I have installed Perl 5.10.0 on my Linux box to be available together
with the vendor supplied Perl 5.8.1. When running programs under
mod_perl, the old Perl version is utilized.
How can I make mod_perl use Perl 5.10.0? Can mod_perl be configured so I
can select Perl version on-the-fly?
--
Gunnar Hjalmarsson
Email: http://www.gunnar.cc/cgi-bin/contact.pl
Quoth Gunnar Hjalmarsson
> I have installed Perl 5.10.0 on my Linux box to be available together
> with the vendor supplied Perl 5.8.1. When running programs under
> mod_perl, the old Perl version is utilized.
>
> How can I make mod_perl use Perl 5.10.0? Can mod_perl be configured so I
> can select Perl version on-the-fly?
5.10 is not binary-compatible with 5.8, so you will need to rebuild
mod_perl against 5.10. AIUI, mod_perl needs to be rebuilt against a new
version of perl anyway, as it does a lot of poking around in
undocumented parts of perls guts.
Ben
Gunnar Hjalmarsson
> I have installed Perl 5.10.0 on my Linux box to be available together
> with the vendor supplied Perl 5.8.1. When running programs under
> mod_perl, the old Perl version is utilized.
>
> How can I make mod_perl use Perl 5.10.0?
Recompile & reinstall mod_perl.
> Can mod_perl be configured so
> I can select Perl version on-the-fly?
No, the Apache module is linked to libperl, so it's specific to that Perl
for the reason that an XS module is - libperl exports a different set of
public symbols from one version to the next, and hides the differences
behind an API that's almost entirely cpp macros.
If you're looking for a more performant CGI replacement, you might look
at FastCGI instead. The cost in terms of IPC between Apache and the app
server are minimal, and like mod_perl it's a persistent environment, but
like CGI, you simply use the #! line to choose a language interpreter.
sherm-
--
My blog: http://shermspace.blogspot.com
Cocoa programming in Perl: http://camelbones.sourceforge.net
Ben Morrow
> Quoth Gunnar Hjalmarsson
>> I have installed Perl 5.10.0 on my Linux box to be available together
>> with the vendor supplied Perl 5.8.1. When running programs under
>> mod_perl, the old Perl version is utilized.
>>
>> How can I make mod_perl use Perl 5.10.0? Can mod_perl be configured so I
>> can select Perl version on-the-fly?
>
> 5.10 is not binary-compatible with 5.8, so you will need to rebuild
> mod_perl against 5.10. AIUI, mod_perl needs to be rebuilt against a new
> version of perl anyway, as it does a lot of poking around in
> undocumented parts of perls guts.
That appears to no longer be the case - mod_perl 2.0.4 was released just a
couple days ago, and one of the listed changes is that "it works with 5.10."
sherm--
--
My blog: http://shermspace.blogspot.com
Cocoa programming in Perl: http://camelbones.sourceforge.net
Sherman Pendley wrote:
> Gunnar Hjalmarsson
>> I have installed Perl 5.10.0 on my Linux box to be available together
>> with the vendor supplied Perl 5.8.1. When running programs under
>> mod_perl, the old Perl version is utilized.
>>
>> How can I make mod_perl use Perl 5.10.0?
>
> Recompile & reinstall mod_perl.
Yep, it proved to be that simple.
>> Can mod_perl be configured so I can select Perl version on-the-fly?
>
> No, the Apache module is linked to libperl, so it's specific to that Perl
> for the reason that an XS module is - libperl exports a different set of
> public symbols from one version to the next, and hides the differences
> behind an API that's almost entirely cpp macros.
I noticed that /usr/lib/httpd/modules/mod_perl.so was overwritten during
the installation; guess that's part of it...
> If you're looking for a more performant CGI replacement, you might look
> at FastCGI instead. The cost in terms of IPC between Apache and the app
> server are minimal, and like mod_perl it's a persistent environment, but
> like CGI, you simply use the #! line to choose a language interpreter.
Maybe I should have a look at FastCGI. Thanks for the tip!
And thanks both Ben and Sherman for your help.
--
Gunnar Hjalmarsson
Email: http://www.gunnar.cc/cgi-bin/contact.pl
Quoth Sherman Pendley
> Ben Morrow
>
> > Quoth Gunnar Hjalmarsson
> >> I have installed Perl 5.10.0 on my Linux box to be available together
> >> with the vendor supplied Perl 5.8.1. When running programs under
> >> mod_perl, the old Perl version is utilized.
