Remove migration guides for PHP 5

Co-authored-by: Christoph M. Becker <cmbecker69@gmx.de>

Closes GH-157.
This commit is contained in:
George Peter Banyard 2020-10-18 18:29:36 +01:00 committed by Christoph M. Becker
parent a2afb71b63
commit 027f187b3e
15 changed files with 4 additions and 9824 deletions

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@ -6,9 +6,8 @@
<sect1 xml:id="debugger-about">
<title>About debugging in PHP</title>
<simpara>
PHP 5.6 is shipped with the <link linkend="migration56.new-features.phpdbg">phpdbg interactive debugger</link>.
PHP versions below 5.6 do not have an internal debugging facility though.
You can use one of the external debuggers though. The
PHP is shipped with the <link linkend="migration56.new-features.phpdbg">phpdbg</link> interactive debugger.
External debuggers can also be used. The
<link xlink:href="&url.zend.ide;">Zend IDE</link> includes
a debugger, and there are also some free debugger extensions
like DBG at <link xlink:href="&url.dbg;">&url.dbg;</link>, the

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@ -135,12 +135,6 @@
<entry>PHP_INI_ALL with restrictions</entry>
<entry>Available since PHP 7.0.0.</entry>
</row>
<row>
<entry><link linkend="ini.zend.ze1-compatibility-mode">zend.ze1_compatibility_mode</link></entry>
<entry>"0"</entry>
<entry>PHP_INI_ALL</entry>
<entry>Removed in PHP 5.3.0</entry>
</row>
<row>
<entry>detect_unicode</entry>
<entry>"1"</entry>
@ -416,32 +410,7 @@
</note>
</listitem>
</varlistentry>
<varlistentry xml:id="ini.zend.ze1-compatibility-mode">
<term>
<parameter>zend.ze1_compatibility_mode</parameter>
<type>bool</type>
</term>
<listitem>
<para>
Enable compatibility mode with Zend Engine 1 (PHP 4). It affects
the cloning, casting (objects with no properties cast to &false; or 0), and <link
linkend="language.oop5.object-comparison">comparing of objects</link>.
In this mode, objects are passed by value instead of reference by
default.
</para>
<para>
See also the section titled
<link linkend="migration5">Migrating from PHP 4 to PHP 5</link>.
</para>
<warning>
<simpara>This feature has been <emphasis>DEPRECATED</emphasis> and <emphasis>REMOVED</emphasis>
as of PHP 5.3.0.
</simpara>
</warning>
</listitem>
</varlistentry>
<varlistentry xml:id="ini.hard-timeout">
<term>
<parameter>hard_timeout</parameter>

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@ -2530,12 +2530,6 @@
<entry>PHP_INI_SYSTEM</entry>
<entry>Available since PHP 5.4.0</entry>
</row>
<row>
<entry><link linkend="ini.zend.ze1-compatibility-mode">zend.ze1_compatibility_mode</link></entry>
<entry>"0"</entry>
<entry>PHP_INI_ALL</entry>
<entry>Available since PHP 5.0.0. Removed in PHP 5.3.0.</entry>
</row>
<row>
<entry><link linkend="ini.zend-extension">zend_extension</link></entry>
<entry>NULL</entry>

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@ -1,977 +0,0 @@
<?xml version="1.0" encoding="utf-8"?>
<!-- $Revision$ -->
<appendix xml:id="migration5" xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink">
<title>Migrating from PHP 4 to PHP 5.0.x</title>
<para>
&manual.migration.seealso;
<link linkend="migration51">5.1.x</link>,
<link linkend="migration52">5.2.x</link>,
<link linkend="migration53">5.3.x</link>,
<link linkend="migration54">5.4.x</link>,
<link linkend="migration55">5.5.x</link> and
<link linkend="migration56">5.6.x</link>.
</para>
<section xml:id="migration5.changes">
<title>What has changed in PHP 5.0.x</title>
<para>
PHP 5 and the integrated Zend Engine 2 have greatly improved PHP's
performance and capabilities, but great care has been taken to break as
little existing code as possible. So migrating your code from PHP 4 to 5
should be very easy. Most existing PHP 4 code should be ready to run
without changes, but you should still know about the <link
linkend="migration5.incompatible">few differences</link> and
take care to test your code before switching versions in production
environments.
</para>
</section>
<section xml:id="migration5.incompatible">
<title>Backward Incompatible Changes</title>
<para>
Although most existing PHP 4 code should work without changes, you should
pay attention to the following backward incompatible changes:
</para>
<itemizedlist>
<listitem>
<simpara>
There are some <link linkend="reserved.keywords">new reserved
keywords</link>.
</simpara>
</listitem>
<listitem>
<simpara>
<function>strrpos</function> and <function>strripos</function> now use
the entire string as a needle.
</simpara>
</listitem>
<listitem>
<simpara>
Illegal use of string offsets causes <constant>E_ERROR</constant> instead
of <constant>E_WARNING</constant>. An example illegal use is:
<literal>$str = 'abc'; unset($str[0]);</literal>.
</simpara>
</listitem>
<listitem>
<simpara>
<function>array_merge</function> was changed to accept only arrays. If a
non-array variable is passed, a <constant>E_WARNING</constant> will be
thrown for every such parameter. Be careful because your code may start
emitting <constant>E_WARNING</constant> out of the blue.
</simpara>
</listitem>
<listitem>
<simpara>
<constant>PATH_TRANSLATED</constant> server variable is no longer set implicitly under
Apache2 SAPI in contrast to the situation in PHP 4, where it is set to
the same value as the <constant>SCRIPT_FILENAME</constant> server variable when it is not
populated by Apache. This change was made to comply with the <link
xlink:href="&url.rfc;3875">CGI/1.1 specification</link>. Please refer to <link
xlink:href="&url.php.bugs;23610">bug #23610</link> for further information,
and see also the <varname>$_SERVER['PATH_TRANSLATED']</varname>
description in the manual. This issue
also affects PHP versions &gt;= 4.3.2.
</simpara>
</listitem>
<listitem>
<simpara>
The <constant>T_ML_COMMENT</constant> constant is no longer defined by
the <link linkend="ref.tokenizer">Tokenizer</link> extension. If
error_reporting is set to <constant>E_ALL</constant>, PHP will
generate a notice. Although the <constant>T_ML_COMMENT</constant> was
never used at all, it was defined in PHP 4. In both PHP 4 and PHP 5
// and /* */ are resolved as the <constant>T_COMMENT</constant>
constant. However the PHPDoc style comments <literal>/** */</literal>, which starting PHP
5 are parsed by PHP, are recognized as <constant>T_DOC_COMMENT</constant>.
</simpara>
</listitem>
<listitem>
<simpara>
<varname>$_SERVER</varname> should be populated with <varname>argc</varname> and
<varname>argv</varname> if
<link linkend="ini.variables-order">variables_order</link> includes "S".
If you have specifically configured your system to not create
<varname>$_SERVER</varname>, then of course it shouldn't be there.
The change was to always make <varname>argc</varname>
and <varname>argv</varname> available in the CLI version regardless of the
<link linkend="ini.variables-order">variables_order</link> setting.
