You can also supply a shell script config.over to over-ride Configure's
guesses. It will get loaded up at the very end, just before config.sh
is created. You have to be careful with this, however, as Configure
-does no checking that your changes make sense.
+does no checking that your changes make sense. See the section on
+changing the installation directory for an example.
=item config.h
./perl op/groups.t
+B<NOTE>: one possible reason for errors is that some external programs
+may be broken due to the combination of your environment and the way
+C<make test> exercises them. This may happen for example if you have
+one or more of these environment variables set:
+C<LC_ALL LC_CTYPE LANG>. In certain UNIXes especially the non-English
+locales are known to cause programs to exhibit mysterious errors.
+If you have any of the above environment variables set, please try
+C<setenv LC_ALL C> or <LC_ALL=C;export LC_ALL>, for C<csh>-style and
+C<Bourne>-style shells, respectively, from the command line and then
+retry C<make test>. If the tests then succeed, you may have a broken
+program that is confusing the testing. Please run the troublesome test
+by hand as shown above and see whether you can locate the program.
+Look for things like:
+C<exec, `backquoted command`, system, open("|...")> or C<open("...|")>.
+All these mean that Perl is trying to run some external program.
=head1 INSTALLING PERL5
=head1 make install
The standard library files in F</usr/local/lib/perl5>
should be useable by all versions of perl5.
-Most extensions will not need to be recompiled to use with a newer
+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
those extension files to the appropriate version directory, such as
files in the 5.002 directory, and newer versions of perl will find your
newer extension in the site_perl directory.
+Some users may prefer to keep all versions of perl in completely
+separate directories. One convenient way to do this is by
+using a separate prefix for each version, such as
+
+ sh Configure -Dprefix=/opt/perl5.002
+
+and adding /opt/perl5.002/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.
+
=head1 Coexistence with perl4
You can safely install perl5 even if you want to keep perl4 around.