3 ****************************************************************************
4 * Copyright (c) 1998-2013,2015 Free Software Foundation, Inc. *
6 * Permission is hereby granted, free of charge, to any person obtaining a *
7 * copy of this software and associated documentation files (the *
8 * "Software"), to deal in the Software without restriction, including *
9 * without limitation the rights to use, copy, modify, merge, publish, *
10 * distribute, distribute with modifications, sublicense, and/or sell *
11 * copies of the Software, and to permit persons to whom the Software is *
12 * furnished to do so, subject to the following conditions: *
14 * The above copyright notice and this permission notice shall be included *
15 * in all copies or substantial portions of the Software. *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS *
18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF *
19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. *
20 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, *
21 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR *
22 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR *
23 * THE USE OR OTHER DEALINGS IN THE SOFTWARE. *
25 * Except as contained in this notice, the name(s) of the above copyright *
26 * holders shall not be used in advertising or otherwise to promote the *
27 * sale, use or other dealings in this Software without prior written *
29 ****************************************************************************
30 * @Id: curs_util.3x,v 1.43 2015/06/06 23:36:27 tom Exp @
32 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN">
35 <meta http-equiv="Content-Type" content="text/html; charset=us-ascii">
36 <meta name="generator" content="Manpage converted by man2html - see http://invisible-island.net/scripts/readme.html#others_scripts">
37 <TITLE>curs_util 3x</TITLE>
38 <link rev=made href="mailto:bug-ncurses@gnu.org">
39 <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
42 <H1 class="no-header">curs_util 3x</H1>
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>
49 </PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
50 <STRONG>delay_output</STRONG>, <STRONG>filter</STRONG>, <STRONG>flushinp</STRONG>, <STRONG>getwin</STRONG>, <STRONG>key_name</STRONG>, <STRONG>keyname</STRONG>,
51 <STRONG>nofilter</STRONG>, <STRONG>putwin</STRONG>, <STRONG>unctrl</STRONG>, <STRONG>use_env</STRONG>, <STRONG>use_tioctl</STRONG>, <STRONG>wunctrl</STRONG> -
52 miscellaneous <STRONG>curses</STRONG> utility routines
55 </PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
56 <STRONG>#include</STRONG> <STRONG><curses.h></STRONG>
58 <STRONG>char</STRONG> <STRONG>*unctrl(chtype</STRONG> <STRONG>c);</STRONG>
59 <STRONG>wchar_t</STRONG> <STRONG>*wunctrl(cchar_t</STRONG> <STRONG>*c);</STRONG>
60 <STRONG>char</STRONG> <STRONG>*keyname(int</STRONG> <STRONG>c);</STRONG>
61 <STRONG>char</STRONG> <STRONG>*key_name(wchar_t</STRONG> <STRONG>w);</STRONG>
62 <STRONG>void</STRONG> <STRONG>filter(void);</STRONG>
63 <STRONG>void</STRONG> <STRONG>nofilter(void);</STRONG>
64 <STRONG>void</STRONG> <STRONG>use_env(bool</STRONG> <STRONG>f);</STRONG>
65 <STRONG>void</STRONG> <STRONG>use_tioctl(bool</STRONG> <STRONG>f);</STRONG>
66 <STRONG>int</STRONG> <STRONG>putwin(WINDOW</STRONG> <STRONG>*win,</STRONG> <STRONG>FILE</STRONG> <STRONG>*filep);</STRONG>
67 <STRONG>WINDOW</STRONG> <STRONG>*getwin(FILE</STRONG> <STRONG>*filep);</STRONG>
68 <STRONG>int</STRONG> <STRONG>delay_output(int</STRONG> <STRONG>ms);</STRONG>
69 <STRONG>int</STRONG> <STRONG>flushinp(void);</STRONG>
72 </PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
74 </PRE><H3><a name="h3-unctrl">unctrl</a></H3><PRE>
75 The <STRONG>unctrl</STRONG> routine returns a character string which is a
76 printable representation of the character <EM>c</EM>, ignoring at-
77 tributes. Control characters are displayed in the <STRONG>^</STRONG><EM>X</EM> no-
78 tation. Printing characters are displayed as is. The
79 corresponding <STRONG>wunctrl</STRONG> returns a printable representation
83 </PRE><H3><a name="h3-keyname_key_name">keyname/key_name</a></H3><PRE>
84 The <STRONG>keyname</STRONG> routine returns a character string correspond-
85 ing to the key <EM>c</EM>:
87 <STRONG>o</STRONG> Printable characters are displayed as themselves,
88 e.g., a one-character string containing the key.
90 <STRONG>o</STRONG> Control characters are displayed in the <STRONG>^</STRONG><EM>X</EM> notation.