As in, the CLI version will now always populate the global
<varname>$argc</varname> and <varname>$argv</varname> variables.
</simpara>
</listitem>
<listitem>
<simpara>
An object with no properties is no longer considered "empty".
</simpara>
</listitem>
<listitem>
<simpara>
In some cases classes must be declared before use. It only happens if
some of the new features of PHP 5 (such as <link
linkend="language.oop5.interfaces">interfaces</link>) are used.
Otherwise the behaviour is the old.
</simpara>
</listitem>
<listitem>
<simpara>
<function>get_class</function>, <function>get_parent_class</function>
and <function>get_class_methods</function> now return the name of the
classes/methods as they were declared (case-sensitive) which may lead to
problems in older scripts that rely on the previous behaviour (the
class/method name was always returned lowercased). A possible solution
is to search for those functions in all your scripts and use
<function>strtolower</function>.
</simpara>
<simpara>
This case sensitivity change also applies to the
<link linkend="language.constants.predefined">magical predefined
constants</link> <constant>__CLASS__</constant>,
<constant>__METHOD__</constant>, and <constant>__FUNCTION__</constant>.
The values are returned exactly as they're declared (case-sensitive).
</simpara>
</listitem>
<listitem>
<simpara>
<function>ip2long</function> now returns &false; when an invalid IP
address is passed as argument to the function, and no longer
<literal>-1</literal>.
</simpara>
</listitem>
<listitem>
<simpara>
If there are functions defined in the included file, they can be used in the
main file independent if they are before <function>return</function> or after.
If the file is included twice, PHP 5 issues fatal error because functions
were already declared, while PHP 4 doesn't complain about it.
It is recommended to use <function>include_once</function> instead of
checking if the file was already included and conditionally return inside
the included file.
</simpara>
</listitem>
<listitem>
<simpara>
<function>include_once</function> and <function>require_once</function>
first normalize the path of included file on Windows so that including
A.php and a.php include the file just once.
</simpara>
</listitem>
<listitem>
<simpara>
Passing an array to a function by value no longer resets the
array's internal pointer for array accesses made within the
function. In other words, in PHP 4 when you passed an array to a
function, its internal pointer inside the function would be
reset, while in PHP 5, when you pass an array to a function, its
array pointer within the function will be wherever it was when
the array was passed to the function.
</simpara>
</listitem>
</itemizedlist>
<para>
<example>
<title><function>strrpos</function> and <function>strripos</function> now
use the entire string as a needle</title>
<programlisting role="php">
<![CDATA[
<?php
var_dump(strrpos('ABCDEF','DEF')); //int(3)
var_dump(strrpos('ABCDEF','DAF')); //bool(false)
?>
]]>
</programlisting>
</example>
</para>
<para>
<example>
<title>An object with no properties is no longer considered "empty"</title>
<programlisting role="php">
<![CDATA[
<?php
class test { }
$t = new test();
var_dump(empty($t)); // echo bool(false)
if ($t) {
// Will be executed
}
?>
]]>
</programlisting>
</example>
</para>
<para>
<example>
<title>In some cases classes must be declared before used</title>
<programlisting role="php">
<![CDATA[
<?php
//works with no errors:
$a = new a();
class a {
}
//throws an error:
$a = new b();
interface c{
}
class b implements c {
}
?>
]]>
</programlisting>
</example>
</para>
</section>
<section xml:id="migration5.cli-cgi">
<title>CLI and CGI</title>
<para>
In PHP 5 there were some changes in CLI and CGI filenames. In PHP 5, the
CGI version was renamed to <filename>php-cgi.exe</filename> (previously
<filename>php.exe</filename>) and the CLI version now sits in the main
directory (previously <filename>cli/php.exe</filename>).
</para>
<para>
In PHP 5 it was also introduced a new mode:
<filename>php-win.exe</filename>. This is equal to the CLI version, except
that php-win doesn't output anything and thus provides no console (no "dos
box" appears on the screen). This behavior is similar to php-gtk.
</para>
<para>
In PHP 5, the CLI version will always populate the global
<varname>$argv</varname> and <varname>$argc</varname> variables regardless
of any &php.ini; directive setting. Even having
<link linkend="ini.register-argc-argv">register_argc_argv</link> set to
<literal>off</literal> will have no affect in CLI.
</para>
<para>
See also the <link linkend="features.commandline">command line
reference</link>.
</para>
</section>
<section xml:id="migration5.configuration">
<title>Migrating Configuration Files</title>
<para>
Since the ISAPI modules changed their names, from php4xxx to php5xxx, you
need to make some changes in the configuration files. There were also
changes in the CLI and CGI filenames. Please refer to the <link
linkend="migration5.cli-cgi">corresponding section</link> for more
information.
</para>
<para>
Migrating the Apache configuration is extremely easy. See the example below
to check the change you need to do:
<example>
<title>Migrating Apache configuration files for PHP 5</title>
<programlisting role="apache-conf">
<![CDATA[
# change this line:
LoadModule php4_module /php/sapi/php4apache2.dll
# with this one:
LoadModule php5_module /php/php5apache2.dll
]]>
</programlisting>
</example>
</para>
<para>
If your web server is running PHP in CGI mode, you should note that the
CGI version has changed its name from <filename>php.exe</filename> to
<filename>php-cgi.exe</filename>.
In Apache, you should do something like this:
<example>
<title>Migrating Apache configuration files for PHP 5, CGI mode</title>
<programlisting role="apache-conf">
<![CDATA[
# change this line:
Action application/x-httpd-php "/php/php.exe"
# with this one:
Action application/x-httpd-php "/php/php-cgi.exe"
]]>
</programlisting>
</example>
</para>
<para>
In other web servers you need to change either the CGI or the ISAPI module
filenames.
</para>
</section>
<section xml:id="migration5.functions">
<title>New Functions</title>
<para>
In PHP 5 there are some new functions. Here is the list of them:
</para>
<para><link linkend="ref.array">Arrays</link>:</para>
<itemizedlist>
<listitem>
<simpara>
<function>array_combine</function> - Creates an array by using one array
for keys and another for its values
</simpara>
</listitem>
<listitem>
<simpara>
<function>array_diff_uassoc</function> - Computes the difference of
arrays with additional index check which is performed by a user supplied
callback function
</simpara>
</listitem>
<listitem>
<simpara>
<function>array_udiff</function> - Computes the difference of arrays by
using a callback function for data comparison
</simpara>
</listitem>
<listitem>
<simpara>
<function>array_udiff_assoc</function> - Computes the difference of
arrays with additional index check. The data is compared by using a
callback function
</simpara>
</listitem>
<listitem>
<simpara>
<function>array_udiff_uassoc</function> - Computes the difference of
arrays with additional index check. The data is compared by using a
callback function. The index check is done by a callback function also
</simpara>
</listitem>
<listitem>
<simpara>
<function>array_walk_recursive</function> - Apply a user function
recursively to every member of an array
</simpara>
</listitem>
<listitem>
<simpara>
<function>array_uintersect_assoc</function> - Computes the intersection of
arrays with additional index check. The data is compared by using a
callback function
</simpara>
</listitem>
<listitem>
<simpara>
<function>array_uintersect_uassoc</function> - Computes the intersection of
arrays with additional index check. Both the data and the indexes are compared
by using separate callback functions
</simpara>
</listitem>
<listitem>
<simpara>
<function>array_uintersect</function> - Computes the intersection of arrays.
