should also read that hint file for specific information for your
system. (Unixware users should use the svr4.sh hint file.)
+=head1 NOTE: This version is not binary compatible with Perl 5.004.
+
+For Perl 5.004 it was possible to be binary compatible with 5.003.
+Starting from Perl 5.004_50 this is no longer possible because there were
+many deep and far-reaching changes to the language internals.
+
+If you have dynamically loaded extensions that you built under perl
+5.003 or 5.004 and the so-called 'bincompat3' mode (the default mode)
+and that you wish to continue to use with perl 5.005, you may need to
+reinstall the extensions. If you wish to continue to support both 5.004
+and 5.005 on your system, you will have to move the 5.004 extensions
+over to the 5.004 architecture-dependent library. See the discussion
+below on L<"Coexistence with earlier versions of perl5.">
+
+The standard extensions supplied with Perl will be handled automatically.
+
+In a related issue, old extensions may possibly be affected by the
+changes in the Perl language in the current release. Please see
+pod/perldelta.pod for a description of what's changed.
+
=head1 Space Requirements
The complete perl5 source tree takes up about 7 MB of disk space. The
If you prefer the GNU-style configure command line interface, you can
use the supplied configure command, e.g.
- CC=gcc ./configure
+ CC=gcc ./configure.gnu
The configure script emulates a few of the more common configure
options. Try
- ./configure --help
+ ./configure.gnu --help
for a listing.
Cross compiling is not supported.
-For systems that do not distinguish the files "Configure" and
-"configure", Perl includes a copy of configure named
-configure.gnu.
+(The file is called configugre.gnu to avoid problems on systems
+that would not distinguish the files "Configure" and "configure".)
=head2 Extensions
By default, Configure will offer to build every extension which appears
to be supported. For example, Configure will offer to build GDBM_File
only if it is able to find the gdbm library. (See examples below.)
-DynaLoader, Fcntl, and IO are always built by default. Configure does
-not contain code to test for POSIX compliance, so POSIX is always built
-by default as well. If you wish to skip POSIX, you can set the
-Configure variable useposix=false either in a hint file or from the
-Configure command line. Similarly, the Opcode extension is always built
-by default, but you can skip it by setting the Configure variable
+B, DynaLoader, Fcntl, IO, and attrs are always built by default.
+Configure does not contain code to test for POSIX compliance, so POSIX
+is always built by default as well. If you wish to skip POSIX, you can
+set the Configure variable useposix=false either in a hint file or from
+the Configure command line. Similarly, the Opcode extension is always
+built by default, but you can skip it by setting the Configure variable
useopcode=false either in a hint file for from the command line.
You can learn more about each of these extensions by consulting the
In summary, here are the Configure command-line variables you can set
to turn off each extension:
+ B (Always included by default)
DB_File i_db
DynaLoader (Must always be included as a static extension)
Fcntl (Always included by default)
SDBM_File (Always included by default)
Opcode useopcode
Socket d_socket
+ Threads usethreads
+ attrs (Always included by default)
Thus to skip the NDBM_File extension, you can use
Of course, you may always run Configure interactively and select only
the extensions you want.
-Note: The DB_File module will only work with version 1.x of
-Berkeley DB. Once Berkeley DB version 2 is released, DB_File will be
-upgraded to work with it. Configure will automatically detect this
-for you and refuse to try to build DB_File with version 2.
+Note: The DB_File module will only work with version 1.x of Berkeley
+DB or newer releases of version 2. Configure will automatically detect
+this for you and refuse to try to build DB_File with version 2.
Finally, if you have dynamic loading (most modern Unix systems do)
remember that these extensions do not increase the size of your perl
The directories site_perl and site_perl/archname are empty, but are
intended to be used for installing local or site-wide extensions. Perl
-will automatically look in these directories.
+will automatically look in these directories.
In order to support using things like #!/usr/local/bin/perl5.004 after
a later version is released, architecture-dependent libraries are
stored in a version-specific directory, such as
-/usr/local/lib/perl5/archname/5.004/.
+/usr/local/lib/perl5/archname/5.004/.
