1 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN">
4 ****************************************************************************
5 * Copyright (c) 1998-2012,2013 Free Software Foundation, Inc. *
7 * Permission is hereby granted, free of charge, to any person obtaining a *
8 * copy of this software and associated documentation files (the *
9 * "Software"), to deal in the Software without restriction, including *
10 * without limitation the rights to use, copy, modify, merge, publish, *
11 * distribute, distribute with modifications, sublicense, and/or sell *
12 * copies of the Software, and to permit persons to whom the Software is *
13 * furnished to do so, subject to the following conditions: *
15 * The above copyright notice and this permission notice shall be included *
16 * in all copies or substantial portions of the Software. *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS *
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF *
20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. *
21 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, *
22 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR *
23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR *
24 * THE USE OR OTHER DEALINGS IN THE SOFTWARE. *
26 * Except as contained in this notice, the name(s) of the above copyright *
27 * holders shall not be used in advertising or otherwise to promote the *
28 * sale, use or other dealings in this Software without prior written *
30 ****************************************************************************
31 * @Id: curs_util.3x,v 1.37 2013/07/20 19:43:45 tom Exp @
35 <TITLE>curs_util 3x</TITLE>
36 <link rev=made href="mailto:bug-ncurses@gnu.org">
37 <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
43 <!-- Manpage converted by man2html 3.0.1 -->
44 <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG> <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>
51 <STRONG>delay_output</STRONG>, <STRONG>filter</STRONG>, <STRONG>flushinp</STRONG>, <STRONG>getwin</STRONG>, <STRONG>key_name</STRONG>, <STRONG>keyname</STRONG>,
52 <STRONG>nofilter</STRONG>, <STRONG>putwin</STRONG>, <STRONG>unctrl</STRONG>, <STRONG>use_env</STRONG>, <STRONG>use_tioctl</STRONG>, <STRONG>wunctrl</STRONG> -
53 miscellaneous <STRONG>curses</STRONG> utility routines
57 <H2>SYNOPSIS</H2><PRE>
58 <STRONG>#include</STRONG> <STRONG><curses.h></STRONG>
60 <STRONG>char</STRONG> <STRONG>*unctrl(chtype</STRONG> <STRONG>c);</STRONG>
61 <STRONG>wchar_t</STRONG> <STRONG>*wunctrl(cchar_t</STRONG> <STRONG>*c);</STRONG>
62 <STRONG>char</STRONG> <STRONG>*keyname(int</STRONG> <STRONG>c);</STRONG>
63 <STRONG>char</STRONG> <STRONG>*key_name(wchar_t</STRONG> <STRONG>w);</STRONG>
64 <STRONG>void</STRONG> <STRONG>filter(void);</STRONG>
65 <STRONG>void</STRONG> <STRONG>nofilter(void);</STRONG>
66 <STRONG>void</STRONG> <STRONG>use_env(bool</STRONG> <STRONG>f);</STRONG>
67 <STRONG>void</STRONG> <STRONG>use_tioctl(bool</STRONG> <STRONG>f);</STRONG>
68 <STRONG>int</STRONG> <STRONG>putwin(WINDOW</STRONG> <STRONG>*win,</STRONG> <STRONG>FILE</STRONG> <STRONG>*filep);</STRONG>
69 <STRONG>WINDOW</STRONG> <STRONG>*getwin(FILE</STRONG> <STRONG>*filep);</STRONG>
70 <STRONG>int</STRONG> <STRONG>delay_output(int</STRONG> <STRONG>ms);</STRONG>
71 <STRONG>int</STRONG> <STRONG>flushinp(void);</STRONG>
75 <H2>DESCRIPTION</H2><PRE>
76 The <STRONG>unctrl</STRONG> routine returns a character string which is a
77 printable representation of the character <EM>c</EM>, ignoring at-
78 tributes. Control characters are displayed in the <STRONG>^</STRONG><EM>X</EM> no-
79 tation. Printing characters are displayed as is. The
80 corresponding <STRONG>wunctrl</STRONG> returns a printable representation
83 The <STRONG>keyname</STRONG> routine returns a character string correspond-
84 ing to the key <EM>c</EM>:
86 <STRONG>o</STRONG> Printable characters are displayed as themselves,
87 e.g., a one-character string containing the key.
89 <STRONG>o</STRONG> Control characters are displayed in the <STRONG>^</STRONG><EM>X</EM> nota-
92 <STRONG>o</STRONG> DEL (character 127) is displayed as <STRONG>^?</STRONG>.
94 <STRONG>o</STRONG> Values above 128 are either meta characters (if the
95 screen has not been initialized, or if <STRONG>meta</STRONG> has
96 been called with a TRUE parameter), shown in the
97 <STRONG>M-</STRONG><EM>X</EM> notation, or are displayed as themselves. In
98 the latter case, the values may not be printable;
99 this follows the X/Open specification.