The data is compared by using a callback function
</simpara>
</listitem>
</itemizedlist>
<para><link linkend="ref.ibase">InterBase</link>:</para>
<itemizedlist>
<listitem>
<simpara>
<function>ibase_affected_rows</function> - Return the number of rows
that were affected by the previous query
</simpara>
</listitem>
<listitem>
<simpara>
<function>ibase_backup</function> - Initiates a backup task in the
service manager and returns immediately
</simpara>
</listitem>
<listitem>
<simpara>
<function>ibase_commit_ret</function> - Commit a transaction without
closing it
</simpara>
</listitem>
<listitem>
<simpara>
<function>ibase_db_info</function> - Request statistics about a
database
</simpara>
</listitem>
<listitem>
<simpara>
<function>ibase_drop_db</function> - Drops a database
</simpara>
</listitem>
<listitem>
<simpara>
<function>ibase_errcode</function> - Return an error code
</simpara>
</listitem>
<listitem>
<simpara>
<function>ibase_free_event_handler</function> - Cancels a registered
event handler
</simpara>
</listitem>
<listitem>
<simpara>
<function>ibase_gen_id</function> - Increments the named generator and
returns its new value
</simpara>
</listitem>
<listitem>
<simpara>
<function>ibase_maintain_db</function> - Execute a maintenance command
on the database server
</simpara>
</listitem>
<listitem>
<simpara>
<function>ibase_name_result</function> - Assigns a name to a result set
</simpara>
</listitem>
<listitem>
<simpara>
<function>ibase_num_params</function> - Return the number of parameters
in a prepared query
</simpara>
</listitem>
<listitem>
<simpara>
<function>ibase_param_info</function> - Return information about a
parameter in a prepared query
</simpara>
</listitem>
<listitem>
<simpara>
<function>ibase_restore</function> - Initiates a restore task in the
service manager and returns immediately
</simpara>
</listitem>
<listitem>
<simpara>
<function>ibase_rollback_ret</function> - Rollback transaction and
retain the transaction context
</simpara>
</listitem>
<listitem>
<simpara>
<function>ibase_server_info</function> - Request statistics about a
database server
</simpara>
</listitem>
<listitem>
<simpara>
<function>ibase_service_attach</function> - Connect to the service manager
</simpara>
</listitem>
<listitem>
<simpara>
<function>ibase_service_detach</function> - Disconnect from the
service manager
</simpara>
</listitem>
<listitem>
<simpara>
<function>ibase_set_event_handler</function> - Register a callback
function to be called when events are posted
</simpara>
</listitem>
<listitem>
<simpara>
<function>ibase_wait_event</function> - Wait for an event to be posted
by the database
</simpara>
</listitem>
</itemizedlist>
<para><link linkend="ref.iconv">iconv</link>:</para>
<itemizedlist>
<listitem>
<simpara>
<function>iconv_mime_decode</function> - Decodes a MIME header field
</simpara>
</listitem>
<listitem>
<simpara>
<function>iconv_mime_decode_headers</function> - Decodes multiple MIME
header fields at once
</simpara>
</listitem>
<listitem>
<simpara>
<function>iconv_mime_encode</function> - Composes a MIME header field
</simpara>
</listitem>
<listitem>
<simpara>
<function>iconv_strlen</function> - Returns the character count of
string
</simpara>
</listitem>
<listitem>
<simpara>
<function>iconv_strpos</function> - Finds position of first occurrence
of a needle within a haystack
</simpara>
</listitem>
<listitem>
<simpara>
<function>iconv_strrpos</function> - Finds the last occurrence of a
needle within a haystack
</simpara>
</listitem>
<listitem>
<simpara>
<function>iconv_substr</function> - Cut out part of a string
</simpara>
</listitem>
</itemizedlist>
<para><link linkend="ref.stream">Streams</link>:</para>
<itemizedlist>
<listitem>
<simpara>
<function>stream_copy_to_stream</function> - Copies data from one stream
to another
</simpara>
</listitem>
<listitem>
<simpara>
<function>stream_get_line</function> - Gets line from stream resource up
to a given delimiter
</simpara>
</listitem>
<listitem>
<simpara>
<function>stream_socket_accept</function> - Accept a connection on a
socket created by <function>stream_socket_server</function>
</simpara>
</listitem>
<listitem>
<simpara>
<function>stream_socket_client</function> - Open Internet or Unix domain
socket connection
</simpara>
</listitem>
<listitem>
<simpara>
<function>stream_socket_get_name</function> - Retrieve the name of the
local or remote sockets
</simpara>
</listitem>
<listitem>
<simpara>
<function>stream_socket_recvfrom</function> - Receives data from a
socket, connected or not
</simpara>
</listitem>
<listitem>
<simpara>
<function>stream_socket_sendto</function> - Sends a message to a socket,
whether it is connected or not
</simpara>
</listitem>
<listitem>
<simpara>
<function>stream_socket_server</function> - Create an Internet or Unix
domain server socket
</simpara>
</listitem>
</itemizedlist>
<para><link linkend="ref.datetime">Date and time related</link>:</para>
<itemizedlist>
<listitem>
<simpara>
<function>idate</function> - Format a local time/date as integer
</simpara>
</listitem>
<listitem>
<simpara>
<function>date_sunset</function> - Time of sunset for a given day and
location
</simpara>
</listitem>
<listitem>
<simpara>
<function>date_sunrise</function> - Time of sunrise for a given day and
location
</simpara>
</listitem>
<listitem>
<simpara>
<function>time_nanosleep</function> - Delay for a number of seconds and
nanoseconds
</simpara>
</listitem>
</itemizedlist>
<para><link linkend="ref.strings">Strings</link>:</para>
<itemizedlist>
<listitem>
<simpara>
<function>str_split</function> - Convert a string to an array
</simpara>
</listitem>
<listitem>
<simpara>
<function>strpbrk</function> - Search a string for any of a set of
characters
</simpara>
</listitem>
<listitem>
<simpara>
<function>substr_compare</function> - Binary safe optionally case
insensitive comparison of two strings from an offset, up to length
characters
</simpara>
</listitem>
</itemizedlist>
<para>Other:</para>
<itemizedlist>
<listitem>
<simpara>
<function>convert_uudecode</function> - decode a uuencoded string
</simpara>
</listitem>
<listitem>
<simpara>
<function>convert_uuencode</function> - uuencode a string
</simpara>
</listitem>
<listitem>
<simpara>
<function>curl_copy_handle</function> - Copy a cURL handle
along with all of its preferences
</simpara>
</listitem>
<listitem>
<simpara>
<function>dba_key_split</function> - Splits a key in string
representation into array representation
</simpara>
</listitem>
<listitem>
<simpara>
<function>dbase_get_header_info</function> - Get the header info of a
dBase database
</simpara>
</listitem>
<listitem>
<simpara>
<function>dbx_fetch_row</function> - Fetches rows from a query-result
that had the <constant>DBX_RESULT_UNBUFFERED</constant> flag set
</simpara>
</listitem>
<listitem>
<simpara>
<function>fbsql_set_password</function> - Change the password for a
given user
</simpara>
</listitem>
<listitem>
<simpara>
<function>file_put_contents</function> - Write a string to a file
