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43 <H1 class="no-header">curs_util 3x</H1>
45 <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 </PRE><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>, <STRONG>nofilter</STRONG>,
52 <STRONG>putwin</STRONG>, <STRONG>unctrl</STRONG>, <STRONG>use_env</STRONG>, <STRONG>use_tioctl</STRONG>, <STRONG>wunctrl</STRONG> - miscellaneous <STRONG>curses</STRONG>
56 </PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
57 <STRONG>#include</STRONG> <STRONG><curses.h></STRONG>
59 <STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*unctrl(chtype</STRONG> <EM>c</EM><STRONG>);</STRONG>
60 <STRONG>wchar_t</STRONG> <STRONG>*wunctrl(cchar_t</STRONG> <STRONG>*</STRONG><EM>c</EM><STRONG>);</STRONG>
62 <STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*keyname(int</STRONG> <EM>c</EM><STRONG>);</STRONG>
63 <STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*key_name(wchar_t</STRONG> <EM>w</EM><STRONG>);</STRONG>
65 <STRONG>void</STRONG> <STRONG>filter(void);</STRONG>
66 <STRONG>void</STRONG> <STRONG>nofilter(void);</STRONG>
68 <STRONG>void</STRONG> <STRONG>use_env(bool</STRONG> <EM>f</EM><STRONG>);</STRONG>
69 <STRONG>void</STRONG> <STRONG>use_tioctl(bool</STRONG> <EM>f</EM><STRONG>);</STRONG>
71 <STRONG>int</STRONG> <STRONG>putwin(WINDOW</STRONG> <STRONG>*</STRONG><EM>win</EM><STRONG>,</STRONG> <STRONG>FILE</STRONG> <STRONG>*</STRONG><EM>filep</EM><STRONG>);</STRONG>
72 <STRONG>WINDOW</STRONG> <STRONG>*getwin(FILE</STRONG> <STRONG>*</STRONG><EM>filep</EM><STRONG>);</STRONG>
74 <STRONG>int</STRONG> <STRONG>delay_output(int</STRONG> <EM>ms</EM><STRONG>);</STRONG>
75 <STRONG>int</STRONG> <STRONG>flushinp(void);</STRONG>
78 </PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
80 </PRE><H3><a name="h3-unctrl">unctrl</a></H3><PRE>
81 The <STRONG>unctrl</STRONG> routine returns a character string which is a printable rep-
82 resentation of the character <EM>c</EM>, ignoring attributes. Control charac-
83 ters are displayed in the <STRONG>^</STRONG><EM>X</EM> notation. Printing characters are dis-
86 The corresponding <STRONG>wunctrl</STRONG> returns a printable representation of a wide
90 </PRE><H3><a name="h3-keyname_key_name">keyname/key_name</a></H3><PRE>
91 The <STRONG>keyname</STRONG> routine returns a character string corresponding to the key
94 <STRONG>o</STRONG> Printable characters are displayed as themselves, e.g., a one-char-
95 acter string containing the key.
97 <STRONG>o</STRONG> Control characters are displayed in the <STRONG>^</STRONG><EM>X</EM> notation.
99 <STRONG>o</STRONG> DEL (character 127) is displayed as <STRONG>^?</STRONG>.
101 <STRONG>o</STRONG> Values above 128 are either meta characters (if the screen has not
102 been initialized, or if <STRONG><A HREF="curs_inopts.3x.html">meta(3x)</A></STRONG> has been called with a <STRONG>TRUE</STRONG> param-
103 eter), shown in the <STRONG>M-</STRONG><EM>X</EM> notation, or are displayed as themselves.
104 In the latter case, the values may not be printable; this follows
105 the X/Open specification.
107 <STRONG>o</STRONG> Values above 256 may be the names of the names of function keys.
109 <STRONG>o</STRONG> Otherwise (if there is no corresponding name) the function returns
110 null, to denote an error. X/Open also lists an "UNKNOWN KEY" re-
111 turn value, which some implementations return rather than null.
