Here's a solution that works with arbitrary encodings rather than just ASCII: 
use Encode qw( decode encode );

my $input    = '...';
my $enc      = 'US-ASCII';
my $spc      = encode($enc, ' ');
my $filtered = decode($enc, encode($enc, $s, sub { $spc }));

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Encode

In reply to Re: Excluding non ascii characters by ikegami
in thread Excluding non ascii characters by millsperl

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