</simpara>
</listitem>
<listitem>
<simpara>
<function>ftp_alloc</function> - Allocates space for a file to be
uploaded
</simpara>
</listitem>
<listitem>
<simpara>
<function>get_declared_interfaces</function> - Returns an array of all
declared interfaces
</simpara>
</listitem>
<listitem>
<simpara>
<function>get_headers</function> - Fetches all the headers sent by the
server in response to a HTTP request
</simpara>
</listitem>
<listitem>
<simpara>
<function>headers_list</function> - Returns a list of response headers
sent (or ready to send)
</simpara>
</listitem>
<listitem>
<simpara>
<function>http_build_query</function> - Generate URL-encoded query string
</simpara>
</listitem>
<listitem>
<simpara>
<function>image_type_to_extension</function> - Get file extension for
image-type returned by <function>getimagesize</function>,
<function>exif_read_data</function>,
<function>exif_thumbnail</function>,
<function>exif_imagetype</function>
</simpara>
</listitem>
<listitem>
<simpara>
<function>imagefilter</function> - Applies a filter to an image using
custom arguments
</simpara>
</listitem>
<listitem>
<simpara>
<function>imap_getacl</function> - Gets the ACL for a given mailbox
</simpara>
</listitem>
<listitem>
<simpara>
<function>ldap_sasl_bind</function> - Bind to LDAP directory using SASL
</simpara>
</listitem>
<listitem>
<simpara>
<function>mb_list_encodings</function> - Returns an array of all
supported encodings
</simpara>
</listitem>
<listitem>
<simpara>
<function>pcntl_getpriority</function> - Get the priority of any
process
</simpara>
</listitem>
<listitem>
<simpara>
<function>pcntl_wait</function> - Waits on or returns the status of a
forked child as defined by the <literal>waitpid()</literal> system call
</simpara>
</listitem>
<listitem>
<simpara>
<function>pg_version</function> - Returns an array with client, protocol
and server version (when available)
</simpara>
</listitem>
<listitem>
<simpara>
<function>php_check_syntax</function> - Check the syntax of the
specified file
</simpara>
</listitem>
<listitem>
<simpara>
<function>php_strip_whitespace</function> - Return source with stripped
comments and whitespace
</simpara>
</listitem>
<listitem>
<simpara>
<function>proc_nice</function> - Change the priority of the current
process
</simpara>
</listitem>
<listitem>
<simpara>
<function>pspell_config_data_dir</function> - Change location of
language data files
</simpara>
</listitem>
<listitem>
<simpara>
<function>pspell_config_dict_dir</function> - Change location of the
main word list
</simpara>
</listitem>
<listitem>
<simpara>
<function>setrawcookie</function> - Send a cookie without URL-encoding
the value
</simpara>
</listitem>
<listitem>
<simpara>
<function>scandir</function> - List files and directories inside the
specified path
</simpara>
</listitem>
<listitem>
<simpara>
<function>snmp_read_mib</function> - Reads and parses a MIB file into
the active MIB tree
</simpara>
</listitem>
<listitem>
<simpara>
<function>sqlite_fetch_column_types</function> - Return an array of
column types from a particular table
</simpara>
</listitem>
</itemizedlist>
<note>
<para>
The <link linkend="ref.tidy">Tidy</link> extension has also changed its
API completely.
</para>
</note>
</section>
<section xml:id="migration5.newconf">
<title>New Directives</title>
<para>
There were some new &php.ini; directives introduced in PHP 5. Here is a
list of them:
</para>
<itemizedlist>
<listitem>
<simpara>
<link linkend="ini.mail.force_extra_parameters">mail.force_extra_parameters</link> -
Force the addition of the specified
parameters to be passed as extra parameters to the sendmail binary.
These parameters will always replace the value of the 5th parameter to
<function>mail</function>, even in safe mode
</simpara>
</listitem>
<listitem>
<simpara>
<link linkend="ini.register-long-arrays">register_long_arrays</link> -
allow/disallow PHP to register the deprecated long <varname>$HTTP_*_VARS</varname>
</simpara>
</listitem>
<listitem>
<simpara>
<link linkend="ini.session.hash-function">session.hash_function</link> -
select a hash function (MD5 or SHA-1)
</simpara>
</listitem>
<listitem>
<simpara>
<link
linkend="ini.session.hash-bits-per-character">session.hash_bits_per_character</link>
- define how many bits are stored in each character when converting the
binary hash data to something readable (from 4 to 6)
</simpara>
</listitem>
<listitem>
<simpara>
<link linkend="ini.zend.ze1-compatibility-mode">zend.ze1_compatibility_mode</link>
- Enable compatibility mode with Zend Engine 1 (PHP 4)
</simpara>
</listitem>
</itemizedlist>
</section>
<section xml:id="migration5.databases">
<title>Databases</title>
<para>
There were some changes in PHP 5 regarding databases (MySQL and SQLite).
</para>
<para>
In PHP 5 the MySQL client libraries are not bundled, because of license
and maintenance problems. MySQL is supported with the only
change being that MySQL support is no longer enabled by
<emphasis>default</emphasis> in PHP 5. This essentially means that
PHP doesn't include the <option role="configure">--with-mysql</option>
option in the <link linkend="configuration">configure</link> line so
that you must now manually do this when compiling PHP. Windows users will
need to edit &php.ini; and enable the <filename>php_mysql.dll</filename>
DLL as in PHP 4 no such DLL existed, it was simply built into your Windows
PHP binaries.
</para>
<para>
There is also a new extension, <link linkend="ref.mysqli">MySQLi (Improved
MySQL)</link>, which is designed to work with MySQL 4.1 and above.
</para>
<para>
Since PHP 5, the SQLite extension is
built-in PHP. SQLite is an embeddable SQL database engine and is not a
client library used to connect to a big database server (like MySQL or
PostgreSQL). The SQLite library reads and writes directly to and from the
database files on disk.
</para>
</section>
<section xml:id="migration5.oop">
<title>New Object Model</title>
<para>
In PHP 5 there is a new Object Model. PHP's handling of objects has been
completely rewritten, allowing for better performance and more features.
In previous versions of PHP, objects were handled like primitive types
(for instance integers and strings). The drawback of this method was that
semantically the whole object was copied when a variable was assigned, or
passed as a parameter to a method. In the new approach, objects are
referenced by handle, and not by value (one can think of a handle as an
object's identifier).
</para>
<para>
Many PHP programmers aren't even aware of the copying quirks of the old
object model and, therefore, the majority of PHP applications will work
out of the box, or with very few modifications.
</para>
<para>
The new Object Model is documented at the <link
linkend="language.oop5">Language Reference</link>.
</para>
<para>
In PHP 5, function with the name of a class is called as a constructor
only if defined in the same class. In PHP 4, it is called also if defined
in the parent class.
