php-doc-en/reference/readline/functions/readline-callback-handler-install.xml
2021-06-10 12:20:48 +03:00

140 lines
3.5 KiB
XML

<?xml version="1.0" encoding="utf-8"?>
<!-- $Revision$ -->
<refentry xml:id="function.readline-callback-handler-install" xmlns="http://docbook.org/ns/docbook">
<refnamediv>
<refname>readline_callback_handler_install</refname>
<refpurpose>Initializes the readline callback interface and terminal, prints the prompt and returns immediately</refpurpose>
</refnamediv>
<refsect1 role="description">
&reftitle.description;
<methodsynopsis>
<type>bool</type><methodname>readline_callback_handler_install</methodname>
<methodparam><type>string</type><parameter>prompt</parameter></methodparam>
<methodparam><type>callable</type><parameter>callback</parameter></methodparam>
</methodsynopsis>
<para>
Sets up a readline callback interface then prints
<parameter>prompt</parameter> and immediately returns.
Calling this function twice without removing the previous
callback interface will automatically and conveniently overwrite the old
interface.
</para>
<para>
The callback feature is useful when combined with
<function>stream_select</function> as it allows interleaving of IO and
user input, unlike <function>readline</function>.
</para>
</refsect1>
<refsect1 role="parameters">
&reftitle.parameters;
<para>
<variablelist>
<varlistentry>
<term><parameter>prompt</parameter></term>
<listitem>
<para>
The prompt message.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>callback</parameter></term>
<listitem>
<para>
The <parameter>callback</parameter> function takes one parameter; the
user input returned.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect1>
<refsect1 role="returnvalues">
&reftitle.returnvalues;
<para>
&return.success;
</para>
</refsect1>
<refsect1 role="examples">
&reftitle.examples;
<para>
<example>
<title>Readline Callback Interface Example</title>
<programlisting role="php">
<![CDATA[
<?php
function rl_callback($ret)
{
global $c, $prompting;
echo "You entered: $ret\n";
$c++;
if ($c > 10) {
$prompting = false;
readline_callback_handler_remove();
} else {
readline_callback_handler_install("[$c] Enter something: ", 'rl_callback');
}
}
$c = 1;
$prompting = true;
readline_callback_handler_install("[$c] Enter something: ", 'rl_callback');
while ($prompting) {
$w = NULL;
$e = NULL;
$n = stream_select($r = array(STDIN), $w, $e, null);
if ($n && in_array(STDIN, $r)) {
// read a character, will call the callback when a newline is entered
readline_callback_read_char();
}
}
echo "Prompting disabled. All done.\n";
?>
]]>
</programlisting>
</example>
</para>
</refsect1>
<refsect1 role="seealso">
&reftitle.seealso;
<para>
<simplelist>
<member><function>readline_callback_handler_remove</function></member>
<member><function>readline_callback_read_char</function></member>
<member><function>stream_select</function></member>
</simplelist>
</para>
</refsect1>
</refentry>
<!-- Keep this comment at the end of the file
Local variables:
mode: sgml
sgml-omittag:t
sgml-shorttag:t
sgml-minimize-attributes:nil
sgml-always-quote-attributes:t
sgml-indent-step:1
sgml-indent-data:t
indent-tabs-mode:nil
sgml-parent-document:nil
sgml-default-dtd-file:"~/.phpdoc/manual.ced"
sgml-exposed-tags:nil
sgml-local-catalogs:nil
sgml-local-ecat-files:nil
End:
vim600: syn=xml fen fdm=syntax fdl=2 si
vim: et tw=78 syn=sgml
vi: ts=1 sw=1
-->