113 The corresponding <STRONG>key_name</STRONG> returns a character string corresponding to
114 the wide-character value <EM>w</EM>. The two functions do not return the same
115 set of strings; the latter returns null where the former would display
119 </PRE><H3><a name="h3-filter_nofilter">filter/nofilter</a></H3><PRE>
120 The <STRONG>filter</STRONG> routine, if used, must be called before <STRONG>initscr</STRONG> or <STRONG>newterm</STRONG>
121 are called. Calling <STRONG>filter</STRONG> causes these changes in initialization:
123 <STRONG>o</STRONG> <STRONG>LINES</STRONG> is set to 1;
125 <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 dis-
128 <STRONG>o</STRONG> the capability <STRONG>ed</STRONG> is disabled if <STRONG>bce</STRONG> is set;
130 <STRONG>o</STRONG> and the <STRONG>home</STRONG> string is set to the value of <STRONG>cr</STRONG>.
132 The <STRONG>nofilter</STRONG> routine cancels the effect of a preceding <STRONG>filter</STRONG> call.
133 That allows the caller to initialize a screen on a different device,
134 using a different value of <STRONG>$TERM</STRONG>. The limitation arises because the
135 <STRONG>filter</STRONG> routine modifies the in-memory copy of the terminal information.
138 </PRE><H3><a name="h3-use_env">use_env</a></H3><PRE>
139 The <STRONG>use_env</STRONG> routine, if used, should be called before <STRONG>initscr</STRONG> or
140 <STRONG>newterm</STRONG> are called (because those compute the screen size). It modi-
141 fies the way <STRONG>ncurses</STRONG> treats environment variables when determining the
144 <STRONG>o</STRONG> Normally <STRONG>ncurses</STRONG> looks first at the terminal database for the
147 If <STRONG>use_env</STRONG> was called with <STRONG>FALSE</STRONG> for parameter, it stops here un-
148 less <STRONG>use_tioctl</STRONG> was also called with <STRONG>TRUE</STRONG> for parameter.
150 <STRONG>o</STRONG> Then it asks for the screen size via operating system calls. If
151 successful, it overrides the values from the terminal database.
153 <STRONG>o</STRONG> Finally (unless <STRONG>use_env</STRONG> was called with <STRONG>FALSE</STRONG> parameter), <STRONG>ncurses</STRONG>
154 examines the <STRONG>LINES</STRONG> or <STRONG>COLUMNS</STRONG> environment variables, using a value
155 in those to override the results from the operating system or ter-
158 <STRONG>Ncurses</STRONG> also updates the screen size in response to <STRONG>SIGWINCH</STRONG>, un-
159 less overridden by the <STRONG>LINES</STRONG> or <STRONG>COLUMNS</STRONG> environment variables,
162 </PRE><H3><a name="h3-use_tioctl">use_tioctl</a></H3><PRE>
163 The <STRONG>use_tioctl</STRONG> routine, if used, should be called before <STRONG>initscr</STRONG> or
164 <STRONG>newterm</STRONG> are called (because those compute the screen size). After
165 <STRONG>use_tioctl</STRONG> is called with <STRONG>TRUE</STRONG> as an argument, <STRONG>ncurses</STRONG> modifies the
166 last step in its computation of screen size as follows:
168 <STRONG>o</STRONG> checks if the <STRONG>LINES</STRONG> and <STRONG>COLUMNS</STRONG> environment variables are set to a
169 number greater than zero.
171 <STRONG>o</STRONG> for each, <STRONG>ncurses</STRONG> updates the corresponding environment variable
172 with the value that it has obtained via operating system call or
173 from the terminal database.
175 <STRONG>o</STRONG> <STRONG>ncurses</STRONG> re-fetches the value of the environment variables so that
176 it is still the environment variables which set the screen size.
