STRONG> can
+ be called before initializing curses. This imple-
+ mentation 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.
+ <STRONG>o</STRONG> parameter values outside the 0 to 255 range. <STRONG>unc-</STRONG>
+ <STRONG>trl</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
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 `M-' prefix for "meta" keys (codes in the range 128 to
+ 255). Both <STRONG>use_legacy_coding</STRONG> and <STRONG>meta</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.
The <STRONG>keyname</STRONG> function may return the names of user-defined
string capabilities which are defined in the terminfo en-
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.
+ The <STRONG>nofilter</STRONG> and <STRONG>use_tioctl</STRONG> routines are specific to
+ ncurses. They were not supported on Version 7, BSD or
+ System V implementations. It is recommended that any code
+ depending on ncurses extensions be conditioned using
+ NCURSES_VERSION.
</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><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="curs_variables.3x.html">curs_variables(3x)</A></STRONG>, <STRONG>lega-</STRONG>
+ <STRONG><A HREF="legacy_coding.3x.html">cy_coding(3x)</A></STRONG>.