</para>
<para>
See also the <link linkend="ini.zend.ze1-compatibility-mode">
zend.ze1_compatibility_mode</link> directive for compatibility with
PHP 4.
</para>
</section>
<section xml:id="migrating5.errorrep">
<title>Error Reporting</title>
<para>
As of PHP 5 the error reporting
constant <constant>E_STRICT</constant> is available, with the
value <literal>2048</literal>. When enabled, messages will be
issued to warn you about code usage which is deprecated or which
may not be future-proof.
</para>
<note>
<simpara>
<constant>E_ALL</constant> does not include <constant>E_STRICT</constant>,
so it's not enabled by default. You must explicitly set the error
reporting level to include <constant>E_STRICT</constant> in order
to see these messages.
</simpara>
</note>
<para>
See <link linkend="errorfunc.constants">Predefined Constants</link> for more information.
</para>
</section>
</appendix>
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<?xml version="1.0" encoding="utf-8"?>
<!-- $Revision$ -->
<appendix xml:id="migration51" xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink">
<title>Migrating from PHP 5.0.x to PHP 5.1.x</title>
<para>
&manual.migration.seealso;
<link linkend="migration5">5.0.x</link>,
<link linkend="migration52">5.2.x</link>,
<link linkend="migration53">5.3.x</link>,
<link linkend="migration54">5.4.x</link>,
<link linkend="migration55">5.5.x</link> and
<link linkend="migration56">5.6.x</link>.
</para>
<section xml:id="migration51.changes">
<title>Key PHP 5.1.x features</title>
<para>
Some of the key features of PHP 5.1.x include:
</para>
<itemizedlist>
<listitem>
<para>
A complete rewrite of date handling code, with improved timezone support.
</para>
</listitem>
<listitem>
<para>
Significant performance improvements compared to PHP 5.0.X.
</para>
</listitem>
<listitem>
<para>
PDO extension is now enabled by default.
</para>
</listitem>
<listitem>
<para>
Over 30 new functions in various extensions and built-in functionality.
</para>
</listitem>
<listitem>
<para>
Over 400 various bug fixes.
</para>
</listitem>
</itemizedlist>
</section>
<section xml:id="migration51.references">
<title>Changes in reference handling</title>
<itemizedlist>
<listitem>
<para>
<link linkend="migration51.references-overview">Overview</link>
</para>
</listitem>
<listitem>
<para>
<link linkend="migration51.references-fails">Code that worked under PHP
4.3.x, but now fails</link>
</para>
</listitem>
<listitem>
<para>
<link linkend="migration51.references-error">Code that worked under PHP
4.3.x, but now throws an error</link>
</para>
</listitem>
<listitem>
<para>
<link linkend="migration51.references-works">Code that failed under PHP
4.3.x, but now works</link>
</para>
</listitem>
<listitem>
<para>
<link linkend="migration51.references-didnotwork">Code that
should have worked under PHP 5.0.x</link>
</para>
</listitem>
<listitem>
<para>
<link linkend="migration51.references-warnings">Warnings that came and
went</link>
</para>
</listitem>
</itemizedlist>
<section xml:id="migration51.references-overview">
<title>Overview</title>
<para>
From the PHP script writer's point of view, the change most likely to
impact legacy code is in the way that references are handled in all PHP
versions post-dating the PHP 4.4.0 release.
</para>
<para>
Until and including PHP 4.3, it was possible to send, assign or return
variables by reference that should really be returned by value, such as
a constant, a temporary value (e.g. the result of an expression), or the
result of a function that had itself been returned by value, as here:
</para>
<informalexample>
<programlisting role="php">
<![CDATA[
<?php
$foo = "123";
function return_value() {
global $foo;
return $foo;
}
$bar = &return_value();
?>
]]>
</programlisting>
</informalexample>
<para>
Although this code would usually work as expected under PHP 4.3, in the
general case the result is undefined. The Zend Engine could not act
correctly on these values as references. This bug could and did lead to
various hard-to-reproduce memory corruption problems, particularly
where the code base was large.
</para>
<para>
In PHP 4.4.0, PHP 5.0.4 and all subsequent PHP releases, the Engine was
fixed to 'know' when the reference operation is being used on a value
that should not be referenced. The actual value is now used in such
cases, and a warning is emitted. The warning takes the form of an
<constant>E_NOTICE</constant> in PHP 4.4.0 and up, and
<constant>E_STRICT</constant> in PHP 5.0.4 and up.
</para>
<para>
Code that could potentially produce memory corruption can no longer do
so. However, some legacy code might work differently as a result.
</para>
</section>
<section xml:id="migration51.references-fails">
<title>Code that worked under PHP 4.3, but now fails</title>
<informalexample>
<programlisting role="php">
<![CDATA[
<?php
function func(&$arraykey) {
return $arraykey; // function returns by value!
}
$array = array('a', 'b', 'c');
foreach (array_keys($array) as $key) {
$y = &func($array[$key]);
$z[] =& $y;
}
var_dump($z);
?>
<]]>
</programlisting>
<para>
Running the above script under any version of PHP that pre-dates the
reference fix would produce this output:
</para>
<screen>
<![CDATA[
array(3) {
[0]=>
&string(1) "a"
[1]=>
&string(1) "b"
[2]=>
&string(1) "c"
}
]]>
</screen>
<para>
Following the reference fix, the same code would result in:
</para>
<screen>
<![CDATA[
array(3) {
[0]=>
&string(1) "c"
[1]=>
&string(1) "c"
[2]=>
&string(1) "c"
}
]]>
</screen>
</informalexample>
<para>
This is because, following the changes, <literal>func()</literal>
assigns by value. The value of <varname>$y</varname> is re-assigned,
and reference-binding is preserved from <varname>$z</varname>. Prior to
the fix, the value was assigned by reference, leading <varname>$y</varname>
to be re-bound on each assignment. The attempt to bind to a temporary
value by reference was the cause of the memory corruption.
</para>
<para>
Such code can be made to work identically in both the pre-fix and the
post-fix PHP versions. The signature of <literal>func()</literal> can
be altered to return by reference, or the reference assignment can be
removed from the result of <literal>func()</literal>.
</para>
<informalexample>
<programlisting role="php">
<![CDATA[
<?php
function func() {
return 'function return';
}
$x = 'original value';
$y =& $x;
$y = &func();
echo $x;
?>
]]>
</programlisting>
</informalexample>
<para>
In PHP 4.3 <varname>$x</varname> would be 'original value', whereas after
the changes it would be 'function return' - remember that where the
function does not return by reference, the reference assignment is
converted to a regular assignment. Again, this can be brought to a common
base, either by forcing <literal>func()</literal> to return by reference
or by eliminating the by-reference assignment.
