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<?xml version="1.0" encoding="iso-8859-1"?>
<!-- $Revision: 1.26 $ -->
<refentry xmlns="http://docbook.org/ns/docbook" xml:id="function.fread">
<refnamediv>
<refname>fread</refname>
<refpurpose>Binary-safe file read</refpurpose>
</refnamediv>
<refsect1 role="description">
&reftitle.description;
<methodsynopsis>
<type>string</type><methodname>fread</methodname>
<methodparam><type>resource</type><parameter>handle</parameter></methodparam>
<methodparam><type>int</type><parameter>length</parameter></methodparam>
</methodsynopsis>
<para>
<function>fread</function> reads up to
<parameter>length</parameter> bytes from the file pointer
referenced by <parameter>handle</parameter>. Reading stops as soon as one
of the following conditions is met:
<itemizedlist>
<listitem>
<simpara>
<parameter>length</parameter> bytes have been read
</simpara>
</listitem>
<listitem>
<simpara>
EOF (end of file) is reached
</simpara>
</listitem>
<listitem>
<simpara>
a packet becomes available (for network streams)
</simpara>
</listitem>
<listitem>
<simpara>
8192 bytes have been read (after opening userspace stream)
</simpara>
</listitem>
</itemizedlist>
</para>
</refsect1>
<refsect1 role="parameters">
&reftitle.parameters;
<para>
<variablelist>
<varlistentry>
<term><parameter>handle</parameter></term>
<listitem>
&fs.file.pointer;
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>length</parameter></term>
<listitem>
<para>
Up to <parameter>length</parameter> number of bytes read.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect1>
<refsect1 role="returnvalues">
&reftitle.returnvalues;
<para>
Returns the read string or &false; in case of error.
</para>
</refsect1>
<refsect1 role="examples">
&reftitle.examples;
<para>
<example>
<title>A simple <function>fread</function> example</title>
<programlisting role="php">
<![CDATA[
<?php
// get contents of a file into a string
$filename = "/usr/local/something.txt";
$handle = fopen($filename, "r");
$contents = fread($handle, filesize($filename));
fclose($handle);
?>
]]>
</programlisting>
</example>
</para>
<para>
<example>
<title>Binary <function>fread</function> example</title>
<warning>
<para>
On systems which differentiate between binary and text files
(i.e. Windows) the file must be opened with 'b' included in
<function>fopen</function> mode parameter.
</para>
</warning>
<programlisting role="php">
<![CDATA[
<?php
$filename = "c:\\files\\somepic.gif";
$handle = fopen($filename, "rb");
$contents = fread($handle, filesize($filename));
fclose($handle);
?>
]]>
</programlisting>
</example>
</para>
<para>
<example>
<title>Remote <function>fread</function> examples</title>
<warning>
<para>
When reading from anything that is not a regular local file, such as
streams returned when
reading <link linkend="features.remote-files">remote files</link> or from
<function>popen</function> and <function>fsockopen</function>, reading
will stop after a packet is available. This means that you should
collect the data together in chunks as shown in the examples below.
</para>
</warning>
<programlisting role="php">
<![CDATA[
<?php
// For PHP 5 and up
$handle = fopen("http://www.example.com/", "rb");
$contents = stream_get_contents($handle);
fclose($handle);
?>
]]>
</programlisting>
<programlisting role="php">
<![CDATA[
<?php
$handle = fopen("http://www.example.com/", "rb");
$contents = '';
while (!feof($handle)) {
$contents .= fread($handle, 8192);
}
fclose($handle);
?>
]]>
</programlisting>
</example>
</para>
</refsect1>
<refsect1 role="notes">
&reftitle.notes;
<note>
<para>
If you just want to get the contents of a file into a string, use
<function>file_get_contents</function> as it has much better performance
than the code above.
</para>
</note>
<note>
<para>
Note that <function>fread</function> reads from the current position of
the file pointer. Use <function>ftell</function> to find the current
position of the pointer and <function>rewind</function> to rewind the
pointer position.
</para>
</note>
</refsect1>
<refsect1 role="seealso">
&reftitle.seealso;
<para>
<simplelist>
<member><function>fwrite</function></member>
<member><function>fopen</function></member>
<member><function>fsockopen</function></member>
<member><function>popen</function></member>
<member><function>fgets</function></member>
<member><function>fgetss</function></member>
<member><function>fscanf</function></member>
<member><function>file</function></member>
<member><function>fpassthru</function></member>
<member><function>ftell</function></member>
<member><function>rewind</function></member>
</simplelist>
</para>
</refsect1>
</refentry>
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