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</PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
<STRONG>#include</STRONG> <STRONG><curses.h></STRONG>
- <STRONG>char</STRONG> <STRONG>*unctrl(chtype</STRONG> <STRONG>c);</STRONG>
+ <STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*unctrl(chtype</STRONG> <STRONG>c);</STRONG>
<STRONG>wchar_t</STRONG> <STRONG>*wunctrl(cchar_t</STRONG> <STRONG>*c);</STRONG>
- <STRONG>char</STRONG> <STRONG>*keyname(int</STRONG> <STRONG>c);</STRONG>
- <STRONG>char</STRONG> <STRONG>*key_name(wchar_t</STRONG> <STRONG>w);</STRONG>
+ <STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*keyname(int</STRONG> <STRONG>c);</STRONG>
+ <STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*key_name(wchar_t</STRONG> <STRONG>w);</STRONG>
<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>
</PRE><H3><a name="h3-filter_nofilter">filter/nofilter</a></H3><PRE>
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> string is set to the value of <STRONG>cr</STRONG>.
+ are called. Calling <STRONG>filter</STRONG> causes these changes in initialization:
- 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>$TERM</STRONG>. The limitation arises because the
+ <STRONG>o</STRONG> <STRONG>LINES</STRONG> is set to 1;
+
+ <STRONG>o</STRONG> the capabilities <STRONG>clear</STRONG>, <STRONG>cud1</STRONG>, <STRONG>cud</STRONG>, <STRONG>cup</STRONG>, <STRONG>cuu1</STRONG>, <STRONG>cuu</STRONG>, <STRONG>vpa</STRONG> are dis-
+ abled;
+
+ <STRONG>o</STRONG> the capability <STRONG>ed</STRONG> is disabled if <STRONG>bce</STRONG> is set;
+
+ <STRONG>o</STRONG> and the <STRONG>home</STRONG> string is set to the value of <STRONG>cr</STRONG>.
+
+ The <STRONG>nofilter</STRONG> routine cancels the effect of a preceding <STRONG>filter</STRONG> call.
+ That allows the caller to initialize a screen on a different device,
+ using a different value of <STRONG>$TERM</STRONG>. The limitation arises because the
<STRONG>filter</STRONG> routine modifies the in-memory copy of the terminal information.
</PRE><H3><a name="h3-use_env">use_env</a></H3><PRE>
- 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 modi-
- fies the way <STRONG>ncurses</STRONG> treats environment variables when determining the
+ 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 modi-
+ fies the way <STRONG>ncurses</STRONG> treats environment variables when determining the
screen size.
- <STRONG>o</STRONG> Normally <STRONG>ncurses</STRONG> looks first at the terminal database for the
+ <STRONG>o</STRONG> Normally <STRONG>ncurses</STRONG> 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 un-
- less If <STRONG>use_tioctl</STRONG> was also called with <STRONG>TRUE</STRONG> for parameter.
+ If <STRONG>use_env</STRONG> was called with <STRONG>FALSE</STRONG> for parameter, it stops here un-
+ less <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
+ <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> parameter), <STRONG>ncurses</STRONG>
- examines the <STRONG>LINES</STRONG> or <STRONG>COLUMNS</STRONG> environment variables, using a value
- in those to override the results from the operating system or ter-
+ <STRONG>o</STRONG> Finally (unless <STRONG>use_env</STRONG> was called with <STRONG>FALSE</STRONG> parameter), <STRONG>ncurses</STRONG>
+ examines the <STRONG>LINES</STRONG> or <STRONG>COLUMNS</STRONG> environment variables, using a value
+ in those to override the results from the operating system or ter-
minal database.
- <STRONG>Ncurses</STRONG> also updates the screen size in response to SIGWINCH, un-
+ <STRONG>Ncurses</STRONG> also updates the screen size in response to <STRONG>SIGWINCH</STRONG>, un-
less overridden by the <STRONG>LINES</STRONG> or <STRONG>COLUMNS</STRONG> environment variables,
</PRE><H3><a name="h3-use_tioctl">use_tioctl</a></H3><PRE>
- 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, <STRONG>ncurses</STRONG> modifies the
+ 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, <STRONG>ncurses</STRONG> modifies the
last step in its computation of screen size as follows:
- <STRONG>o</STRONG> checks if the <STRONG>LINES</STRONG> and <STRONG>COLUMNS</STRONG> environment variables are set to a
+ <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, <STRONG>ncurses</STRONG> updates the corresponding environment variable
- with the value that it has obtained via operating system call or
+ <STRONG>o</STRONG> for each, <STRONG>ncurses</STRONG> updates the corresponding environment variable
+ with the value that it has obtained via operating system call or
from the terminal database.