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 been
96 called with a <STRONG>TRUE</STRONG> parameter), shown in the <STRONG>M-</STRONG><EM>X</EM> nota-
97 tion, or are displayed as themselves. In the latter
98 case, the values may not be printable; this follows
99 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 al-
106 so lists an "UNKNOWN KEY" return value, which some im-
107 plementations 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-
116 </PRE><H3><a name="h3-filter_nofilter">filter/nofilter</a></H3><PRE>
117 The <STRONG>filter</STRONG> routine, if used, must be called before <STRONG>initscr</STRONG>
118 or <STRONG>newterm</STRONG> are called. The effect is that, during those
119 calls, <STRONG>LINES</STRONG> is set to 1; the capabilities <STRONG>clear</STRONG>, <STRONG>cup</STRONG>,
120 <STRONG>cud</STRONG>, <STRONG>cud1</STRONG>, <STRONG>cuu1</STRONG>, <STRONG>cuu</STRONG>, <STRONG>vpa</STRONG> are disabled; and the <STRONG>home</STRONG>
121 string is set to the value of <STRONG>cr</STRONG>.
123 The <STRONG>nofilter</STRONG> routine cancels the effect of a preceding
124 <STRONG>filter</STRONG> call. That allows the caller to initialize a
125 screen on a different device, using a different value of
126 <STRONG>$TERM</STRONG>. The limitation arises because the <STRONG>filter</STRONG> routine
127 modifies the in-memory copy of the terminal information.
130 </PRE><H3><a name="h3-use_env">use_env</a></H3><PRE>
131 The <STRONG>use_env</STRONG> routine, if used, should be called before
132 <STRONG>initscr</STRONG> or <STRONG>newterm</STRONG> are called (because those compute the
133 screen size). It modifies the way <STRONG>ncurses</STRONG> treats environ-
134 ment variables when determining the screen size.
136 <STRONG>o</STRONG> Normally ncurses looks first at the terminal database
139 If <STRONG>use_env</STRONG> was called with <STRONG>FALSE</STRONG> for parameter, it
140 stops here unless If <STRONG>use_tioctl</STRONG> was also called with
141 <STRONG>TRUE</STRONG> for parameter.
143 <STRONG>o</STRONG> Then it asks for the screen size via operating system
144 calls. If successful, it overrides the values from
145 the terminal database.
147 <STRONG>o</STRONG> Finally (unless <STRONG>use_env</STRONG> was called with <STRONG>FALSE</STRONG> parame-
148 ter), ncurses examines the <STRONG>LINES</STRONG> or <STRONG>COLUMNS</STRONG> environ-
149 ment variables, using a value in those to override the
150 results from the operating system or terminal data-
153 Ncurses also updates the screen size in response to
154 SIGWINCH, unless overridden by the <STRONG>LINES</STRONG> or <STRONG>COLUMNS</STRONG>
155 environment variables,
158 </PRE><H3><a name="h3-use_tioctl">use_tioctl</a></H3><PRE>
159 The <STRONG>use_tioctl</STRONG> routine, if used, should be called before
160 <STRONG>initscr</STRONG> or <STRONG>newterm</STRONG> are called (because those compute the
161 screen size). After <STRONG>use_tioctl</STRONG> is called with <STRONG>TRUE</STRONG> as an
162 argument, ncurses modifies the last step in its computa-
163 tion of screen size as follows:
165 <STRONG>o</STRONG> checks if the <STRONG>LINES</STRONG> and <STRONG>COLUMNS</STRONG> environment variables
166 are set to a number greater than zero.
168 <STRONG>o</STRONG> for each, ncurses updates the corresponding environ-
169 ment variable with the value that it has obtained via
170 operating system call or from the terminal database.
172 <STRONG>o</STRONG> ncurses re-fetches the value of the environment vari-
173 ables so that it is still the environment variables
174 which set the screen size.
176 The <STRONG>use_env</STRONG> and <STRONG>use_tioctl</STRONG> routines combine as summarized
179 <EM>use</EM><STRONG>_</STRONG><EM>env</EM> <EM>use</EM><STRONG>_</STRONG><EM>tioctl</EM> <EM>Summary</EM>
180 ----------------------------------------------------------------
184 TRUE FALSE This is the default behavior. ncurses
185 uses operating system calls unless over-
186 ridden by $LINES or $COLUMNS environment
188 TRUE TRUE ncurses updates $LINES and $COLUMNS
189 based on operating system calls.