178 The <STRONG>use_env</STRONG> and <STRONG>use_tioctl</STRONG> routines combine as summarized here:
180 <STRONG>use_env</STRONG> <STRONG>use_tioctl</STRONG> <STRONG>Summary</STRONG>
181 ----------------------------------------------------------------
185 TRUE FALSE This is the default behavior. <STRONG>ncurses</STRONG>
186 uses operating system calls unless over-
187 ridden by $LINES or $COLUMNS environment
189 TRUE TRUE <STRONG>ncurses</STRONG> updates $LINES and $COLUMNS
190 based on operating system calls.
191 FALSE TRUE <STRONG>ncurses</STRONG> ignores $LINES and $COLUMNS, us-
192 es operating system calls to obtain
194 FALSE FALSE <STRONG>ncurses</STRONG> relies on the terminal database
198 </PRE><H3><a name="h3-putwin_getwin">putwin/getwin</a></H3><PRE>
199 The <STRONG>putwin</STRONG> routine writes all data associated with window (or pad) <EM>win</EM>
200 into the file to which <EM>filep</EM> points. This information can be later re-
201 trieved using the <STRONG>getwin</STRONG> function.
203 The <STRONG>getwin</STRONG> routine reads window related data stored in the file by
204 <STRONG>putwin</STRONG>. The routine then creates and initializes a new window using
205 that data. It returns a pointer to the new window. There are a few
208 <STRONG>o</STRONG> the data written is a copy of the <STRONG>WINDOW</STRONG> structure, and its associ-
209 ated character cells. The format differs between the wide-charac-
210 ter (<STRONG>ncursesw</STRONG>) and non-wide (<STRONG>ncurses</STRONG>) libraries. You can transfer
211 data between the two, however.
213 <STRONG>o</STRONG> the retrieved window is always created as a top-level window (or
214 pad), rather than a subwindow.
216 <STRONG>o</STRONG> the window's character cells contain the color pair <EM>value</EM>, but not
217 the actual color <EM>numbers</EM>. If cells in the retrieved window use
218 color pairs which have not been created in the application using
219 <STRONG>init_pair</STRONG>, they will not be colored when the window is refreshed.
222 </PRE><H3><a name="h3-delay_output">delay_output</a></H3><PRE>
223 The <STRONG>delay_output</STRONG> routine inserts an <EM>ms</EM> millisecond pause in output.
224 This routine should not be used extensively because padding characters
225 are used rather than a CPU pause. If no padding character is speci-
226 fied, this uses <STRONG>napms</STRONG> to perform the delay.
229 </PRE><H3><a name="h3-flushinp">flushinp</a></H3><PRE>
230 The <STRONG>flushinp</STRONG> routine throws away any typeahead that has been typed by
231 the user and has not yet been read by the program.
234 </PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
235 Except for <STRONG>flushinp</STRONG>, routines that return an integer return <STRONG>ERR</STRONG> upon
236 failure and <STRONG>OK</STRONG> (SVr4 specifies only "an integer value other than <STRONG>ERR</STRONG>")
237 upon successful completion.
239 Routines that return pointers return <STRONG>NULL</STRONG> on error.
241 X/Open does not define any error conditions. In this implementation
243 <STRONG>flushinp</STRONG>
244 returns an error if the terminal was not initialized.
246 <STRONG>putwin</STRONG>
247 returns an error if the associated <STRONG>fwrite</STRONG> calls return an er-
251 </PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
253 </PRE><H3><a name="h3-filter">filter</a></H3><PRE>
254 The SVr4 documentation describes the action of <STRONG>filter</STRONG> only in the
255 vaguest terms. The description here is adapted from the XSI Curses
256 standard (which erroneously fails to describe the disabling of <STRONG>cuu</STRONG>).