- <STRONG>o</STRONG> <STRONG>ncurses</STRONG> re-fetches the value of the environment variables so that
+ <STRONG>o</STRONG> <STRONG>ncurses</STRONG> re-fetches the value of the environment variables 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. <STRONG>ncurses</STRONG>
+ TRUE FALSE This is the default behavior. <STRONG>ncurses</STRONG>
uses operating system calls unless over-
ridden by $LINES or $COLUMNS environment
variables.
- TRUE TRUE <STRONG>ncurses</STRONG> updates $LINES and $COLUMNS
+ TRUE TRUE <STRONG>ncurses</STRONG> updates $LINES and $COLUMNS
based on operating system calls.
FALSE TRUE <STRONG>ncurses</STRONG> ignores $LINES and $COLUMNS, us-
es operating system calls to obtain
size.
- FALSE FALSE <STRONG>ncurses</STRONG> relies on the terminal database
+ FALSE FALSE <STRONG>ncurses</STRONG> relies on the terminal database
to determine size.
</PRE><H3><a name="h3-putwin_getwin">putwin/getwin</a></H3><PRE>
- The <STRONG>putwin</STRONG> routine writes all data associated with window (or pad) <EM>win</EM>
+ The <STRONG>putwin</STRONG> routine writes all data associated with window (or pad) <EM>win</EM>
into the file to which <EM>filep</EM> points. This information can be later re-
trieved 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 a new window using
- that data. It returns a pointer to the new window. There are a few
+ The <STRONG>getwin</STRONG> routine reads window related data stored in the 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. There are a few
caveats:
<STRONG>o</STRONG> the data written is a copy of the <STRONG>WINDOW</STRONG> structure, and its associ-
- ated character cells. The format differs between the wide-charac-
- ter (ncursesw) and non-wide (ncurses) libraries. You can transfer
+ ated character cells. The format differs between the wide-charac-
+ ter (<STRONG>ncursesw</STRONG>) and non-wide (<STRONG>ncurses</STRONG>) libraries. You can transfer
data between the two, however.
- <STRONG>o</STRONG> the retrieved window is always created as a top-level window (or
+ <STRONG>o</STRONG> the retrieved window is always created as a top-level window (or
pad), rather than a subwindow.
- <STRONG>o</STRONG> the window's character cells contain the color pair <EM>value</EM>, but not
- the actual color <EM>numbers</EM>. If cells in the retrieved window use
- color pairs which have not been created in the application using
+ <STRONG>o</STRONG> the window's character cells contain the color pair <EM>value</EM>, but not
+ the actual color <EM>numbers</EM>. If cells in the retrieved window use
+ color pairs which have not been created in the application using
<STRONG>init_pair</STRONG>, they will not be colored when the window is refreshed.
</PRE><H3><a name="h3-delay_output">delay_output</a></H3><PRE>
- 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 speci-
+ 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 speci-
fied, this uses <STRONG>napms</STRONG> to perform the delay.
</PRE><H3><a name="h3-flushinp">flushinp</a></H3><PRE>
- The <STRONG>flushinp</STRONG> routine throws away any typeahead that has been typed by
+ 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><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
- Except for <STRONG>flushinp</STRONG>, routines that return an integer return <STRONG>ERR</STRONG> upon
- failure and <STRONG>OK</STRONG> (SVr4 specifies only "an integer value other than <STRONG>ERR</STRONG>")
+ Except for <STRONG>flushinp</STRONG>, routines that return an integer return <STRONG>ERR</STRONG> upon
+ failure and <STRONG>OK</STRONG> (SVr4 specifies only "an integer value other than <STRONG>ERR</STRONG>")
upon successful completion.