101 <STRONG>o</STRONG> Values above 256 may be the names of the names of
104 <STRONG>o</STRONG> Otherwise (if there is no corresponding name) the
105 function returns null, to denote an error. X/Open
106 also lists an "UNKNOWN KEY" return value, which
107 some implementations return rather than null.
109 The corresponding <STRONG>key_name</STRONG> returns a character string cor-
110 responding to the wide-character value <EM>w</EM>. The two func-
111 tions do not return the same set of strings; the latter
112 returns null where the former would display a meta charac-
115 The <STRONG>filter</STRONG> routine, if used, must be called before <STRONG>initscr</STRONG>
116 or <STRONG>newterm</STRONG> are called. The effect is that, during those
117 calls, <STRONG>LINES</STRONG> is set to 1; the capabilities <STRONG>clear</STRONG>, <STRONG>cup</STRONG>,
118 <STRONG>cud</STRONG>, <STRONG>cud1</STRONG>, <STRONG>cuu1</STRONG>, <STRONG>cuu</STRONG>, <STRONG>vpa</STRONG> are disabled; and the <STRONG>home</STRONG>
119 string is set to the value of <STRONG>cr</STRONG>.
121 The <STRONG>nofilter</STRONG> routine cancels the effect of a preceding
122 <STRONG>filter</STRONG> call. That allows the caller to initialize a
123 screen on a different device, using a different value of
124 <STRONG>$TERM</STRONG>. The limitation arises because the <STRONG>filter</STRONG> routine
125 modifies the in-memory copy of the terminal information.
127 The <STRONG>use_env</STRONG> routine, if used, should be called before
128 <STRONG>initscr</STRONG> or <STRONG>newterm</STRONG> are called (because those compute the
129 screen size). It modifies the way <STRONG>ncurses</STRONG> treats environ-
130 ment variables when determining the screen size.
132 <STRONG>o</STRONG> Normally ncurses looks first at the terminal database
135 If <STRONG>use_env</STRONG> was called with <STRONG>FALSE</STRONG> for parameter, it
136 stops here unless If <STRONG>use_tioctl</STRONG> was also called with
137 <STRONG>TRUE</STRONG> for parameter.
139 <STRONG>o</STRONG> Then it asks for the screen size via operating system
140 calls. If successful, it overrides the values from
141 the terminal database.
143 <STRONG>o</STRONG> Finally (unless <STRONG>use_env</STRONG> was called with <STRONG>FALSE</STRONG> parame-
144 ter), ncurses examines the <STRONG>LINES</STRONG> or <STRONG>COLUMNS</STRONG> environ-
145 ment variables, using a value in those to override the
146 results from the operating system or terminal data-
149 Ncurses also updates the screen size in response to
150 SIGWINCH, unless overridden by the <STRONG>LINES</STRONG> or <STRONG>COLUMNS</STRONG>
151 environment variables,
153 The <STRONG>use_tioctl</STRONG> routine, if used, should be called before
154 <STRONG>initscr</STRONG> or <STRONG>newterm</STRONG> are called (because those compute the
155 screen size). After <STRONG>use_tioctl</STRONG> is called with <STRONG>TRUE</STRONG> as an
156 argument, ncurses modifies the last step in its computa-
157 tion of screen size as follows:
159 <STRONG>o</STRONG> checks if the <STRONG>LINES</STRONG> and <STRONG>COLUMNS</STRONG> environment variables
160 are set to a number greater than zero.
162 <STRONG>o</STRONG> for each, ncurses updates the corresponding environ-
163 ment variable with the value that it has obtained via
164 operating system call or from the terminal database.
166 <STRONG>o</STRONG> ncurses re-fetches the value of the environment vari-
167 ables so that it is still the environment variables
168 which set the screen size.
170 The <STRONG>use_env</STRONG> and <STRONG>use_tioctl</STRONG> routines combine as summarized
173 <EM>use</EM><STRONG>_</STRONG><EM>env</EM> <EM>use</EM><STRONG>_</STRONG><EM>tioctl</EM> <EM>Summary</EM>
174 ----------------------------------------------------------------
175 TRUE FALSE This is the default behavior. ncurses
176 uses operating system calls unless over-
177 ridden by $LINES or $COLUMNS environment
179 TRUE TRUE ncurses updates $LINES and $COLUMNS
180 based on operating system calls.
182 FALSE TRUE ncurses ignores $LINES and $COLUMNS, us-
183 es operating system calls to obtain
185 FALSE FALSE ncurses relies on the terminal database
188 The <STRONG>putwin</STRONG> routine writes all data associated with window
189 <EM>win</EM> into the file to which <EM>filep</EM> points. This information
190 can be later retrieved using the <STRONG>getwin</STRONG> function.
192 The <STRONG>getwin</STRONG> routine reads window related data stored in the
193 file by <STRONG>putwin</STRONG>. The routine then creates and initializes
194 a new window using that data. It returns a pointer to the
197 The <STRONG>delay_output</STRONG> routine inserts an <EM>ms</EM> millisecond pause
198 in output. This routine should not be used extensively
199 because padding characters are used rather than a CPU
200 pause. If no padding character is specified, this uses
201 <STRONG>napms</STRONG> to perform the delay.
