<?xml version="1.0" encoding="utf-8"?>

<sect1 xml:id="language.operators.execution">

<title>Execution Operators</title>

<titleabbrev>Execution</titleabbrev>

<para>

PHP supports one execution operator: backticks (<literal>``</literal>). Note that

these are not single-quotes! PHP will attempt to execute the

contents of the backticks as a shell command; the output will be

returned (i.e., it won't simply be dumped to output; it can be

assigned to a variable). Use of the backtick operator is identical

to <function>shell_exec</function>.

</para>

<para>

<example>

<title>Backtick Operator</title>

<programlisting role="php" annotations="non-interactive">

</programlisting>

</example>

</para>

<note>

<para>

The backtick operator is disabled when

<function>shell_exec</function> is disabled.

</para>

</note>

<note>

<para>

Unlike some other languages, backticks have no special meaning

within double-quoted strings.

</para>

</note>

<sect2 role="changelog">

&reftitle.changelog;

<informaltable>

<tgroup cols="2">

<thead>

<row>

<entry>&Version;</entry>

<entry>&Description;</entry>

</row>

</thead>

<tbody>

<row>

<entry>8.5.0</entry>

<entry>

The backtick operator as an alias for <function>shell_exec</function> has been deprecated.

</entry>

</row>

</tbody>

</tgroup>

</informaltable>

</sect2>

<sect2 role="seealso">

&reftitle.seealso;

<para>

<simplelist>

<member><link linkend="ref.exec">Program Execution functions</link></member>

<member><function>popen</function></member>

<member><function>proc_open</function></member>

<member><link linkend="features.commandline">Using PHP from the commandline</link></member>

</simplelist>

</para>

</sect2>

</sect1>