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>
50 <H2><a name="h2-NAME">NAME</a></H2><PRE>
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><a name="h2-SYNOPSIS">SYNOPSIS</a></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><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
78 <H3><a name="h3-unctrl">unctrl</a></H3><PRE>
79 The <STRONG>unctrl</STRONG> routine returns a character string which is a
80 printable representation of the character <EM>c</EM>, ignoring at-
81 tributes. Control characters are displayed in the <STRONG>^</STRONG><EM>X</EM> no-
82 tation. Printing characters are displayed as is. The
83 corresponding <STRONG>wunctrl</STRONG> returns a printable representation
88 <H3><a name="h3-keyname_key_name">keyname/key_name</a></H3><PRE>
89 The <STRONG>keyname</STRONG> routine returns a character string correspond-
90 ing to the key <EM>c</EM>:
92 <STRONG>o</STRONG> Printable characters are displayed as themselves,
93 e.g., a one-character string containing the key.
95 <STRONG>o</STRONG> Control characters are displayed in the <STRONG>^</STRONG><EM>X</EM> notation.
97 <STRONG>o</STRONG> DEL (character 127) is displayed as <STRONG>^?</STRONG>.
99 <STRONG>o</STRONG> Values above 128 are either meta characters (if the
100 screen has not been initialized, or if <STRONG>meta</STRONG> has been
101 called with a <STRONG>TRUE</STRONG> parameter), shown in the <STRONG>M-</STRONG><EM>X</EM> nota-
102 tion, or are displayed as themselves. In the latter
103 case, the values may not be printable; this follows
104 the X/Open specification.
106 <STRONG>o</STRONG> Values above 256 may be the names of the names of
109 <STRONG>o</STRONG> Otherwise (if there is no corresponding name) the
110 function returns null, to denote an error. X/Open al-
111 so lists an "UNKNOWN KEY" return value, which some im-
112 plementations return rather than null.
114 The corresponding <STRONG>key_name</STRONG> returns a character string cor-
115 responding to the wide-character value <EM>w</EM>. The two func-
116 tions do not return the same set of strings; the latter
117 returns null where the former would display a meta charac-
122 <H3><a name="h3-filter_nofilter">filter/nofilter</a></H3><PRE>
123 The <STRONG>filter</STRONG> routine, if used, must be called before <STRONG>initscr</STRONG>
124 or <STRONG>newterm</STRONG> are called. The effect is that, during those
125 calls, <STRONG>LINES</STRONG> is set to 1; the capabilities <STRONG>clear</STRONG>, <STRONG>cup</STRONG>,
126 <STRONG>cud</STRONG>, <STRONG>cud1</STRONG>, <STRONG>cuu1</STRONG>, <STRONG>cuu</STRONG>, <STRONG>vpa</STRONG> are disabled; and the <STRONG>home</STRONG>
127 string is set to the value of <STRONG>cr</STRONG>.
129 The <STRONG>nofilter</STRONG> routine cancels the effect of a preceding
130 <STRONG>filter</STRONG> call. That allows the caller to initialize a
131 screen on a different device, using a different value of
132 <STRONG>$TERM</STRONG>. The limitation arises because the <STRONG>filter</STRONG> routine
133 modifies the in-memory copy of the terminal information.
137 <H3><a name="h3-use_env">use_env</a></H3><PRE>
138 The <STRONG>use_env</STRONG> routine, if used, should be called before
139 <STRONG>initscr</STRONG> or <STRONG>newterm</STRONG> are called (because those compute the
140 screen size). It modifies the way <STRONG>ncurses</STRONG> treats environ-
141 ment variables when determining the screen size.
143 <STRONG>o</STRONG> Normally ncurses looks first at the terminal database
146 If <STRONG>use_env</STRONG> was called with <STRONG>FALSE</STRONG> for parameter, it
147 stops here unless If <STRONG>use_tioctl</STRONG> was also called with
148 <STRONG>TRUE</STRONG> for parameter.