</para>
</section>
<section xml:id="migration51.references-error">
<title>Code that worked under PHP 4.3.x, but now throws an error</title>
<informalexample>
<programlisting role="php">
<![CDATA[
<?php
class Foo {
function getThis() {
return $this;
}
function destroyThis() {
$baz =& $this->getThis();
}
}
$bar = new Foo();
$bar->destroyThis();
var_dump($bar);
?>
]]>
</programlisting>
</informalexample>
<para>
In PHP 5.0.3, <varname>$bar</varname> evaluated to <constant>NULL</constant>
instead of returning an object. That happened because
<literal>getThis()</literal> returns by value, but the value here is
assigned by reference. Although it now works in the expected way, this is
actually invalid code which will throw an <constant>E_NOTICE</constant>
under PHP 4.4 or an <constant>E_STRICT</constant> under PHP 5.0.4 and up.
</para>
</section>
<section xml:id="migration51.references-works">
<title>Code that failed under PHP 4.3.x, but now works</title>
<informalexample>
<programlisting role="php">
<![CDATA[
<?php
function &f() {
$x = "foo";
var_dump($x);
print "$x\n";
return($a);
}
for ($i = 0; $i < 3; $i++) {
$h = &f();
}
?>
]]>
</programlisting>
<para>
In PHP 4.3 the third call to <function>var_dump</function> produces
<constant>NULL</constant>, due to the memory corruption caused by
returning an uninitialized value by reference. This is valid code
in PHP 5.0.4 and up, but threw errors in earlier releases of PHP.
</para>
</informalexample>
<informalexample>
<programlisting role="php">
<![CDATA[
<?php
$arr = array('a1' => array('alfa' => 'ok'));
$arr =& $arr['a1'];
echo '-'.$arr['alfa']."-\n";
?>
]]>
</programlisting>
<para>
Until PHP 5.0.5, it wasn't possible to assign an array element by
reference in this way. It now is.
</para>
</informalexample>
</section>
<section xml:id="migration51.references-didnotwork">
<title>Code that <literal>should have worked</literal> under PHP 5.0.x</title>
<para>
There are a couple of instances of bugs reported under PHP 5.0 prior to
the reference fixes which now 'work'. However, in both cases errors are
thrown by PHP 5.1.x, because the code was invalid in the first place.
Returning values by reference using <literal>self::</literal> now works
in the general case but throws an <constant>E_STRICT</constant> warning,
and although your mileage may vary when assigning by reference to an
overloaded object, you will still see an <constant>E_ERROR</constant>
when you try it, even where the assignment itself appears to work.
</para>
</section>
<section xml:id="migration51.references-warnings">
<title>Warnings that came and went</title>
<para>
Nested calls to functions returning by reference are valid code under both
PHP 4.3.x and PHP 5.1.x, but threw an unwarranted
<constant>E_NOTICE</constant> or <constant>E_STRICT</constant> under the
intervening PHP releases.
</para>
<informalexample>
<programlisting role="php">
<![CDATA[
<?php
function & foo() {
$var = 'ok';
return $var;
}
function & bar() {
return foo();
}
$a =& bar();
echo "$a\n";
?>
]]>
</programlisting>
</informalexample>
</section>
</section>
<section xml:id="migration51.reading">
<title>Reading []</title>
<informalexample>
<programlisting role="php">
<![CDATA[
<?php
class XmlTest {
function test_ref(&$test) {
$test = "ok";
}
function test($test) { }
function run() {
$ar = array();
$this->test_ref($ar[]);
var_dump($ar);
$this->test($ar[]);
}
}
$o = new XmlTest();
$o->run();
?>
]]>
</programlisting>
</informalexample>
<para>
This should always have thrown a fatal <constant>E_ERROR</constant>,
because [] cannot be used for reading in PHP. It is invalid code in
PHP 4.4.2 and PHP 5.0.5 upward.
</para>
</section>
<section xml:id="migration51.integer-parameters">
<title>Integer values in function parameters</title>
<para>
With the advent of PHP 5.0.x, a new parameter parsing API was introduced
which is used by a large number of PHP functions. In all versions of PHP
between 5.0.x and 5.1.x, the handling of integer values was very strict and
would reject non-well formed numeric values when a PHP function expected an
integer. These checks have now been relaxed to support non-well formed
numeric strings such as " 123" and "123 ", and will no longer fail as they
did under PHP 5.0.x. However, to promote code safety and input validation,
PHP functions will now emit an <constant>E_NOTICE</constant> when such
strings are passed as integers.
</para>
</section>
<section xml:id="migration51.oop">
<title>Class and object changes</title>
<itemizedlist>
<listitem>
<para>
<link linkend="migration51.oop-functions"><literal>instanceof</literal>,
<literal>is_a()</literal>, <literal>is_subclass_of()</literal> and
<literal>catch</literal></link>
</para>
</listitem>
<listitem>
<para>
<link linkend="migration51.oop-methods">Abstract private methods</link>
</para>
</listitem>
<listitem>
<para>
<link linkend="migration51.oop-modifiers">Access modifiers in
interfaces</link>
</para>
</listitem>
<listitem>
<para>
<link linkend="migration51.oop-inheritance">Changes in inheritance
rules</link>
</para>
</listitem>
<listitem>
<para>
<link linkend="migration51.oop-constants">Class constants</link>
</para>
</listitem>
</itemizedlist>
<section xml:id="migration51.oop-functions">
<title><literal>instanceof</literal>, <literal>is_a()</literal>,
<literal>is_subclass_of()</literal> and <literal>catch</literal></title>
<para>
In PHP 5.0, <literal>is_a()</literal> was deprecated and replaced by the
<literal>instanceof</literal> operator. There were some issues with the
initial implementation of <literal>instanceof</literal>, which relied on
<literal>__autoload()</literal> to search for missing classes.
If the class was not present, <literal>instanceof</literal> would throw
a fatal <constant>E_ERROR</constant> due to the failure of
<literal>__autoload()</literal> to discover that class. The same behaviour
occurred in the <literal>catch</literal> operator and the
<literal>is_subclass_of()</literal> function, for the same reason.
</para>
<para>
None of these functions or operators call <literal>__autoload()</literal>
in PHP 5.1.x, and the <literal>class_exists()</literal> workarounds used
in code written for PHP 5.0.x, while not problematic in any way, are no
longer necessary.
</para>
</section>
<section xml:id="migration51.oop-methods">
<title>Abstract private methods</title>
<para>
Abstract private methods were supported between PHP 5.0.0 and PHP 5.0.4,
but were then disallowed on the grounds that the behaviours of
<literal>private</literal> and <literal>abstract</literal> are mutually
exclusive.
</para>
</section>
<section xml:id="migration51.oop-modifiers">
<title>Access modifiers in interfaces</title>
<para>
Under PHP 5.0, function declarations in interfaces were treated in exactly
the same way as function declarations in classes. This has not been the
case since October 2004, at which point only the <literal>public</literal>
access modifier was allowed in interface function declarations. Since
April 2005 - which pre-dates the PHP 5.0b1 release - the
<literal>static</literal> modifier has also been allowed. However, the
<literal>protected</literal> and <literal>private</literal> modifiers will
now throw an <constant>E_ERROR</constant>, as will
<literal>abstract</literal>. Note that this change should not affect your
existing code, as none of these modifiers makes sense in the context of
interfaces anyway.