203 The <STRONG>flushinp</STRONG> routine throws away any typeahead that has
204 been typed by the user and has not yet been read by the
209 <H2>RETURN VALUE</H2><PRE>
210 Except for <STRONG>flushinp</STRONG>, routines that return an integer re-
211 turn <STRONG>ERR</STRONG> upon failure and <STRONG>OK</STRONG> (SVr4 specifies only "an in-
212 teger value other than <STRONG>ERR</STRONG>") upon successful completion.
214 Routines that return pointers return <STRONG>NULL</STRONG> on error.
216 X/Open does not define any error conditions. In this im-
219 <STRONG>flushinp</STRONG>
220 returns an error if the terminal was not initial-
223 <STRONG>meta</STRONG> returns an error if the terminal was not initial-
226 <STRONG>putwin</STRONG>
227 returns an error if the associated <STRONG>fwrite</STRONG> calls
232 <H2>PORTABILITY</H2><PRE>
233 The XSI Curses standard, Issue 4 describes these func-
234 tions. It states that <STRONG>unctrl</STRONG> and <STRONG>wunctrl</STRONG> will return a
235 null pointer if unsuccessful, but does not define any er-
236 ror conditions. This implementation checks for three cas-
239 <STRONG>o</STRONG> the parameter is a 7-bit US-ASCII code. This is
240 the case that X/Open Curses documented.
242 <STRONG>o</STRONG> the parameter is in the range 128-159, i.e., a C1
243 control code. If <STRONG>use_legacy_coding</STRONG> has been called
244 with a <STRONG>2</STRONG> parameter, <STRONG>unctrl</STRONG> returns the parameter,
245 i.e., a one-character string with the parameter as
246 the first character. Otherwise, it returns "~@",
247 "~A", etc., analogous to "^@", "^A", C0 controls.
249 X/Open Curses does not document whether <STRONG>unctrl</STRONG> can
250 be called before initializing curses. This imple-
251 mentation permits that, and returns the "~@", etc.,
254 <STRONG>o</STRONG> parameter values outside the 0 to 255 range. <STRONG>unc-</STRONG>
255 <STRONG>trl</STRONG> returns a null pointer.
257 The SVr4 documentation describes the action of <STRONG>filter</STRONG> only
258 in the vaguest terms. The description here is adapted
259 from the XSI Curses standard (which erroneously fails to
260 describe the disabling of <STRONG>cuu</STRONG>).
262 The strings returned by <STRONG>unctrl</STRONG> in this implementation are
263 determined at compile time, showing C1 controls from the
264 upper-128 codes with a `~' prefix rather than `^'. Other
265 implementations have different conventions. For example,
266 they may show both sets of control characters with `^',
267 and strip the parameter to 7 bits. Or they may ignore C1
268 controls and treat all of the upper-128 codes as print-
269 able. This implementation uses 8 bits but does not modify
270 the string to reflect locale. The <STRONG>use_legacy_coding</STRONG> func-
271 tion allows the caller to change the output of <STRONG>unctrl</STRONG>.
273 Likewise, the <STRONG>meta</STRONG> function allows the caller to change
274 the output of <STRONG>keyname</STRONG>, i.e., it determines whether to use
275 the `M-' prefix for "meta" keys (codes in the range 128 to
276 255). Both <STRONG>use_legacy_coding</STRONG> and <STRONG>meta</STRONG> succeed only after
277 curses is initialized. X/Open Curses does not document
278 the treatment of codes 128 to 159. When treating them as
279 "meta" keys (or if <STRONG>keyname</STRONG> is called before initializing
280 curses), this implementation returns strings "M-^@",
283 The <STRONG>keyname</STRONG> function may return the names of user-defined
284 string capabilities which are defined in the terminfo en-
285 try via the <STRONG>-x</STRONG> option of <STRONG>tic</STRONG>. This implementation auto-
286 matically assigns at run-time keycodes to user-defined
287 strings which begin with "k". The keycodes start at
288 KEY_MAX, but are not guaranteed to be the same value for
289 different runs because user-defined codes are merged from
290 all terminal descriptions which have been loaded. The
291 <STRONG>use_extended_names</STRONG> function controls whether this data is
292 loaded when the terminal description is read by the li-
295 The <STRONG>nofilter</STRONG> and <STRONG>use_tioctl</STRONG> routines are specific to
296 ncurses. They were not supported on Version 7, BSD or
297 System V implementations. It is recommended that any code
298 depending on ncurses extensions be conditioned using
303 <H2>SEE ALSO</H2><PRE>
304 <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>
305 <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>
306 <STRONG><A HREF="legacy_coding.3x.html">cy_coding(3x)</A></STRONG>.
310 <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>
314 Man(1) output converted with
315 <a href="http://www.oac.uci.edu/indiv/ehood/man2html.html">man2html</a>