Routines that return pointers return <STRONG>NULL</STRONG> on error.
returns an error if the terminal was not initialized.
<STRONG>putwin</STRONG>
- returns an error if the associated <STRONG>fwrite</STRONG> calls return an er-
+ returns an error if the associated <STRONG>fwrite</STRONG> calls return an er-
ror.
</PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
</PRE><H3><a name="h3-filter">filter</a></H3><PRE>
- The SVr4 documentation describes the action of <STRONG>filter</STRONG> only in the
- vaguest terms. The description here is adapted from the XSI Curses
+ The SVr4 documentation describes the action of <STRONG>filter</STRONG> only in the
+ vaguest terms. The description here is adapted from the XSI Curses
standard (which erroneously fails to describe the disabling of <STRONG>cuu</STRONG>).
</PRE><H3><a name="h3-keyname">keyname</a></H3><PRE>
- The <STRONG>keyname</STRONG> function may return the names of user-defined string capa-
- bilities which are defined in the terminfo entry via the <STRONG>-x</STRONG> option of
+ The <STRONG>keyname</STRONG> function may return the names of user-defined string capa-
+ bilities which are defined in the terminfo entry via the <STRONG>-x</STRONG> option of
<STRONG>tic</STRONG>. This implementation automatically assigns at run-time keycodes to
- user-defined strings which begin with "k". The keycodes start at
+ user-defined strings which begin with "k". The keycodes start at
KEY_MAX, but are not guaranteed to be the same value for different runs
- because user-defined codes are merged from all terminal descriptions
- which have been loaded. The <STRONG><A HREF="curs_extend.3x.html">use_extended_names(3x)</A></STRONG> function controls
- whether this data is loaded when the terminal description is read by
+ because user-defined codes are merged from all terminal descriptions
+ which have been loaded. The <STRONG><A HREF="curs_extend.3x.html">use_extended_names(3x)</A></STRONG> function controls
+ whether this data is loaded when the terminal description is read by
the library.
</PRE><H3><a name="h3-nofilter_use_tioctl">nofilter/use_tioctl</a></H3><PRE>
- The <STRONG>nofilter</STRONG> and <STRONG>use_tioctl</STRONG> routines are specific to <STRONG>ncurses</STRONG>. They
- were not supported on Version 7, BSD or System V implementations. It
- is recommended that any code depending on <STRONG>ncurses</STRONG> extensions be condi-
+ The <STRONG>nofilter</STRONG> and <STRONG>use_tioctl</STRONG> routines are specific to <STRONG>ncurses</STRONG>. They
+ were not supported on Version 7, BSD or System V implementations. It
+ is recommended that any code depending on <STRONG>ncurses</STRONG> extensions be condi-
tioned using NCURSES_VERSION.
</PRE><H3><a name="h3-putwin_getwin">putwin/getwin</a></H3><PRE>
The <STRONG>putwin</STRONG> and <STRONG>getwin</STRONG> functions have several issues with portability:
- <STRONG>o</STRONG> The files written and read by these functions use an implementa-
+ <STRONG>o</STRONG> The files written and read by these functions use an implementa-
tion-specific format. Although the format is an obvious target for
standardization, it has been overlooked.
- Interestingly enough, according to the copyright dates in Solaris
- source, the functions (along with <STRONG>scr_init</STRONG>, etc.) originated with
+ Interestingly enough, according to the copyright dates in Solaris
+ source, the functions (along with <STRONG>scr_init</STRONG>, etc.) originated with
the University of California, Berkeley (in 1982) and were later (in
- 1988) incorporated into SVr4. Oddly, there are no such functions
+ 1988) incorporated into SVr4. Oddly, there are no such functions
in the 4.3BSD curses sources.
<STRONG>o</STRONG> Most implementations simply dump the binary <STRONG>WINDOW</STRONG> structure to the
- file. These include SVr4 curses, NetBSD and PDCurses, as well as
+ file. These include SVr4 curses, NetBSD and PDCurses, as well as
older <STRONG>ncurses</STRONG> versions. This implementation (as well as the X/Open
variant of Solaris curses, dated 1995) uses textual dumps.
