$ perl -wMstrict -CSD -e 'print "\x{FEFF}"' | hexdump -C
00000000  ef bb bf                                          |...|
$ perl -wMstrict -e 'binmode STDOUT, ":raw:encoding(UTF-8)";     print "\x{FEFF}"' | hexdump -C
00000000  ef bb bf                                          |...|
$ perl -wMstrict -e 'binmode STDOUT, ":raw:encoding(UTF-16-LE)"; print "\x{FEFF}"' | hexdump -C
00000000  ff fe                                             |..|
$ perl -wMstrict -e 'binmode STDOUT, ":raw:encoding(UTF-16-BE)"; print "\x{FEFF}"' | hexdump -C
00000000  fe ff                                             |..|
$ perl -wMstrict -e 'binmode STDOUT, ":raw:encoding(UTF-32-LE)"; print "\x{FEFF}"' | hexdump -C
00000000  ff fe 00 00                                       |....|
$ perl -wMstrict -e 'binmode STDOUT, ":raw:encoding(UTF-32-BE)"; print "\x{FEFF}"' | hexdump -C
00000000  00 00 fe ff                                       |....|