150 <STRONG>o</STRONG> Then it asks for the screen size via operating system
151 calls. If successful, it overrides the values from
152 the terminal database.
154 <STRONG>o</STRONG> Finally (unless <STRONG>use_env</STRONG> was called with <STRONG>FALSE</STRONG> parame-
155 ter), ncurses examines the <STRONG>LINES</STRONG> or <STRONG>COLUMNS</STRONG> environ-
156 ment variables, using a value in those to override the
157 results from the operating system or terminal data-
160 Ncurses also updates the screen size in response to
161 SIGWINCH, unless overridden by the <STRONG>LINES</STRONG> or <STRONG>COLUMNS</STRONG>
162 environment variables,
166 <H3><a name="h3-use_tioctl">use_tioctl</a></H3><PRE>
167 The <STRONG>use_tioctl</STRONG> routine, if used, should be called before
168 <STRONG>initscr</STRONG> or <STRONG>newterm</STRONG> are called (because those compute the
169 screen size). After <STRONG>use_tioctl</STRONG> is called with <STRONG>TRUE</STRONG> as an
170 argument, ncurses modifies the last step in its computa-
171 tion of screen size as follows:
173 <STRONG>o</STRONG> checks if the <STRONG>LINES</STRONG> and <STRONG>COLUMNS</STRONG> environment variables
174 are set to a number greater than zero.
176 <STRONG>o</STRONG> for each, ncurses updates the corresponding environ-
177 ment variable with the value that it has obtained via
178 operating system call or from the terminal database.
180 <STRONG>o</STRONG> ncurses re-fetches the value of the environment vari-
181 ables so that it is still the environment variables
182 which set the screen size.
184 The <STRONG>use_env</STRONG> and <STRONG>use_tioctl</STRONG> routines combine as summarized
187 <EM>use</EM><STRONG>_</STRONG><EM>env</EM> <EM>use</EM><STRONG>_</STRONG><EM>tioctl</EM> <EM>Summary</EM>
188 ----------------------------------------------------------------
192 TRUE FALSE This is the default behavior. ncurses
193 uses operating system calls unless over-
194 ridden by $LINES or $COLUMNS environment
196 TRUE TRUE ncurses updates $LINES and $COLUMNS
197 based on operating system calls.
198 FALSE TRUE ncurses ignores $LINES and $COLUMNS, us-
199 es operating system calls to obtain
201 FALSE FALSE ncurses relies on the terminal database
206 <H3><a name="h3-putwin_getwin">putwin/getwin</a></H3><PRE>
207 The <STRONG>putwin</STRONG> routine writes all data associated with window
208 (or pad) <EM>win</EM> into the file to which <EM>filep</EM> points. This
209 information can be later retrieved using the <STRONG>getwin</STRONG> func-
212 The <STRONG>getwin</STRONG> routine reads window related data stored in the
213 file by <STRONG>putwin</STRONG>. The routine then creates and initializes
214 a new window using that data. It returns a pointer to the
215 new window. There are a few caveats:
217 <STRONG>o</STRONG> the data written is a copy of the <STRONG>WINDOW</STRONG> structure,
218 and its associated character cells. The format dif-
219 fers between the wide-character (ncursesw) and non-
220 wide (ncurses) libraries. You can transfer data be-
221 tween the two, however.
223 <STRONG>o</STRONG> the retrieved window is always created as a top-level
224 window (or pad), rather than a subwindow.
226 <STRONG>o</STRONG> the window's character cells contain the color pair
227 <EM>value</EM>, but not the actual color <EM>numbers</EM>. If cells in
228 the retrieved window use color pairs which have not
229 been created in the application using <STRONG>init_pair</STRONG>, they
230 will not be colored when the window is refreshed.
234 <H3><a name="h3-delay_output">delay_output</a></H3><PRE>
235 The <STRONG>delay_output</STRONG> routine inserts an <EM>ms</EM> millisecond pause
236 in output. This routine should not be used extensively
237 because padding characters are used rather than a CPU
238 pause. If no padding character is specified, this uses
239 <STRONG>napms</STRONG> to perform the delay.
