Hex dump

A hex dump is a textual representation of bytes in a file, and hexdump is a command-line tool that can dump bytes from a file in a variety of formats, including hexadecimal, octal and ASCII.

Hex dump is a draft programming task. It is not yet considered ready to be promoted as a complete task, for reasons that should be found in its talk page.

hexdump's canonical format displays, on each line:

• a byte offset in hexadecimal,
• up to 16 bytes in hexadecimal, separated by spaces, with an extra space between the 8th and 9th byte,
• the same 16 bytes interpreted as ASCII characters, with non-printing and non-ascii characters replaced with a dot (.), surrounded by pipes (|).

The last line of output shows a final byte count, also in hexadecimal.

For example, the string "Rosetta Code is a programming chrestomathy site 😀." encoded in UTF-16 (little-endian - the first two bytes are the byte order mark), displayed in the canonical format is:

00000000  ff fe 52 00 6f 00 73 00  65 00 74 00 74 00 61 00  |..R.o.s.e.t.t.a.|
00000010  20 00 43 00 6f 00 64 00  65 00 20 00 69 00 73 00  | .C.o.d.e. .i.s.|
00000020  20 00 61 00 20 00 70 00  72 00 6f 00 67 00 72 00  | .a. .p.r.o.g.r.|
00000030  61 00 6d 00 6d 00 69 00  6e 00 67 00 20 00 63 00  |a.m.m.i.n.g. .c.|
00000040  68 00 72 00 65 00 73 00  74 00 6f 00 6d 00 61 00  |h.r.e.s.t.o.m.a.|
00000050  74 00 68 00 79 00 20 00  73 00 69 00 74 00 65 00  |t.h.y. .s.i.t.e.|
00000060  20 00 3d d8 00 de 2e 00                           | .=.....|
00000068

Task

Implement a hexdump-like program that:

• outputs in the canonical format,
• takes an optional offset in bytes from which to start,
• takes an optional length in bytes after which it will stop.

Demonstrate your implementation by showing the canonical hex dump of the example above, plus any other examples you find useful.

Stretch

xxd is another command-line tool similar to hexdump. It offers a binary mode where bytes are displayed in bits instead of hexadecimal.

Implement a binary mode. For this task, in binary mode, the example above should be displayed like this:

00000000  11111111 11111110 01010010 00000000 01101111 00000000  |..R.o.|
00000006  01110011 00000000 01100101 00000000 01110100 00000000  |s.e.t.|
0000000c  01110100 00000000 01100001 00000000 00100000 00000000  |t.a. .|
00000012  01000011 00000000 01101111 00000000 01100100 00000000  |C.o.d.|
00000018  01100101 00000000 00100000 00000000 01101001 00000000  |e. .i.|
0000001e  01110011 00000000 00100000 00000000 01100001 00000000  |s. .a.|
00000024  00100000 00000000 01110000 00000000 01110010 00000000  | .p.r.|
0000002a  01101111 00000000 01100111 00000000 01110010 00000000  |o.g.r.|
00000030  01100001 00000000 01101101 00000000 01101101 00000000  |a.m.m.|
00000036  01101001 00000000 01101110 00000000 01100111 00000000  |i.n.g.|
0000003c  00100000 00000000 01100011 00000000 01101000 00000000  | .c.h.|
00000042  01110010 00000000 01100101 00000000 01110011 00000000  |r.e.s.|
00000048  01110100 00000000 01101111 00000000 01101101 00000000  |t.o.m.|
0000004e  01100001 00000000 01110100 00000000 01101000 00000000  |a.t.h.|
00000054  01111001 00000000 00100000 00000000 01110011 00000000  |y. .s.|
0000005a  01101001 00000000 01110100 00000000 01100101 00000000  |i.t.e.|
00000060  00100000 00000000 00111101 11011000 00000000 11011110  | .=...|
00000066  00101110 00000000                                      |..|
00000068

Other hexdump/xxd features and a command line interface to your program are optional.

FreeBASIC

Code adapted from https://github.com/jlaasonen/hexfile

The code is from Jussi Laasonen (https://jlaasonen.me)

'Usage:  hexfile [-i <first index>] <file>

Const bytesPerLine = 16
Const tabWidth = 3
Const fileIndexWidth = 8
Const firstIndex = 1

Const asciiLowerBound = 31
Const asciiUpperBound = 127
Const emptyByte = "  "
Const emptyAsciiByte = " "
Const nonAsciiByte = "."