> >>
> >> How can I make mod_perl use Perl 5.10.0? Can mod_perl be configured so I
> >> can select Perl version on-the-fly?
> >
> > 5.10 is not binary-compatible with 5.8, so you will need to rebuild
> > mod_perl against 5.10. AIUI, mod_perl needs to be rebuilt against a new
> > version of perl anyway, as it does a lot of poking around in
> > undocumented parts of perls guts.
>
> That appears to no longer be the case - mod_perl 2.0.4 was released just a
> couple days ago, and one of the listed changes is that "it works with 5.10."
Read what I said again. I said you will need to *rebuild* mod_perl
against 5.10: attempting to use a version built against 5.8 with perl
5.10 definitely won't work (this applies generally to any XS module).
The fact that versions <2.0.4 won't work with 5.10 even then I didn't
address (because I didn't know :) ).
Ben
Ben Morrow
> Quoth Sherman Pendley
>> Ben Morrow
>>
>> > Quoth Gunnar Hjalmarsson
>> >> I have installed Perl 5.10.0 on my Linux box to be available together
>> >> with the vendor supplied Perl 5.8.1. When running programs under
>> >> mod_perl, the old Perl version is utilized.
>> >>
>> >> How can I make mod_perl use Perl 5.10.0? Can mod_perl be configured so I
>> >> can select Perl version on-the-fly?
>> >
>> > 5.10 is not binary-compatible with 5.8, so you will need to rebuild
>> > mod_perl against 5.10. AIUI, mod_perl needs to be rebuilt against a new
>> > version of perl anyway, as it does a lot of poking around in
>> > undocumented parts of perls guts.
>>
>> That appears to no longer be the case - mod_perl 2.0.4 was released just a
>> couple days ago, and one of the listed changes is that "it works with 5.10."
>
> Read what I said again.
What you said makes no sense when taken at face value.
Ordinary XS modules are not binary-compatible, and need to be rebuilt - but
that's *always* the case, and it's not the result of using any undocumented
calls. Mod_perl does use undocumented calls, but it needed to be ported as
a result of that, not simply rebuilt.
I chose the most charitable interpretation that made sense - that you're
aware of the situation and simply mistyped "rebuild" when you were actually
referring to the porting effort.
sherm--
--
My blog: http://shermspace.blogspot.com
Cocoa programming in Perl: http://camelbones.sourceforge.net
Quoth Sherman Pendley
> Ben Morrow
> > Quoth Sherman Pendley
> >> Ben Morrow
> >> >
> >> > 5.10 is not binary-compatible with 5.8, so you will need to rebuild
> >> > mod_perl against 5.10. AIUI, mod_perl needs to be rebuilt against a new
> >> > version of perl anyway, as it does a lot of poking around in
> >> > undocumented parts of perls guts.
> >>
> >> That appears to no longer be the case - mod_perl 2.0.4 was released
> >> just a couple days ago, and one of the listed changes is that "it
> >> works with 5.10."
> >
> > Read what I said again.
>
> What you said makes no sense when taken at face value.
>
> Ordinary XS modules are not binary-compatible, and need to be rebuilt - but
> that's *always* the case, and it's not the result of using any undocumented
> calls. Mod_perl does use undocumented calls, but it needed to be ported as
> a result of that, not simply rebuilt.
OK, perhaps I should be clearer.
Perl versions 5.8.1 through 5.8.8 were considered 'binary-compatible' by
p5p. Most XS modules built against 5.8.1 will work correctly with 5.8.8
without rebuilding. This is not true of mod_perl: since it uses
undocumented calls, it requires rebuilding for *any* change in perl
version, even one advertised by p5p as 'binary-compatible'.
Perl version 5.10 is considered by p5p to break binary compatibility.
All XS modules, mod_perl included, will need to be rebuilt. Perl
versions 5.10.x will, almost certainly, be binary-compatible with
5.10.0, so again modules *other* than mod_perl won't need to be rebuilt.
In my original reply I confused the '5.10 is binary-incompatible with
5.8' and the 'mod_perl is never binary-compatible under any change in
perl version' parts of the above.
> I chose the most charitable interpretation that made sense - that you're
> aware of the situation and simply mistyped "rebuild" when you were actually
> referring to the porting effort.
Thank you for your charity :), but I wasn't and didn't. The
clarification is appreciated.
Ben