</para>
</section>
<section xml:id="migration51.oop-inheritance">
<title>Changes in inheritance rules</title>
<para>
Under PHP 5.0, it was possible to have a function declaration in a derived
class that did not match the declaration of the same function in the base
class, e.g.
</para>
<informalexample>
<para>
This code will cause an <constant>E_STRICT</constant> error to be emitted
under PHP 5.1.x.
</para>
<programlisting role="php">
<![CDATA[
<?php
class Base {
function &return_by_ref() {
$r = 1;
return $r;
}
}
class Derived extends Base {
function return_by_ref() {
return 1;
}
}
?>
]]>
</programlisting>
</informalexample>
</section>
<section xml:id="migration51.oop-constants">
<title>Class constants</title>
<para>
Under PHP 5.0.x, the following code was valid:
</para>
<informalexample>
<para>
Under PHP 5.1.x, redefinition of a class constant will throw a fatal
<constant>E_ERROR</constant>.
</para>
<programlisting role="php">
<![CDATA[
<?php
class test {
const foobar = 'foo';
const foobar = 'bar';
}
?>
]]>
</programlisting>
</informalexample>
</section>
</section>
<section xml:id="migration51.extensions">
<title>Extensions</title>
<itemizedlist>
<listitem>
<para>
<link linkend="migration51.extensions-gone">Extensions that are gone
from the PHP core</link>
</para>
</listitem>
<listitem>
<para>
<link linkend="migration51.extensions-constants">Class constants in new
PHP 5.1.x extensions</link>
</para>
</listitem>
</itemizedlist>
<section xml:id="migration51.extensions-gone">
<title>Extensions that are gone from the PHP core</title>
<para>
One of the first things you're likely to notice when you download PHP 5.1.x
is that several of the older extensions have disappeared. Those extensions
that are still actively maintained are available in the PHP Extension
Community Library (PECL), at
<link xlink:href="&url.pecl;">&url.pecl;</link>.
</para>
<table>
<title>Removed extensions</title>
<tgroup cols="2">
<thead>
<row>
<entry>Extension</entry>
<entry>Alternative/Status</entry>
</row>
</thead>
<tbody>
<row>
<entry>ext/cpdf</entry>
<entry>pecl/pdflib</entry>
</row>
<row>
<entry><link linkend="ref.dbx">ext/dbx</link></entry>
<entry>pecl/dbx</entry>
</row>
<row>
<entry><link linkend="ref.dio">ext/dio</link></entry>
<entry>pecl/dio</entry>
</row>
<row>
<entry>ext/fam</entry>
<entry>Not actively maintained</entry>
</row>
<row>
<entry><link linkend="ref.ingres">ext/ingres_ii</link></entry>
<entry>pecl/ingres</entry>
</row>
<row>
<entry>ext/ircg</entry>
<entry>Not actively maintained</entry>
</row>
<row>
<entry>ext/mcve</entry>
<entry>pecl/mcve</entry>
</row>
<row>
<entry>ext/mnogosearch</entry>
<entry>Not actively maintained</entry>
</row>
<row>
<entry>ext/oracle</entry>
<entry>
<link linkend="ref.oci8">ext/oci8</link> or
<link linkend="ref.pdo-oci">ext/pdo_oci</link>
</entry>
</row>
<row>
<entry>ext/ovrimos</entry>
<entry>Not actively maintained</entry>
</row>
<row>
<entry>ext/pfpro</entry>
<entry>Not actively maintained</entry>
</row>
<row>
<entry>ext/w32api</entry>
<entry><link xlink:href="&url.pecl.package;ffi">pecl/ffi</link></entry>
</row>
<row>
<entry>ext/yp</entry>
<entry>Not actively maintained</entry>
</row>
<row>
<entry>ext/activescript</entry>
<entry>
<link xlink:href="&url.pecl.package;activescript">pecl/activescript</link>
</entry>
</row>
</tbody>
</tgroup>
</table>
<para>
Modules in PECL that are not actively maintained (i.e. have not been
supported for some time, have no active maintainer working on them
currently, and do not have any PECL package releases), are still available
in SVN at <link xlink:href="&url.php.svn;pecl">&url.php.svn;pecl</link>.
However, unreleased PHP modules are by their nature unsupported, and your
mileage may vary when attempting to install or use them.
</para>
</section>
<section xml:id="migration51.extensions-constants">
<title>Class constants in new PHP 5.1.x extensions</title>
<para>
The Zend Engine 2.1 API allows extension developers to declare class
constants in object oriented extensions. New extensions written for PHP
5.1.x, including <link linkend="ref.spl">SPL</link>,
<link linkend="intro.pdo">PDO</link>,
<link linkend="book.xmlreader">XMLReader</link> and
<link linkend="ref.datetime">date</link>, have their constants in
the format <constant>PDO::CLASS_CONSTANT</constant> rather than in the C
format <constant>PDO_CLASS_CONSTANT</constant> in order to minimise
pollution of the global namespace in PHP.
</para>
</section>
</section>
<section xml:id="migration51.datetime">
<title>Date/time support</title>
<para>
Date/time support has been fully rewritten in PHP 5.1.x, and no longer uses
the system settings to 'know' the timezone in operation. It will instead
utilize, in the following order:
</para>
<itemizedlist>
<listitem>
<para>
The timezone set using the <function>date_default_timezone_set</function>
function (if any)
</para>
</listitem>
<listitem>
<para>
The TZ environment variable (if non empty)
</para>
</listitem>
<listitem>
<para>
"magical" guess (if the operating system supports it)
</para>
</listitem>
<listitem>
<para>
If none of the above options succeeds, UTC
</para>
</listitem>
</itemizedlist>
<informalexample>
<para>
To ensure accuracy (and avoid an <constant>E_STRICT</constant> warning),
you will need to define your timezone in your <filename>php.ini</filename>
using the following format:
</para>
<para>
date.timezone = Europe/London
</para>
</informalexample>
<para>
The supported timezones are listed, in this format, in the
<link linkend="timezones">timezones appendix</link>.
</para>
<para>
Also note that <function>strtotime</function> now returns &false; on
failure, instead of -1.
</para>
</section>
<section xml:id="migration51.databases">
<title>Changes in database support</title>
<itemizedlist>
<listitem>
<para>
<link linkend="migration51.databases-pdo">PDO overview</link>
</para>
</listitem>
<listitem>
<para>
<link linkend="migration51.databases-mysql">Changes in MySQL support</link>
</para>
</listitem>
<listitem>
<para>
<link linkend="migration51.databases-sqlite">Changes in SQLite support</link>
</para>
</listitem>
</itemizedlist>
<section xml:id="migration51.databases-pdo">
<title>PDO overview</title>
<para>
<link linkend="intro.pdo">PHP Data Objects (PDO)</link> were introduced as a
PECL extension under PHP 5.0, and became part of the core PHP distribution
in PHP 5.1.x. The PDO extension provides a consistent interface for database
access, and is used alongside database-specific PDO drivers. Each driver
may also have database-specific functions of its own, but basic data
access functionality such as issuing queries and fetching data is covered
by PDO functions, using the driver named in
<function>PDO::__construct</function>.