259 </PRE><H3><a name="h3-keyname">keyname</a></H3><PRE>
260 The <STRONG>keyname</STRONG> function may return the names of user-defined string capa-
261 bilities which are defined in the terminfo entry via the <STRONG>-x</STRONG> option of
262 <STRONG>tic</STRONG>. This implementation automatically assigns at run-time keycodes to
263 user-defined strings which begin with "k". The keycodes start at
264 KEY_MAX, but are not guaranteed to be the same value for different runs
265 because user-defined codes are merged from all terminal descriptions
266 which have been loaded. The <STRONG><A HREF="curs_extend.3x.html">use_extended_names(3x)</A></STRONG> function controls
267 whether this data is loaded when the terminal description is read by
271 </PRE><H3><a name="h3-nofilter_use_tioctl">nofilter/use_tioctl</a></H3><PRE>
272 The <STRONG>nofilter</STRONG> and <STRONG>use_tioctl</STRONG> routines are specific to <STRONG>ncurses</STRONG>. They
273 were not supported on Version 7, BSD or System V implementations. It
274 is recommended that any code depending on <STRONG>ncurses</STRONG> extensions be condi-
275 tioned using NCURSES_VERSION.
278 </PRE><H3><a name="h3-putwin_getwin-file-format">putwin/getwin file-format</a></H3><PRE>
279 The <STRONG>putwin</STRONG> and <STRONG>getwin</STRONG> functions have several issues with portability:
281 <STRONG>o</STRONG> The files written and read by these functions use an implementa-
282 tion-specific format. Although the format is an obvious target for
283 standardization, it has been overlooked.
285 Interestingly enough, according to the copyright dates in Solaris
286 source, the functions (along with <STRONG>scr_init</STRONG>, etc.) originated with
287 the University of California, Berkeley (in 1982) and were later (in
288 1988) incorporated into SVr4. Oddly, there are no such functions
289 in the 4.3BSD curses sources.
291 <STRONG>o</STRONG> Most implementations simply dump the binary <STRONG>WINDOW</STRONG> structure to the
292 file. These include SVr4 curses, NetBSD and PDCurses, as well as
293 older <STRONG>ncurses</STRONG> versions. This implementation (as well as the X/Open
294 variant of Solaris curses, dated 1995) uses textual dumps.
296 The implementations which use binary dumps use block-I/O (the
297 <STRONG>fwrite</STRONG> and <STRONG>fread</STRONG> functions). Those that use textual dumps use
298 buffered-I/O. A few applications may happen to write extra data in
299 the file using these functions. Doing that can run into problems
300 mixing block- and buffered-I/O. This implementation reduces the
301 problem on writes by flushing the output. However, reading from a
302 file written using mixed schemes may not be successful.
305 </PRE><H3><a name="h3-unctrl_wunctrl">unctrl/wunctrl</a></H3><PRE>
306 The XSI Curses standard, Issue 4 describes these functions. It states
307 that <STRONG>unctrl</STRONG> and <STRONG>wunctrl</STRONG> will return a null pointer if unsuccessful, but
308 does not define any error conditions. This implementation checks for
311 <STRONG>o</STRONG> the parameter is a 7-bit US-ASCII code. This is the case that
312 X/Open Curses documented.
314 <STRONG>o</STRONG> the parameter is in the range 128-159, i.e., a C1 control code. If
315 <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>
316 returns the parameter, i.e., a one-character string with the param-
317 eter as the first character. Otherwise, it returns "~@", "~A",
318 etc., analogous to "^@", "^A", C0 controls.
320 X/Open Curses does not document whether <STRONG>unctrl</STRONG> can be called before
321 initializing curses. This implementation permits that, and returns
322 the "~@", etc., values in that case.
324 <STRONG>o</STRONG> parameter values outside the 0 to 255 range. <STRONG>unctrl</STRONG> returns a null
327 The strings returned by <STRONG>unctrl</STRONG> in this implementation are determined at
328 compile time, showing C1 controls from the upper-128 codes with a "~"
329 prefix rather than "^". Other implementations have different conven-
330 tions. For example, they may show both sets of control characters with
331 "^", and strip the parameter to 7 bits. Or they may ignore C1 controls
332 and treat all of the upper-128 codes as printable. This implementation
333 uses 8 bits but does not modify the string to reflect locale. The
334 <STRONG><A HREF="legacy_coding.3x.html">use_legacy_coding(3x)</A></STRONG> function allows the caller to change the output
335 of <STRONG>unctrl</STRONG>.