190 FALSE TRUE ncurses ignores $LINES and $COLUMNS, us-
191 es operating system calls to obtain
193 FALSE FALSE ncurses relies on the terminal database
197 </PRE><H3><a name="h3-putwin_getwin">putwin/getwin</a></H3><PRE>
198 The <STRONG>putwin</STRONG> routine writes all data associated with window
199 (or pad) <EM>win</EM> into the file to which <EM>filep</EM> points. This
200 information can be later retrieved using the <STRONG>getwin</STRONG> func-
203 The <STRONG>getwin</STRONG> routine reads window related data stored in the
204 file by <STRONG>putwin</STRONG>. The routine then creates and initializes
205 a new window using that data. It returns a pointer to the
206 new window. There are a few caveats:
208 <STRONG>o</STRONG> the data written is a copy of the <STRONG>WINDOW</STRONG> structure,
209 and its associated character cells. The format dif-
210 fers between the wide-character (ncursesw) and non-
211 wide (ncurses) libraries. You can transfer data be-
212 tween the two, however.
214 <STRONG>o</STRONG> the retrieved window is always created as a top-level
215 window (or pad), rather than a subwindow.
217 <STRONG>o</STRONG> the window's character cells contain the color pair
218 <EM>value</EM>, but not the actual color <EM>numbers</EM>. If cells in
219 the retrieved window use color pairs which have not
220 been created in the application using <STRONG>init_pair</STRONG>, they
221 will not be colored when the window is refreshed.
224 </PRE><H3><a name="h3-delay_output">delay_output</a></H3><PRE>
225 The <STRONG>delay_output</STRONG> routine inserts an <EM>ms</EM> millisecond pause
226 in output. This routine should not be used extensively
227 because padding characters are used rather than a CPU
228 pause. If no padding character is specified, this uses
229 <STRONG>napms</STRONG> to perform the delay.
232 </PRE><H3><a name="h3-flushinp">flushinp</a></H3><PRE>
233 The <STRONG>flushinp</STRONG> routine throws away any typeahead that has
234 been typed by the user and has not yet been read by the
238 </PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
239 Except for <STRONG>flushinp</STRONG>, routines that return an integer re-
240 turn <STRONG>ERR</STRONG> upon failure and <STRONG>OK</STRONG> (SVr4 specifies only "an in-
241 teger value other than <STRONG>ERR</STRONG>") upon successful completion.
243 Routines that return pointers return <STRONG>NULL</STRONG> on error.
245 X/Open does not define any error conditions. In this im-
248 <STRONG>flushinp</STRONG>
249 returns an error if the terminal was not initial-
252 <STRONG>meta</STRONG> returns an error if the terminal was not initial-
255 <STRONG>putwin</STRONG>
256 returns an error if the associated <STRONG>fwrite</STRONG> calls
260 </PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
262 </PRE><H3><a name="h3-filter">filter</a></H3><PRE>
263 The SVr4 documentation describes the action of <STRONG>filter</STRONG> only
264 in the vaguest terms. The description here is adapted
265 from the XSI Curses standard (which erroneously fails to
266 describe the disabling of <STRONG>cuu</STRONG>).
269 </PRE><H3><a name="h3-keyname">keyname</a></H3><PRE>
270 The <STRONG>keyname</STRONG> function may return the names of user-defined
271 string capabilities which are defined in the terminfo en-
272 try via the <STRONG>-x</STRONG> option of <STRONG>tic</STRONG>. This implementation auto-
273 matically assigns at run-time keycodes to user-defined
274 strings which begin with "k". The keycodes start at
275 KEY_MAX, but are not guaranteed to be the same value for
276 different runs because user-defined codes are merged from
277 all terminal descriptions which have been loaded. The
278 <STRONG>use_extended_names</STRONG> function controls whether this data is
279 loaded when the terminal description is read by the li-
283 </PRE><H3><a name="h3-nofilter_use_tioctl">nofilter/use_tioctl</a></H3><PRE>
284 The <STRONG>nofilter</STRONG> and <STRONG>use_tioctl</STRONG> routines are specific to
285 ncurses. They were not supported on Version 7, BSD or
286 System V implementations. It is recommended that any code
287 depending on ncurses extensions be conditioned using
291 </PRE><H3><a name="h3-putwin_getwin">putwin/getwin</a></H3><PRE>
292 The <STRONG>putwin</STRONG> and <STRONG>getwin</STRONG> functions have several issues with
295 <STRONG>o</STRONG> The files written and read by these functions use an
296 implementation-specific format. Although the format
297 is an obvious target for standardization, it has been
300 Interestingly enough, according to the copyright dates
301 in Solaris source, the functions (along with <STRONG>scr_init</STRONG>,
302 etc.) originated with the University of California,
303 Berkeley (in 1982) and were later (in 1988) incorpo-
304 rated into SVr4. Oddly, there are no such functions
305 in the 4.3BSD curses sources.
