+ /usr/local/lib/perl5/site_perl/5.8.8
+
+ /usr/local/lib/perl5/site_perl/5.8.7
+
+ /usr/local/lib/perl5/site_perl/
+
+Note that the earlier $archname entries are now gone, but pure perl
+modules from earlier versions will still be found.
+
+This way, you can choose to share compatible extensions, but also upgrade
+to a newer version of an extension that may be incompatible with earlier
+versions, without breaking the earlier versions' installations.
+
+=head2 Maintaining completely separate versions
+
+Many users prefer to keep all versions of perl in completely
+separate directories. This guarantees that an update to one version
+won't interfere with another version. (The defaults guarantee this for
+libraries after 5.6.0, but not for executables. TODO?) One convenient
+way to do this is by using a separate prefix for each version, such as
+
+ sh Configure -Dprefix=/opt/perl5.11.2
+
+and adding /opt/perl5.11.2/bin to the shell PATH variable. Such users
+may also wish to add a symbolic link /usr/local/bin/perl so that
+scripts can still start with #!/usr/local/bin/perl.
+
+Others might share a common directory for maintenance sub-versions
+(e.g. 5.10 for all 5.10.x versions), but change directory with
+each major version.
+
+If you are installing a development subversion, you probably ought to
+seriously consider using a separate directory, since development
+subversions may not have all the compatibility wrinkles ironed out
+yet.
+
+=head2 Upgrading from 5.11.0 or earlier
+
+B<Perl 5.11.2 is binary incompatible with Perl 5.11.1 and any earlier
+Perl release.> Perl modules having binary parts
+(meaning that a C compiler is used) will have to be recompiled to be
+used with 5.11.2. If you find you do need to rebuild an extension with
+5.11.2, you may safely do so without disturbing the older
+installations. (See L<"Coexistence with earlier versions of perl 5">
+above.)
+
+See your installed copy of the perllocal.pod file for a (possibly
+incomplete) list of locally installed modules. Note that you want
+perllocal.pod, not perllocale.pod, for installed module information.
+
+=head1 Minimizing the Perl installation
+
+The following section is meant for people worrying about squeezing the
+Perl installation into minimal systems (for example when installing
+operating systems, or in really small filesystems).
+
+Leaving out as many extensions as possible is an obvious way:
+Encode, with its big conversion tables, consumes a lot of
+space. On the other hand, you cannot throw away everything. The
+Fcntl module is pretty essential. If you need to do network
+programming, you'll appreciate the Socket module, and so forth: it all
+depends on what do you need to do.
+
+In the following we offer two different slimmed down installation
+recipes. They are informative, not normative: the choice of files
+depends on what you need.
+
+Firstly, the bare minimum to run this script
+
+ use strict;
+ use warnings;
+ foreach my $f (</*>) {
+ print("$f\n");
+ }
+
+in Linux is as follows (under $Config{prefix}):
+
+ ./bin/perl
+ ./lib/perl5/5.9.3/strict.pm
+ ./lib/perl5/5.9.3/warnings.pm
+ ./lib/perl5/5.9.3/i686-linux/File/Glob.pm
+ ./lib/perl5/5.9.3/i686-linux/XSLoader.pm
+ ./lib/perl5/5.9.3/i686-linux/auto/File/Glob/Glob.so
+
+Secondly, Debian perl-base package contains the following files,
+size about 1.9MB in its i386 version:
+
+ /usr/bin/perl
+ /usr/bin/perl5.8.4
+ /usr/lib/perl/5.8
+ /usr/lib/perl/5.8.4/B.pm
+ /usr/lib/perl/5.8.4/B/Deparse.pm
+ /usr/lib/perl/5.8.4/Config.pm
+ /usr/lib/perl/5.8.4/Cwd.pm
+ /usr/lib/perl/5.8.4/Data/Dumper.pm
+ /usr/lib/perl/5.8.4/DynaLoader.pm
+ /usr/lib/perl/5.8.4/Errno.pm
+ /usr/lib/perl/5.8.4/Fcntl.pm
+ /usr/lib/perl/5.8.4/File/Glob.pm
+ /usr/lib/perl/5.8.4/IO.pm