337 Likewise, the <STRONG><A HREF="curs_inopts.3x.html">meta(3x)</A></STRONG> function allows the caller to change the output
338 of <STRONG>keyname</STRONG>, i.e., it determines whether to use the "M-" prefix for
339 "meta" keys (codes in the range 128 to 255). Both <STRONG>use_legacy_cod-</STRONG>
340 <STRONG><A HREF="use_legacy_coding.3x.html">ing(3x)</A></STRONG> and <STRONG><A HREF="curs_inopts.3x.html">meta(3x)</A></STRONG> succeed only after curses is initialized. X/Open
341 Curses does not document the treatment of codes 128 to 159. When
342 treating them as "meta" keys (or if <STRONG>keyname</STRONG> is called before initializ-
343 ing curses), this implementation returns strings "M-^@", "M-^A", etc.
345 X/Open Curses documents <STRONG>unctrl</STRONG> as declared in <STRONG><unctrl.h></STRONG>, which <STRONG>ncurses</STRONG>
346 does. However, <STRONG>ncurses</STRONG>' <STRONG><curses.h></STRONG> includes <STRONG><unctrl.h></STRONG>, matching the
347 behavior of SVr4 curses. Other implementations may not do that.
350 </PRE><H3><a name="h3-use_env_use_tioctl">use_env/use_tioctl</a></H3><PRE>
351 If <STRONG>ncurses</STRONG> is configured to provide the sp-functions extension, the
352 state of <STRONG>use_env</STRONG> and <STRONG>use_tioctl</STRONG> may be updated before creating each
353 <EM>screen</EM> rather than once only (<STRONG><A HREF="curs_sp_funcs.3x.html">curs_sp_funcs(3x)</A></STRONG>). This feature of
354 <STRONG>use_env</STRONG> is not provided by other implementation of curses.
357 </PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE>
358 <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>,
359 <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>legacy_cod-</STRONG>
360 <STRONG><A HREF="legacy_coding.3x.html">ing(3x)</A></STRONG>.
364 <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>
368 <li><a href="#h2-NAME">NAME</a></li>
369 <li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li>
370 <li><a href="#h2-DESCRIPTION">DESCRIPTION</a>
372 <li><a href="#h3-unctrl">unctrl</a></li>
373 <li><a href="#h3-keyname_key_name">keyname/key_name</a></li>
374 <li><a href="#h3-filter_nofilter">filter/nofilter</a></li>
375 <li><a href="#h3-use_env">use_env</a></li>
376 <li><a href="#h3-use_tioctl">use_tioctl</a></li>
377 <li><a href="#h3-putwin_getwin">putwin/getwin</a></li>
378 <li><a href="#h3-delay_output">delay_output</a></li>
379 <li><a href="#h3-flushinp">flushinp</a></li>
382 <li><a href="#h2-RETURN-VALUE">RETURN VALUE</a></li>
383 <li><a href="#h2-PORTABILITY">PORTABILITY</a>
385 <li><a href="#h3-filter">filter</a></li>
386 <li><a href="#h3-keyname">keyname</a></li>
387 <li><a href="#h3-nofilter_use_tioctl">nofilter/use_tioctl</a></li>
388 <li><a href="#h3-putwin_getwin-file-format">putwin/getwin file-format</a></li>
389 <li><a href="#h3-unctrl_wunctrl">unctrl/wunctrl</a></li>
390 <li><a href="#h3-use_env_use_tioctl">use_env/use_tioctl</a></li>
393 <li><a href="#h2-SEE-ALSO">SEE ALSO</a></li>