243 <H3><a name="h3-flushinp">flushinp</a></H3><PRE>
244 The <STRONG>flushinp</STRONG> routine throws away any typeahead that has
245 been typed by the user and has not yet been read by the
250 <H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
251 Except for <STRONG>flushinp</STRONG>, routines that return an integer re-
252 turn <STRONG>ERR</STRONG> upon failure and <STRONG>OK</STRONG> (SVr4 specifies only "an in-
253 teger value other than <STRONG>ERR</STRONG>") upon successful completion.
255 Routines that return pointers return <STRONG>NULL</STRONG> on error.
257 X/Open does not define any error conditions. In this im-
260 <STRONG>flushinp</STRONG>
261 returns an error if the terminal was not initial-
264 <STRONG>meta</STRONG> returns an error if the terminal was not initial-
267 <STRONG>putwin</STRONG>
268 returns an error if the associated <STRONG>fwrite</STRONG> calls
273 <H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
276 <H3><a name="h3-filter">filter</a></H3><PRE>
277 The SVr4 documentation describes the action of <STRONG>filter</STRONG> only
278 in the vaguest terms. The description here is adapted
279 from the XSI Curses standard (which erroneously fails to
280 describe the disabling of <STRONG>cuu</STRONG>).
284 <H3><a name="h3-keyname">keyname</a></H3><PRE>
285 The <STRONG>keyname</STRONG> function may return the names of user-defined
286 string capabilities which are defined in the terminfo en-
287 try via the <STRONG>-x</STRONG> option of <STRONG>tic</STRONG>. This implementation auto-
288 matically assigns at run-time keycodes to user-defined
289 strings which begin with "k". The keycodes start at
290 KEY_MAX, but are not guaranteed to be the same value for
291 different runs because user-defined codes are merged from
292 all terminal descriptions which have been loaded. The
293 <STRONG>use_extended_names</STRONG> function controls whether this data is
294 loaded when the terminal description is read by the li-
299 <H3><a name="h3-nofilter_use_tioctl">nofilter/use_tioctl</a></H3><PRE>
300 The <STRONG>nofilter</STRONG> and <STRONG>use_tioctl</STRONG> routines are specific to
301 ncurses. They were not supported on Version 7, BSD or
302 System V implementations. It is recommended that any code
303 depending on ncurses extensions be conditioned using
308 <H3><a name="h3-putwin_getwin">putwin/getwin</a></H3><PRE>
309 The <STRONG>putwin</STRONG> and <STRONG>getwin</STRONG> functions have several issues with
312 <STRONG>o</STRONG> The files written and read by these functions use an
313 implementation-specific format. Although the format
314 is an obvious target for standardization, it has been
317 Interestingly enough, according to the copyright dates
318 in Solaris source, the functions (along with <STRONG>scr_init</STRONG>,
319 etc.) originated with the University of California,
320 Berkeley (in 1982) and were later (in 1988) incorpo-
321 rated into SVr4. Oddly, there are no such functions
322 in the 4.3BSD curses sources.
324 <STRONG>o</STRONG> Most implementations simply dump the binary <STRONG>WINDOW</STRONG>
325 structure to the file. These include SVr4 curses,
326 NetBSD and PDCurses, as well as older ncurses ver-
327 sions. This implementation (as well as the X/Open
328 variant of Solaris curses, dated 1995) uses textual
331 The implementations which use binary dumps use block-
332 I/O (the <STRONG>fwrite</STRONG> and <STRONG>fread</STRONG> functions). Those that use
333 textual dumps use buffered-I/O. A few applications
334 may happen to write extra data in the file using these
335 functions. Doing that can run into problems mixing
336 block- and buffered-I/O. This implementation reduces
337 the problem on writes by flushing the output. Howev-
338 er, reading from a file written using mixed schemes
339 may not be successful.
