BEGIN {
    use strict;
    use warnings;
    print "I am here!\n";
    use Pod::Usage qw( pod2usage );
    ### Bomb if there is nothing on the command line ###
    pod2usage(2) if ( not @ARGV );
    print "I am there!\n";
    @cmd = fileparse( File::Spec->rel2abs( $0 ), '\.[^.]*' );
    $LIBPATH = File::Spec->catdir( $cmd[1], "../lib" );
    eval " use lib '$LIBPATH'";
    chdir "$LIBPATH";
    
    use Data::Dumper;
    printf "---ENV---\n%s\n", Dumper( \%ENV );
    
}
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I am here!
Usage:
    move_data.pl [options]

    Options:

     -help..........Brief help message
     -man...........Full documentation
     -config........Full path to the configuration file
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Which is what I expected, while on a Linux machine, I only get the I am here!...

Odd, works just fine for me. Maybe you should try running it in the debugger. Since the relevant code is in a BEGIN block, you need to put

        BEGIN {
            $DB::single = 1;
            ...
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in there to make sure the debugger doesn't just jump over it. Then, call

    $ perl -d move_data.pl
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from the command line and step through the source lines using n and s.