>perl -v
This is perl, v5.8.3 built for i386-linux-thread-multi

Copyright 1987-2003, Larry Wall

Perl may be copied only under the terms of either the Artistic License or the
GNU General Public License, which may be found in the Perl 5 source kit.

Complete documentation for Perl, including FAQ lists, should be found on
this system using `man perl' or `perldoc perl'.  If you have access to the
Internet, point your browser at http://www.perl.com/, the Perl Home Page.

>cat rv
#!/usr/bin/perl -w
    use strict;
    my $rv = 42 for (1);
    print "$rv\n";
>./rv
Use of uninitialized value in concatenation (.) or string at ./rv line 4.

>perl -Mstrict  -wle'my $rv=42 for (1); print ">$rv<"'
Use of uninitialized value in concatenation (.) or string at -e line 1.
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