343 <H3><a name="h3-unctrl_wunctrl">unctrl/wunctrl</a></H3><PRE>
344 The XSI Curses standard, Issue 4 describes these func-
345 tions. It states that <STRONG>unctrl</STRONG> and <STRONG>wunctrl</STRONG> will return a
346 null pointer if unsuccessful, but does not define any er-
347 ror conditions. This implementation checks for three cas-
350 <STRONG>o</STRONG> the parameter is a 7-bit US-ASCII code. This is the
351 case that X/Open Curses documented.
353 <STRONG>o</STRONG> the parameter is in the range 128-159, i.e., a C1 con-
354 trol code. If <STRONG>use_legacy_coding</STRONG> has been called with
355 a <STRONG>2</STRONG> parameter, <STRONG>unctrl</STRONG> returns the parameter, i.e., a
356 one-character string with the parameter as the first
357 character. Otherwise, it returns "~@", "~A", etc.,
358 analogous to "^@", "^A", C0 controls.
360 X/Open Curses does not document whether <STRONG>unctrl</STRONG> can be
361 called before initializing curses. This implementa-
362 tion permits that, and returns the "~@", etc., values
365 <STRONG>o</STRONG> parameter values outside the 0 to 255 range. <STRONG>unctrl</STRONG>
366 returns a null pointer.
368 The strings returned by <STRONG>unctrl</STRONG> in this implementation are
369 determined at compile time, showing C1 controls from the
370 upper-128 codes with a `~' prefix rather than `^'. Other
371 implementations have different conventions. For example,
372 they may show both sets of control characters with `^',
373 and strip the parameter to 7 bits. Or they may ignore C1
374 controls and treat all of the upper-128 codes as print-
375 able. This implementation uses 8 bits but does not modify
376 the string to reflect locale. The <STRONG>use_legacy_coding</STRONG> func-
377 tion allows the caller to change the output of <STRONG>unctrl</STRONG>.
379 Likewise, the <STRONG>meta</STRONG> function allows the caller to change
380 the output of <STRONG>keyname</STRONG>, i.e., it determines whether to use
381 the `M-' prefix for "meta" keys (codes in the range 128 to
382 255). Both <STRONG>use_legacy_coding</STRONG> and <STRONG>meta</STRONG> succeed only after
383 curses is initialized. X/Open Curses does not document
384 the treatment of codes 128 to 159. When treating them as
385 "meta" keys (or if <STRONG>keyname</STRONG> is called before initializing
386 curses), this implementation returns strings "M-^@",
391 <H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE>
392 <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>
393 <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>
394 <STRONG><A HREF="legacy_coding.3x.html">cy_coding(3x)</A></STRONG>.
398 <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>
402 <li><a href="#h2-NAME">NAME</a></li>
403 <li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li>
404 <li><a href="#h2-DESCRIPTION">DESCRIPTION</a>
406 <li><a href="#h3-unctrl">unctrl</a></li>
407 <li><a href="#h3-keyname_key_name">keyname/key_name</a></li>
408 <li><a href="#h3-filter_nofilter">filter/nofilter</a></li>
409 <li><a href="#h3-use_env">use_env</a></li>
410 <li><a href="#h3-use_tioctl">use_tioctl</a></li>
411 <li><a href="#h3-putwin_getwin">putwin/getwin</a></li>
412 <li><a href="#h3-delay_output">delay_output</a></li>
413 <li><a href="#h3-flushinp">flushinp</a></li>
416 <li><a href="#h2-RETURN-VALUE">RETURN VALUE</a></li>
417 <li><a href="#h2-PORTABILITY">PORTABILITY</a>
419 <li><a href="#h3-filter">filter</a></li>
420 <li><a href="#h3-keyname">keyname</a></li>
421 <li><a href="#h3-nofilter_use_tioctl">nofilter/use_tioctl</a></li>
422 <li><a href="#h3-putwin_getwin">putwin/getwin</a></li>
423 <li><a href="#h3-unctrl_wunctrl">unctrl/wunctrl</a></li>
426 <li><a href="#h2-SEE-ALSO">SEE ALSO</a></li>