307 <STRONG>o</STRONG> Most implementations simply dump the binary <STRONG>WINDOW</STRONG>
308 structure to the file. These include SVr4 curses,
309 NetBSD and PDCurses, as well as older ncurses ver-
310 sions. This implementation (as well as the X/Open
311 variant of Solaris curses, dated 1995) uses textual
314 The implementations which use binary dumps use block-
315 I/O (the <STRONG>fwrite</STRONG> and <STRONG>fread</STRONG> functions). Those that use
316 textual dumps use buffered-I/O. A few applications
317 may happen to write extra data in the file using these
318 functions. Doing that can run into problems mixing
319 block- and buffered-I/O. This implementation reduces
320 the problem on writes by flushing the output. Howev-
321 er, reading from a file written using mixed schemes
322 may not be successful.
325 </PRE><H3><a name="h3-unctrl_wunctrl">unctrl/wunctrl</a></H3><PRE>
326 The XSI Curses standard, Issue 4 describes these func-
327 tions. It states that <STRONG>unctrl</STRONG> and <STRONG>wunctrl</STRONG> will return a
328 null pointer if unsuccessful, but does not define any er-
329 ror conditions. This implementation checks for three cas-
332 <STRONG>o</STRONG> the parameter is a 7-bit US-ASCII code. This is the
333 case that X/Open Curses documented.
335 <STRONG>o</STRONG> the parameter is in the range 128-159, i.e., a C1 con-
336 trol code. If <STRONG>use_legacy_coding</STRONG> has been called with
337 a <STRONG>2</STRONG> parameter, <STRONG>unctrl</STRONG> returns the parameter, i.e., a
338 one-character string with the parameter as the first
339 character. Otherwise, it returns "~@", "~A", etc.,
340 analogous to "^@", "^A", C0 controls.
342 X/Open Curses does not document whether <STRONG>unctrl</STRONG> can be
343 called before initializing curses. This implementa-
344 tion permits that, and returns the "~@", etc., values
347 <STRONG>o</STRONG> parameter values outside the 0 to 255 range. <STRONG>unctrl</STRONG>
348 returns a null pointer.
350 The strings returned by <STRONG>unctrl</STRONG> in this implementation are
351 determined at compile time, showing C1 controls from the
352 upper-128 codes with a `~' prefix rather than `^'. Other
353 implementations have different conventions. For example,
354 they may show both sets of control characters with `^',
355 and strip the parameter to 7 bits. Or they may ignore C1
356 controls and treat all of the upper-128 codes as print-
357 able. This implementation uses 8 bits but does not modify
358 the string to reflect locale. The <STRONG>use_legacy_coding</STRONG> func-
359 tion allows the caller to change the output of <STRONG>unctrl</STRONG>.
361 Likewise, the <STRONG>meta</STRONG> function allows the caller to change
362 the output of <STRONG>keyname</STRONG>, i.e., it determines whether to use
363 the `M-' prefix for "meta" keys (codes in the range 128 to
364 255). Both <STRONG>use_legacy_coding</STRONG> and <STRONG>meta</STRONG> succeed only after
365 curses is initialized. X/Open Curses does not document
366 the treatment of codes 128 to 159. When treating them as
367 "meta" keys (or if <STRONG>keyname</STRONG> is called before initializing
368 curses), this implementation returns strings "M-^@",
372 </PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE>
373 <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>
374 <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>
375 <STRONG><A HREF="legacy_coding.3x.html">cy_coding(3x)</A></STRONG>.
379 <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>
383 <li><a href="#h2-NAME">NAME</a></li>
384 <li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li>
385 <li><a href="#h2-DESCRIPTION">DESCRIPTION</a>
387 <li><a href="#h3-unctrl">unctrl</a></li>
388 <li><a href="#h3-keyname_key_name">keyname/key_name</a></li>
389 <li><a href="#h3-filter_nofilter">filter/nofilter</a></li>
390 <li><a href="#h3-use_env">use_env</a></li>
391 <li><a href="#h3-use_tioctl">use_tioctl</a></li>
392 <li><a href="#h3-putwin_getwin">putwin/getwin</a></li>
393 <li><a href="#h3-delay_output">delay_output</a></li>
394 <li><a href="#h3-flushinp">flushinp</a></li>
397 <li><a href="#h2-RETURN-VALUE">RETURN VALUE</a></li>
398 <li><a href="#h2-PORTABILITY">PORTABILITY</a>
400 <li><a href="#h3-filter">filter</a></li>
401 <li><a href="#h3-keyname">keyname</a></li>
402 <li><a href="#h3-nofilter_use_tioctl">nofilter/use_tioctl</a></li>
403 <li><a href="#h3-putwin_getwin">putwin/getwin</a></li>
404 <li><a href="#h3-unctrl_wunctrl">unctrl/wunctrl</a></li>
407 <li><a href="#h2-SEE-ALSO">SEE ALSO</a></li>