Again, these are just the defaults, and can be changed as you run
Configure.
make test
make install
+Beware, though, that if you go to try to install new add-on
+extensions, they too will get installed in under '/tmp/perl5' if you
+follow this example. The next section shows one way of dealing with
+that problem.
+
=head2 Creating an installable tar archive
If you need to install perl on many identical systems, it is
cd /usr/local # Or wherever you specified as $prefix
tar xvf perl5-archive.tar
+=head2 Site-wide "Policy" settings
+
+After Configure runs, it stores a number of common site-wide "policy"
+answers (such as installation directories and the local perl contact
+person) in the Policy.sh file. If you want to build perl on another
+system using the same policy defaults, simply copy the Policy.sh file
+to the new system and Configure will use it along with the appropriate
+hint file for your system.
+
=head2 Configure-time Options
There are several different ways to Configure and build perl for your
Some users, however, may wish to further customize perl. Here are
some of the main things you can change.
-=head2 Binary Compatibility With Earlier Versions of Perl 5
+=head2 Threads
-For Perl 5.004 it was possible to be binary compatible with 5.003.
-Starting from Perl 5.005 this is no more possible because there were
-many deep and far-reaching changes to the language internals.
+On some platforms, perl5.005 can be compiled to use threads. To
+enable this, read the file README.threads, and then try
-If you have dynamically loaded extensions that you built under perl
-5.003 or 5.004 and the so-called 'bincompat3' mode (the default mode)
-and that you wish to continue to use with perl 5.005, you may need to
-reinstall the extensions.
-
-Background: starting with Perl 5.003, all functions in the Perl C
-source code have been protected by default by the prefix Perl_ (or
-perl_) so that you may link with third-party libraries without fear of
-namespace collisions. This change broke compatibility with version
-5.002, so installing 5.003 or 5.004 over 5.002 or earlier will force
-you to re-build and install all of your dynamically loadable
-extensions. (The standard extensions supplied with Perl are handled
-automatically). You can turn off this namespace protection by adding
--DNO_EMBED to your ccflags variable in config.sh.
+ sh Configure -Dusethreads
-In a related issue, old extensions may possibly be affected by the
-changes in the Perl language in the current release. Please see
-pod/perldelta.pod for a description of what's changed.
+Currently, you need to specify -Dusethreads on the Configure command
+line so that the hint files can make appropriate adjustments.
+
+The default is to compile without thread support.
=head2 Selecting File IO mechanisms
The perl source is shipped with a version of malloc that is very fast
but somewhat wasteful of space. On the other hand, your system's
-malloc() function is probably a bit slower but also a bit more frugal.
+malloc() function may be a bit slower but also a bit more frugal.
For many uses, speed is probably the most important consideration, so
the default behavior (for most systems) is to use the malloc supplied
=head1 Coexistence with earlier versions of perl5
-You can safely install the current version of perl5 and still run scripts
-under the old binaries for versions 5.003 and later ONLY. Instead of
-starting your script with #!/usr/local/bin/perl, just start it with
-#!/usr/local/bin/perl5.003 (or whatever version you want to run.)
-If you want to retain a version of Perl 5 prior to 5.003, you'll
-need to install the current version in a separate directory tree,
-since some of the architecture-independent library files have changed
-in incompatible ways.
-
-The old architecture-dependent files are stored in a version-specific
-directory (such as /usr/local/lib/perl5/sun4-sunos/5.003) so that they
-will still be accessible even after a later version is installed.
-(Note: Perl 5.000 and 5.001 did not put their architecture-dependent
-libraries in a version-specific directory. They are simply in
-/usr/local/lib/perl5/$archname. If you will not be using 5.000 or
-5.001, you may safely remove those files.)
-
-In general, the standard library files in /usr/local/lib/perl5 should
-be usable by all versions of perl5. However, the diagnostics.pm module
-uses the /usr/local/lib/perl5/pod/perldiag.pod documentation file, so
-the C<use diagnostics;> pragma and the splain script will only identify
-and explain any warnings or errors that the most recently-installed
-version of perl can generate.
