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perl -e '$x="\xe9"; $y="\x{00e9}"; print "\\xe9 eq \\x00e9\n" if ($x e +q $y)' # output is: \xe9 eq \x00e9
perl -e 'binmode STDOUT, ":utf8"; print "\xe9"' | xxd # output is: 0000000: c3a9 ..