I think if you replace 122 below with 127, it will work. I just used 122 to demonstrate with printable characters: 
use warnings;
use strict;

my $s = 'foo bar {}{}';
$s =~ s/(.)/(ord($1) > 122) ? sprintf '\\x%x', ord($1) : $1/ge;
print "$s\n";

__END__

foo bar \x7b\x7d\x7b\x7d

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In reply to Re: How to replace extended ascii ctrs with \xnn strings? by toolic
in thread How to replace extended ascii ctrs with \xnn strings? by bulrush

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