$ perl -Mstrict -Mwarnings -E ' my $x = "\x{ef}\x{bb}\x{bf}123,,,\x{ef}\x{bb}\x{bf}456"; say "Full string:"; system "echo $x | hexdump -Cv"; $x =~ s/\xef\xbb\xbf//g; say "All BOM sequences removed:"; system "echo $x | hexdump -Cv"; ' Full string: 00000000 ef bb bf 31 32 33 2c 2c 2c ef bb bf 34 35 36 0a |...123,,,...456.| 00000010 All BOM sequences removed: 00000000 31 32 33 2c 2c 2c 34 35 36 0a |123,,,456.| 0000000a