Enum Keys Explicit
    Up = &H48FF
    PageUp = &H49FF
    Down = &H50FF
    PageDown = &H51FF
    Home = &H47FF
    End_ = &H4FFF
    Esc = 27
End Enum

Sub GetLine(Byval fileIndex As Longint, Byval fileNumber As Integer, bytes() As Ubyte)
    Dim bytesread As Uinteger
    
    If Get(#fileNumber,fileIndex,bytes(), ,bytesread) = 0 And bytesread > 0 Then
        Redim Preserve bytes(bytesread)
    Else
        Erase bytes
    End If
End Sub

Function ByteToAscii(Byval byte_ As Ubyte) As String
    Return Iif(byte_ > asciiLowerBound And byte_ < asciiUpperBound, Chr(byte_), nonAsciiByte)
End Function

Function MakeLine(Byval firstIndexDisplay As Longint, Byval fileIndex As Longint, bytes() As Ubyte) As String
    If Ubound(bytes) < Lbound(bytes) Then Return "" End If
    
    Dim hexBytes As String = ""
    Dim asciiBytes As String = ""
    
    For byteIndex As Integer = Lbound(bytes) To Lbound(bytes) + bytesPerLine - 1
        If byteIndex <= Ubound(bytes) Then
            Dim byte_ As Ubyte = bytes(byteIndex)
            asciiBytes += ByteToAscii(byte_)
            hexBytes += Hex(byte_, 2)
        Else
            asciiBytes += emptyAsciiByte
            hexBytes += emptyByte
        End If
        
        hexBytes += Iif(byteIndex = (bytesPerLine\2)-1, "  ", " ")
    Next
    
    Dim displayIndex As Const Longint = fileIndex - firstIndex + firstIndexDisplay
    Return Space(1) + Hex(displayIndex,fileIndexWidth) + Space(tabWidth) +_
    hexBytes + Space(tabWidth-1) + asciiBytes
End Function

Sub DumpInteractive(Byval fileNumber As Integer, Byval firstIndexDisplay As Longint)
    Dim consoleDimensions As Integer = Width()
    Dim linesPerPage As Integer = Hiword(consoleDimensions)
    Dim bytesPerPage As Integer = bytesPerline * linesPerPage
    
    Dim numberOfFullLines As Longint = (Lof(fileNumber)-1) \ bytesPerLine
    Dim lastLineIndex As Longint = numberOfFullLines * bytesPerLine + firstIndex
    Dim lastPageIndex As Longint = lastLineIndex - bytesPerPage + bytesPerLine
    If lastPageIndex < firstIndex Then lastPageIndex = firstIndex End If
    
    Cls
    
    Dim input_ As Long
    Dim fileIndex As Longint = firstIndex
    
    Do
        Locate 1,1,0
        For lineNumber As Integer = 1 To linesPerPage
            Dim lineIndex As Longint = fileIndex + (lineNumber-1)*bytesPerLine
            Redim bytes(bytesPerLine) As Ubyte
            GetLine(lineIndex, fileNumber, bytes())
            Dim lineText As String = MakeLine(firstIndexDisplay, lineIndex, bytes())
            If lineNumber = linesPerPage Then
                Print lineText;
            Else
                Print lineText
            End If
        Next
        
        input_ = Getkey
        Select Case As Const input_
        Case Keys.PageUp
            fileIndex -= bytesPerPage
        Case Keys.Up
            fileIndex -= bytesPerLine
        Case Keys.PageDown
            fileIndex += bytesPerPage
        Case Keys.Down
            fileIndex += bytesPerLine
        Case Keys.Home
            fileIndex = firstIndex
        Case Keys.End_
            fileIndex = lastPageIndex
        End Select
        
        If fileIndex < firstIndex Then fileIndex = firstIndex
        If fileIndex > lastPageIndex Then fileIndex = lastPageIndex
    Loop Until input_ = Keys.Esc
End Sub

Sub PrintUsage()
    Const firstColumn = 4
    Const secondColumn = 12
    
    Dim controls(0 To ..., 2) As String = {_
    {"Down", "Scroll down one line."},_
    {"Up", "Scroll up one line."},_
    {"PgDown", "Show next page."},_
    {"PgUp", "Show previos page."},_
    {"End", "Jump to the end of the file."},_
    {"Home", "Jump to the beginning of the file."},_
    {"Esc", "Quit."}_
    }
    
    Print "hexfile - a simple commandline hexdumper"
    Print "  (c) 2021-2023 Jussi Laasonen. Licensed under the MIT license."
    Print "  See https://github.com/jlaasonen/hexfile for full license."
    Print !"\nUsage: hexfile [-i <first index>] <file>"
    Print !"\nDisplays an interactive hex dump the file."
    Print !"\nControls:"
    