- The implementations which use binary dumps use block-I/O (the
- <STRONG>fwrite</STRONG> and <STRONG>fread</STRONG> functions). Those that use textual dumps use
+ The implementations which use binary dumps use block-I/O (the
+ <STRONG>fwrite</STRONG> and <STRONG>fread</STRONG> functions). Those that use textual dumps use
buffered-I/O. A few applications may happen to write extra data in
- the file using these functions. Doing that can run into problems
- mixing block- and buffered-I/O. This implementation reduces the
- problem on writes by flushing the output. However, reading from a
+ the file using these functions. Doing that can run into problems
+ mixing block- and buffered-I/O. This implementation reduces the
+ problem on writes by flushing the output. However, reading from a
file written using mixed schemes may not be successful.
</PRE><H3><a name="h3-unctrl_wunctrl">unctrl/wunctrl</a></H3><PRE>
- The XSI Curses standard, Issue 4 describes these functions. It states
+ The XSI Curses standard, Issue 4 describes these functions. It states
that <STRONG>unctrl</STRONG> and <STRONG>wunctrl</STRONG> will return a null pointer if unsuccessful, but
- does not define any error conditions. This implementation checks for
+ does not define any error conditions. This implementation checks for
three cases:
- <STRONG>o</STRONG> the parameter is a 7-bit US-ASCII code. This is the case that
+ <STRONG>o</STRONG> the parameter is a 7-bit US-ASCII code. This is the case that
X/Open Curses documented.
<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> re-
- turns the parameter, i.e., a one-character string with the parame-
- ter as the first character. Otherwise, it returns "~@", "~A",
+ <STRONG>use_legacy_coding</STRONG> has been called with a <STRONG>2</STRONG> parameter, <STRONG>unctrl</STRONG> re-
+ turns the parameter, i.e., a one-character string with the parame-
+ ter 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
pointer.
The strings returned by <STRONG>unctrl</STRONG> in this implementation are determined at
- compile time, showing C1 controls from the upper-128 codes with a "~"
- prefix rather than "^". Other implementations have different conven-
+ compile time, showing C1 controls from the upper-128 codes with a "~"
+ prefix rather than "^". Other implementations have different conven-
tions. For example, they may show both sets of control characters with
"^", and strip the parameter to 7 bits. Or they may ignore C1 controls
and treat all of the upper-128 codes as printable. This implementation
- uses 8 bits but does not modify the string to reflect locale. The
- <STRONG>use_legacy_coding</STRONG> function allows the caller to change the output of
+ uses 8 bits but does not modify the string to reflect locale. The
+ <STRONG>use_legacy_coding</STRONG> function allows the caller to change the output of
<STRONG>unctrl</STRONG>.
- Likewise, the <STRONG><A HREF="curs_inopts.3x.html">meta(3x)</A></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 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
+ Likewise, the <STRONG><A HREF="curs_inopts.3x.html">meta(3x)</A></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 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.
+ X/Open Curses documents <STRONG>unctrl</STRONG> as declared in <STRONG><unctrl.h></STRONG>, which <STRONG>ncurses</STRONG>
+ does. However, <STRONG>ncurses</STRONG>' <STRONG><curses.h></STRONG> includes <STRONG><unctrl.h></STRONG>, matching the
+ behavior of SVr4 curses. Other implementations may not do that.
+
</PRE><H3><a name="h3-use_env_use_tioctl">use_env/use_tioctl</a></H3><PRE>
- If <STRONG>ncurses</STRONG> is configured to provide the sp-functions extension, the
- state of <STRONG>use_env</STRONG> and <STRONG>use_tioctl</STRONG> may be updated before creating each
- <EM>screen</EM> rather than once only (<STRONG><A HREF="curs_sp_funcs.3x.html">curs_sp_funcs(3x)</A></STRONG>). This feature of
+ If <STRONG>ncurses</STRONG> is configured to provide the sp-functions extension, the
+ state of <STRONG>use_env</STRONG> and <STRONG>use_tioctl</STRONG> may be updated before creating each
+ <EM>screen</EM> rather than once only (<STRONG><A HREF="curs_sp_funcs.3x.html">curs_sp_funcs(3x)</A></STRONG>). This feature of
<STRONG>use_env</STRONG> is not provided by other implementation of curses.
projects / ncurses.git / blobdiff