</para>
<para>
Note that the PDO extension, and its drivers, are intended to be built as
shared extensions. This will enable straightforward driver upgrades from
PECL, without forcing you to rebuild all of PHP.
</para>
<para>
At the point of the PHP 5.1.x release, PDO is more than ready for widespread
testing and could be adopted in most situations. However, it is important
to understand that PDO and its drivers are comparatively young and may be
missing certain database-specific features; evaluate PDO carefully before
you use it in new projects.
</para>
<para>
Legacy code will generally rely on the pre-existing database extensions,
which are still maintained.
</para>
</section>
<section xml:id="migration51.databases-mysql">
<title>Changes in MySQL support</title>
<para>
In PHP 4, MySQL 3 support was built-in. With the release of PHP 5.0 there
were two MySQL extensions, named 'mysql' and 'mysqli', which were designed
to support MySQL &lt; 4.1 and MySQL 4.1 and up, respectively. With the
introduction of PDO, which provides a very fast interface to all the
database APIs supported by PHP, the PDO_MYSQL driver can support any of
the current versions (MySQL 3, 4 or 5) in PHP code written for PDO,
depending on the MySQL library version used during compilation. The older
MySQL extensions remain in place for reasons of back compatibility, but
are not enabled by default.
</para>
</section>
<section xml:id="migration51.databases-sqlite">
<title>Changes in SQLite support</title>
<para>
In PHP 5.0.x, SQLite 2 support was provided by the built-in sqlite
extension, which was also available as a PECL extension in PHP 4.3 and PHP
4.4. With the introduction of PDO, the sqlite extension doubles up to act
as a 'sqlite2' driver for PDO; it is due to this that the sqlite extension
in PHP 5.1.x has a dependency upon the PDO extension.
</para>
<para>
PHP 5.1.x ships with a number of alternative interfaces to sqlite:
</para>
<para>
The sqlite extension provides the "classic" sqlite procedural/OO API that
you may have used in prior versions of PHP. It also provides the PDO
'sqlite2' driver, which allows you to access legacy SQLite 2 databases
using the PDO API.
</para>
<para>
PDO_SQLITE provides the 'sqlite' version 3 driver. SQLite version 3 is
vastly superior to SQLite version 2, but the file formats of the two
versions are not compatible.
</para>
<para>
If your SQLite-based project is already written and working against
earlier PHP versions, then you can continue to use ext/sqlite without
problems, but will need to explicitly enable both PDO and sqlite. New
projects should use PDO and the 'sqlite' (version 3) driver, as this is
faster than SQLite 2, has improved locking concurrency, and supports both
prepared statements and binary columns natively.
</para>
<para>
You must enable PDO to use the SQLite extension. If you want to build the
PDO extension as a shared extension, then the SQLite extension must also
be built shared. The same holds true for any extension that provides a PDO
driver
</para>
</section>
</section> <!-- end of migration51.databases -->
<section xml:id="migration51.errorcheck">
<title>Checking for <constant>E_STRICT</constant></title>
<informalexample>
<para>
If you only have a single script to check, you can pick up
<constant>E_STRICT</constant> errors using PHP's commandline lint
facility:
</para>
<programlisting role="shell">
php -d error_reporting=4095 -l script_to_check.php
</programlisting>
<para>
For larger projects, the shell script below will achieve the same task:
</para>
<programlisting role="shell">
<![CDATA[
#!/bin/sh
directory=$1
shift
# These extensions are checked
extensions="php inc"
check_file ()
{
echo -ne "Doing PHP syntax check on $1 ..."
# Options:
ERRORS=`/www/php/bin/php -d display_errors=1 -d html_errors=0 -d error_prepend_string=" " -d error_append_string=" " -d error_reporting=4095 -l $1 | grep -v "No syntax errors detected"`
if test -z "$ERRORS"; then
echo -ne "OK."
else
echo -e "Errors found!\n$ERRORS"
fi
echo
}
# loop over remaining file args
for FILE in "$@" ; do
for ext in $extensions; do
if echo $FILE | grep "\.$ext$" > /dev/null; then
if test -f $FILE; then
check_file "$FILE"
fi
fi
done
done
]]>
</programlisting>
</informalexample>
</section>
</appendix>
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@ -31,15 +31,6 @@
versions in production environments.
</para>
<para>
&manual.migration.seealso;
<link linkend="migration5">5.0.x</link>,
<link linkend="migration51">5.1.x</link>,
<link linkend="migration52">5.2.x</link>,
<link linkend="migration53">5.3.x</link>,
<link linkend="migration54">5.4.x</link> and
<link linkend="migration55">5.5.x</link>.
</para>
</sect1>
</appendix>

View file

@ -31,17 +31,6 @@
be considered, and code should be tested before switching PHP versions in
production environments.
</para>
<para>
&manual.migration.seealso;
<link linkend="migration5">5.0.x</link>,
<link linkend="migration51">5.1.x</link>,
<link linkend="migration52">5.2.x</link>,
<link linkend="migration53">5.3.x</link>,
<link linkend="migration54">5.4.x</link>,
<link linkend="migration55">5.5.x</link> and
<link linkend="migration56">5.6.x</link>.
</para>
</sect1>
</appendix>

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@ -93,8 +93,7 @@
<function>set_magic_quotes_runtime</function>, along with its alias
<function>magic_quotes_runtime</function>, have been removed. They were
deprecated in PHP 5.3.0, and became effectively non-functional with the
removal of magic quotes
<link linkend="migration54.incompatible">in PHP 5.4.0</link>.
removal of magic quotes in PHP 5.4.0.
</para>
</sect3>

View file

@ -24,13 +24,6 @@
<para>
&manual.migration.seealso;
<link linkend="migration5">5.0.x</link>,
<link linkend="migration51">5.1.x</link>,
<link linkend="migration52">5.2.x</link>,
<link linkend="migration53">5.3.x</link>,
<link linkend="migration54">5.4.x</link>,
<link linkend="migration55">5.5.x</link>,
<link linkend="migration56">5.6.x</link> and
<link linkend="migration70">7.0.x</link>.
</para>
</sect1>

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@ -22,13 +22,6 @@
<para>
&manual.migration.seealso;
<link linkend="migration5">5.0.x</link>,
<link linkend="migration51">5.1.x</link>,
<link linkend="migration52">5.2.x</link>,
<link linkend="migration53">5.3.x</link>,
<link linkend="migration54">5.4.x</link>,
<link linkend="migration55">5.5.x</link>,
<link linkend="migration56">5.6.x</link>,
<link linkend="migration70">7.0.x</link> and
<link linkend="migration71">7.1.x</link>.
</para>

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@ -23,13 +23,6 @@
<para>
&manual.migration.seealso;
<link linkend="migration5">5.0.x</link>,
<link linkend="migration51">5.1.x</link>,
<link linkend="migration52">5.2.x</link>,
<link linkend="migration53">5.3.x</link>,
<link linkend="migration54">5.4.x</link>,
<link linkend="migration55">5.5.x</link>,
<link linkend="migration56">5.6.x</link>,
<link linkend="migration70">7.0.x</link>,
<link linkend="migration71">7.1.x</link> and
<link linkend="migration72">7.2.x</link>.