    For row As Integer = Lbound(controls) To Ubound(controls)
        Print Tab(firstColumn);controls(row,0);Tab(secondColumn);controls(row,1)
    Next
    
    Print !"\nOptions:"
    Print "  -i <first index>"
    Print "    Starts the displayed file index from the given index. Defaults to 0."
    Print "    The value is expected in decimal format. For binary, octal or hexadecimal"
    Print "    Use prefix &B, &O or &H respectively."
End Sub

Const fileIndexArgument = "-i"

Dim fileName As String = ""
Dim firstIndexDisplay As Longint = 0

If __fb_argc__ = 2 Then
    fileName = Command(1)
Elseif __fb_argc__ = 4  And Command(1) = fileIndexArgument Then
    firstIndexDisplay = Vallng(Command(2))
    fileName = Command(3)
End If

Dim fileNumber As Long = Freefile

If fileName = "" Then
    PrintUsage()
Elseif Open(fileName For Binary Access Read As #fileNumber) = 0 Then
    DumpInteractive(fileNumber, firstIndexDisplay)
    Close(fileNumber)
Else
    Print "Failed to open file '" + fileName + "'."
End If

hexfile Windows terminal

Julia

function baseddump(data, base = 16; offset = 0, len = -1)
    @assert base in [2, 10, 16] "display base $base not supported"
    len = len < 0 ? length(data) : min(len, length(data))
    bytes = data[begin+offset:len]
    fullchunksize = base == 16 ? 16 : base == 10 ? 10 : 6
    halflen, pos = fullchunksize ÷ 2, 0
    for chunk in Iterators.partition(bytes, fullchunksize)
        chunklen, vlen = length(chunk), base == 16 ? 49 : base == 10 ? 41 : 55
        values = map(n -> string(n, base=base, 
           pad = base == 16 ? 2 : base == 10 ? 3 : 8) * " ", chunk)
        vstr = join(values[begin:begin+min(halflen, chunklen)-1])
        if chunklen > halflen
            vstr *= " "^(base!=2) * join(values[begin+halflen:end])
        end
        cstr = prod(map(n -> n < 128 && isprint(Char(n)) ? Char(n) : '.', chunk))
        println(string(pos, base= 16, pad = 8) * " " * rpad(vstr, vlen) * "|" * cstr * "|")
        pos += fullchunksize
    end
end
hexdump(data; offset = 0, len = -1) = baseddump(data; offset, len)
xxd(data; offset = 0, len = -1) = baseddump(data, 2; offset, len)
decdump(data; offset = 0, len = -1) = baseddump(data, 10; offset, len)

const tstr = b"\xff\xfeRosetta Code is a programming chrestomathy site 😀."
const utf16 = vcat(b"\xff\xfe", reinterpret(UInt8, transcode(UInt16, tstr[begin+2:end])))
print("hexdump of 16-bit "), display(String(tstr))
hexdump(utf16)
print("\nxxd of 16-bit "), display(String(tstr))
xxd(utf16)
print("\ndecdump of 16-bit"), display(String(tstr))
decdump(utf16)

Output:

hexdump of 16-bit "\xff\xfeRosetta Code is a programming chrestomathy site 😀."
00000000 ff fe 52 00 6f 00 73 00  65 00 74 00 74 00 61 00 |..R.o.s.e.t.t.a.|
00000010 20 00 43 00 6f 00 64 00  65 00 20 00 69 00 73 00 | .C.o.d.e. .i.s.|
00000020 20 00 61 00 20 00 70 00  72 00 6f 00 67 00 72 00 | .a. .p.r.o.g.r.|
00000030 61 00 6d 00 6d 00 69 00  6e 00 67 00 20 00 63 00 |a.m.m.i.n.g. .c.|
00000040 68 00 72 00 65 00 73 00  74 00 6f 00 6d 00 61 00 |h.r.e.s.t.o.m.a.|
00000050 74 00 68 00 79 00 20 00  73 00 69 00 74 00 65 00 |t.h.y. .s.i.t.e.|
00000060 20 00 3d d8 00 de 2e 00                          | .=.....|        