+ /usr/lib/perl/5.8.4/IO/File.pm
+ /usr/lib/perl/5.8.4/IO/Handle.pm
+ /usr/lib/perl/5.8.4/IO/Pipe.pm
+ /usr/lib/perl/5.8.4/IO/Seekable.pm
+ /usr/lib/perl/5.8.4/IO/Select.pm
+ /usr/lib/perl/5.8.4/IO/Socket.pm
+ /usr/lib/perl/5.8.4/POSIX.pm
+ /usr/lib/perl/5.8.4/Socket.pm
+ /usr/lib/perl/5.8.4/XSLoader.pm
+ /usr/lib/perl/5.8.4/auto/Cwd/Cwd.bs
+ /usr/lib/perl/5.8.4/auto/Cwd/Cwd.so
+ /usr/lib/perl/5.8.4/auto/Data/Dumper/Dumper.bs
+ /usr/lib/perl/5.8.4/auto/Data/Dumper/Dumper.so
+ /usr/lib/perl/5.8.4/auto/DynaLoader/DynaLoader.a
+ /usr/lib/perl/5.8.4/auto/DynaLoader/autosplit.ix
+ /usr/lib/perl/5.8.4/auto/DynaLoader/dl_expandspec.al
+ /usr/lib/perl/5.8.4/auto/DynaLoader/dl_find_symbol_anywhere.al
+ /usr/lib/perl/5.8.4/auto/DynaLoader/dl_findfile.al
+ /usr/lib/perl/5.8.4/auto/DynaLoader/extralibs.ld
+ /usr/lib/perl/5.8.4/auto/Fcntl/Fcntl.bs
+ /usr/lib/perl/5.8.4/auto/Fcntl/Fcntl.so
+ /usr/lib/perl/5.8.4/auto/File/Glob/Glob.bs
+ /usr/lib/perl/5.8.4/auto/File/Glob/Glob.so
+ /usr/lib/perl/5.8.4/auto/IO/IO.bs
+ /usr/lib/perl/5.8.4/auto/IO/IO.so
+ /usr/lib/perl/5.8.4/auto/POSIX/POSIX.bs
+ /usr/lib/perl/5.8.4/auto/POSIX/POSIX.so
+ /usr/lib/perl/5.8.4/auto/POSIX/autosplit.ix
+ /usr/lib/perl/5.8.4/auto/POSIX/load_imports.al
+ /usr/lib/perl/5.8.4/auto/Socket/Socket.bs
+ /usr/lib/perl/5.8.4/auto/Socket/Socket.so
+ /usr/lib/perl/5.8.4/lib.pm
+ /usr/lib/perl/5.8.4/re.pm
+ /usr/share/doc/perl-base
+ /usr/share/doc/perl/AUTHORS.gz
+ /usr/share/doc/perl/Documentation
+ /usr/share/doc/perl/README.Debian.gz
+ /usr/share/doc/perl/changelog.Debian.gz
+ /usr/share/doc/perl/copyright
+ /usr/share/man/man1/perl.1.gz
+ /usr/share/perl/5.8
+ /usr/share/perl/5.8.4/AutoLoader.pm
+ /usr/share/perl/5.8.4/Carp.pm
+ /usr/share/perl/5.8.4/Carp/Heavy.pm
+ /usr/share/perl/5.8.4/Exporter.pm
+ /usr/share/perl/5.8.4/Exporter/Heavy.pm
+ /usr/share/perl/5.8.4/File/Spec.pm
+ /usr/share/perl/5.8.4/File/Spec/Unix.pm
+ /usr/share/perl/5.8.4/FileHandle.pm
+ /usr/share/perl/5.8.4/Getopt/Long.pm
+ /usr/share/perl/5.8.4/IO/Socket/INET.pm
+ /usr/share/perl/5.8.4/IO/Socket/UNIX.pm
+ /usr/share/perl/5.8.4/IPC/Open2.pm
+ /usr/share/perl/5.8.4/IPC/Open3.pm
+ /usr/share/perl/5.8.4/List/Util.pm
+ /usr/share/perl/5.8.4/Scalar/Util.pm
+ /usr/share/perl/5.8.4/SelectSaver.pm
+ /usr/share/perl/5.8.4/Symbol.pm
+ /usr/share/perl/5.8.4/Text/ParseWords.pm
+ /usr/share/perl/5.8.4/Text/Tabs.pm
+ /usr/share/perl/5.8.4/Text/Wrap.pm
+ /usr/share/perl/5.8.4/attributes.pm
+ /usr/share/perl/5.8.4/base.pm
+ /usr/share/perl/5.8.4/bytes.pm
+ /usr/share/perl/5.8.4/bytes_heavy.pl
+ /usr/share/perl/5.8.4/constant.pm
+ /usr/share/perl/5.8.4/fields.pm
+ /usr/share/perl/5.8.4/integer.pm
+ /usr/share/perl/5.8.4/locale.pm
+ /usr/share/perl/5.8.4/overload.pm
+ /usr/share/perl/5.8.4/strict.pm
+ /usr/share/perl/5.8.4/utf8.pm
+ /usr/share/perl/5.8.4/utf8_heavy.pl
+ /usr/share/perl/5.8.4/vars.pm
+ /usr/share/perl/5.8.4/warnings.pm
+ /usr/share/perl/5.8.4/warnings/register.pm
+
+A nice trick to find out the minimal set of Perl library files you will
+need to run a Perl program is
+
+ perl -e 'do "prog.pl"; END { print "$_\n" for sort keys %INC }'
+
+(this will not find libraries required in runtime, unfortunately, but
+it's a minimal set) and if you want to find out all the files you can
+use something like the below
+
+ strace perl -le 'do "x.pl"' 2>&1 | perl -nle '/^open\(\"(.+?)"/ && print $1'
+
+(The 'strace' is Linux-specific, other similar utilities include 'truss'
+and 'ktrace'.)
+
+=head2 C<-DNO_MATHOMS>
+
+If you configure perl with C<-Accflags=-DNO_MATHOMS>, the functions from
+F<mathoms.c> will not be compiled in. Those functions are no longer used
+by perl itself; for source compatibility reasons, though, they weren't
+completely removed.