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       Apache2::compat -- 1.0 backward compatibility functions deprecated in

	 # either add at the very beginning of
	 use Apache2::compat;
	 # or httpd.conf
	 PerlModule Apache2::compat

	 # override and	restore	compat functions colliding with	mp2 API
	 my ($local_port, $local_addr) = sockaddr_in($c->local_addr);

       "Apache2::compat" provides mod_perl 1.0 compatibility layer and can be
       used to smooth the transition process to	mod_perl 2.0.

       It includes functions that have changed their API or were removed in
       mod_perl	2.0. If	your code uses any of those functions, you should load
       this module at the server startup, and everything should	work as	it did
       in 1.0. If it doesn't please report the bug, but	before you do that
       please make sure	that your code does work properly under	mod_perl 1.0.

       However,	remember, that it's implemented	in pure	Perl and not C,
       therefore its functionality is not optimized and	it's the best to try
       to port your code not to	use deprecated functions and stop using	the
       compatibility layer.

Compatibility Functions	Colliding with mod_perl	2.0 API
       Most of the functions provided by Apache2::compat don't interfere with
       mod_perl	2.0 API. However there are several functions which have	the
       same name in the	mod_perl 1.0 and mod_perl 2.0 API, accept the same
       number of arguments, but	either the arguments themselves	aren't the
       same or the return values are different.	For example the	mod_perl 1.0

	 require Socket;
	 my $sockaddr_in = $c->local_addr;
	 my ($local_port, $local_addr) = Socket::sockaddr_in($sockaddr_in);

       should be adjusted to be:

	 require Apache2::Connection;
	 require APR::SockAddr;
	 my $sockaddr =	$c->local_addr;
	 my ($local_port, $local_addr) = ($sockaddr->port, $sockaddr->ip_get);

       to work under mod_perl 2.0.

       As you can see in mod_perl 1.0 API local_addr() was returning a
       SOCKADDR_IN object (see the Socket perl manpage), in mod_perl 2.0 API
       it returns an "APR::SockAddr" object, which is a	totally	different
       beast. If Apache2::compat overrides the function	"local_addr()" to be
       back-compatible with mod_perl 1.0 API. Any code that relies on this
       function	to work	as it should under mod_perl 2.0	will be	broken.
       Therefore the solution is not to	override "local_addr()"	by default.
       Instead a special API is	provided which overrides colliding functions
       only when needed	and which can be restored when no longer needed. So
       for example if you have code from mod_perl 1.0:

	 my ($local_port, $local_addr) = Socket::sockaddr_in($c->local_addr);

       and you aren't ready to port it to to use the mp2 API:

	 my ($local_port, $local_addr) = ($c->local_addr->port,

       you could do the	following:

	 my ($local_port, $local_addr) = Socket::sockaddr_in($c->local_addr);

       Notice that you need to restore the API as soon as possible.

       Both "override_mp2_api()" and "restore_mp2_api()" accept	a list of
       functions to operate on.

   Available Overridable Functions
       At the moment the following colliding functions are available for


Use in CPAN Modules
       The short answer: Do not	use "Apache2::compat" in CPAN modules.

       The long	answer:

       "Apache2::compat" is useful during the mod_perl 1.0 code	porting.
       Though remember that it's implemented in	pure Perl. In certain cases it
       overrides mod_perl 2.0 methods, because their API is very different and
       doesn't map 1:1 to mod_perl 1.0.	So if anything,	not under user's
       control,	loads "Apache2::compat"	user's code is forced to use the
       potentially slower method. Which	is quite bad.

       Some users may choose to	keep using "Apache2::compat" in	production and
       it may perform just fine. Other users will choose not to	use that
       module, by porting their	code to	use mod_perl 2.0 API. However it
       should be users'	choice whether to load this module or not and not to
       be enforced by CPAN modules.

       If you port your	CPAN modules to	work with mod_perl 2.0,	you should
       follow the porting Perl and XS module guidelines.

       Users that are stuck with CPAN modules preloading "Apache2::compat",
       can prevent this	from happening by adding

	 $INC{'Apache2/'} = __FILE__;

       at the very beginning of	their But this will	most certainly
       break the module	that needed this module.

       You should be reading the mod_perl 1.0 API docs for usage of the
       methods and functions in	this package, since what this module is	doing
       is providing a backwards	compatibility and it makes no sense to
       duplicate documentation.

       Another important document to read is: Migrating	from mod_perl 1.0 to
       mod_perl	2.0 which covers all mod_perl 1.0 constants, functions and
       methods that have changed in mod_perl 2.0.

See Also
       mod_perl	2.0 documentation.

       mod_perl	2.0 and	its core modules are copyrighted under The Apache
       Software	License, Version 2.0.

       The mod_perl development	team and numerous contributors.

perl v5.32.1		  work::mod_perl-2.0.11::docs::api::Apache2::compat(3)

NAME | Synopsis | Description | Compatibility Functions Colliding with mod_perl 2.0 API | Use in CPAN Modules | API | See Also | Copyright | Authors

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