-
-Most extensions will probably not need to be recompiled to use with a newer
-version of perl. If you do run into problems, and you want to continue
-to use the old version of perl along with your extension, simply move
+WARNING: The upgrade from 5.004_0x to 5.005 is going to be a bit
+tricky. See L<"Upgrading from 5.004 to 5.005"> below.
+
+In general, you can usually safely upgrade from one version of Perl (e.g.
+5.004_04) to another similar version (e.g. 5.004_05) without re-compiling
+all of your add-on extensions. You can also safely leave the old version
+around in case the new version causes you problems for some reason.
+For example, if you want to be sure that your script continues to run
+with 5.004_04, simplly replace the '#!/usr/local/bin/perl' line at the
+top of the script with the particular version you want to run, e.g.
+#!/usr/local/bin/perl5.00404.
+
+(If you are upgrading from 5.002 or earlier, beware that some of the
+standard library files have changed in incompatible ways, so you are
+probably better off starting with a fresh installation.)
+
+The standard library files in /usr/local/lib/perl5 should be usable by
+all versions of perl5 after 5.002. An exception is the diagnostics.pm
+module. Since that module uses the /usr/local/lib/perl5/pod/perldiag.pod
+documentation file, the C<use diagnostics;> pragma and the splain script
+will only identify and explain any warnings or errors that the most
+recently-installed version of perl can generate. Usually, this is not
+a problem.
+
+Most extensions will probably not need to be recompiled to use
+with a newer version of perl. Here is how it is supposed to work.
+(These examples assume you accept all the Configure defaults.)
+
+The directories searched by version 5.004_05 will be
+
+ /usr/local/lib/perl5/archname/5.00405
+ /usr/local/lib/perl5/
+ /usr/local/lib/perl5/site_perl/archname
+ /usr/local/lib/perl5/site_perl
+
+while the directories searched by version 5.004_04 are
+
+ /usr/local/lib/perl5/archname/5.00404
+ /usr/local/lib/perl5/
+ /usr/local/lib/perl5/site_perl/archname
+ /usr/local/lib/perl5/site_perl
+
+When you install an add-on extension, it gets installed into
+/usr/local/lib/perl5/site_perl/archname (if it is architecture-specific.)
+This directory is deliberately NOT version-specific so that both 5.004_04
+and 5.004_05 can use the extension.
+
+However, if you do run into problems, and you want to continue to
+use the old version of perl along with your extension, simply move
those extension files to the appropriate version directory, such as
-/usr/local/lib/perl/archname/5.003. Then Perl 5.003 will find your
-files in the 5.003 directory, and newer versions of perl will find your
-newer extension in the site_perl directory.
+/usr/local/lib/perl5/archname/5.00404. Then use your newer version of
+perl to rebuild and re-install the extension into site_perl. This way,
+Perl 5.004_04 will find your files in the 5.00404 directory, and
+newer versions of perl will find your newer extension in the site_perl
+directory.
+
+=head2 Maintaining completely separate versions
Many users prefer to keep all versions of perl in completely
separate directories. One convenient way to do this is by
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. 5.004 for all 5.004_0x 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 5.004 to 5.005
+
+Extensions compiled with versions of perl prior to 5.004_50 will need
+to be recompiled to be used with 5.004_50 and later.
+
+If you wish to continue using those extensions under 5.004_04, for
+example, then you need to move those extensions from their current
+direcotries, which are something like
+
+ /usr/local/lib/perl5/site_perl/
+ /usr/local/lib/perl5/site_perl/archname
+
+to the version-specific directory such as
+
+ /usr/local/lib/perl5/archname/5.00404
+
+as described above.
+
+Once you have moved the 5.00404 versions of the extensions out of the
+way, you may recompile and reinstall with 5.005.
+
=head1 Coexistence with perl4
You can safely install perl5 even if you want to keep perl4 around.
=head1 LAST MODIFIED
-$Id: INSTALL,v 1.28 1997/10/10 16:50:59 doughera Released $
+$Id: INSTALL,v 1.31 1998/03/03 18:08:52 doughera Released $