xxd of 16-bit "\xff\xfeRosetta Code is a programming chrestomathy site 😀."
00000000 11111111 11111110 01010010 00000000 01101111 00000000  |..R.o.|
00000006 01110011 00000000 01100101 00000000 01110100 00000000  |s.e.t.|
0000000c 01110100 00000000 01100001 00000000 00100000 00000000  |t.a. .|
00000012 01000011 00000000 01101111 00000000 01100100 00000000  |C.o.d.|
00000018 01100101 00000000 00100000 00000000 01101001 00000000  |e. .i.|
0000001e 01110011 00000000 00100000 00000000 01100001 00000000  |s. .a.|
00000024 00100000 00000000 01110000 00000000 01110010 00000000  | .p.r.|
0000002a 01101111 00000000 01100111 00000000 01110010 00000000  |o.g.r.|
00000030 01100001 00000000 01101101 00000000 01101101 00000000  |a.m.m.|
00000036 01101001 00000000 01101110 00000000 01100111 00000000  |i.n.g.|
0000003c 00100000 00000000 01100011 00000000 01101000 00000000  | .c.h.|
00000042 01110010 00000000 01100101 00000000 01110011 00000000  |r.e.s.|
00000048 01110100 00000000 01101111 00000000 01101101 00000000  |t.o.m.|
0000004e 01100001 00000000 01110100 00000000 01101000 00000000  |a.t.h.|
00000054 01111001 00000000 00100000 00000000 01110011 00000000  |y. .s.|
0000005a 01101001 00000000 01110100 00000000 01100101 00000000  |i.t.e.|
00000060 00100000 00000000 00111101 11011000 00000000 11011110  | .=...|
00000066 00101110 00000000                                      |..|

decdump of 16-bit"\xff\xfeRosetta Code is a programming chrestomathy site 😀."
00000000 255 254 082 000 111  000 115 000 101 000 |..R.o.s.e.|
0000000a 116 000 116 000 097  000 032 000 067 000 |t.t.a. .C.|
00000014 111 000 100 000 101  000 032 000 105 000 |o.d.e. .i.|
0000001e 115 000 032 000 097  000 032 000 112 000 |s. .a. .p.|
00000028 114 000 111 000 103  000 114 000 097 000 |r.o.g.r.a.|
00000032 109 000 109 000 105  000 110 000 103 000 |m.m.i.n.g.|
0000003c 032 000 099 000 104  000 114 000 101 000 | .c.h.r.e.|
00000046 115 000 116 000 111  000 109 000 097 000 |s.t.o.m.a.|
00000050 116 000 104 000 121  000 032 000 115 000 |t.h.y. .s.|
0000005a 105 000 116 000 101  000 032 000 061 216 |i.t.e. .=.|
00000064 000 222 046 000                          |....|

Phix

with javascript_semantics
sequence utf16 = #FEFF & "Rosetta Code is a programming chrestomathy site " & {#d83d,#DE00,'.'}
function to2(integer i) return {and_bits(i,#FF),floor(i/#100)} end function
constant string s = flatten(apply(utf16,to2),"")
--or: (javascript incompatible)
--constant string s = get_text(filename) -- (if you have a suitable premade one to hand)

procedure hexdump(string s, integer start=0, finish=-1, bool bHex=true, bFinalSize=true)
    s = s[start+1..finish]
    integer ll = iff(bHex?16:6), ls = length(s)
    string hbfmt = iff(bHex?"%02x ":"%08b "),
           lnfmt = "%08x %s |%-" & sprintf("%d",ll) & "s|\n"
    sequence lines = split_by(s,ll)
    for l in lines do
        string hb = " ", ascii = ""
        for i,b in l do
            hb &= sprintf(hbfmt,b)
            if b<' ' or b>'~' then b = '.' end if
            ascii &= b
            if i=8 then hb &= ' ' end if
        end for
        hb = pad_tail(hb,iff(bHex?50:55))
        printf(1,lnfmt,{start,hb,ascii})
        start += length(l)
    end for
    if bFinalSize then
        printf(1,"%08x\n",{ls})
    end if
end procedure

printf(1,"Hexadecimal:\n")
hexdump(s)
printf(1,"\nBinary:\n")
hexdump(s,bHex:=false)

Although not shown, the intention is the outer calling code (last four lines) could call hexdump() to display one page at a time, with appropriate user input, and/or read s in chunks and pass a file offset instead of or as well as start, finish.

Output:

Hexadecimal:
00000000  FF FE 52 00 6F 00 73 00  65 00 74 00 74 00 61 00  |..R.o.s.e.t.t.a.|
00000010  20 00 43 00 6F 00 64 00  65 00 20 00 69 00 73 00  | .C.o.d.e. .i.s.|
00000020  20 00 61 00 20 00 70 00  72 00 6F 00 67 00 72 00  | .a. .p.r.o.g.r.|
00000030  61 00 6D 00 6D 00 69 00  6E 00 67 00 20 00 63 00  |a.m.m.i.n.g. .c.|
00000040  68 00 72 00 65 00 73 00  74 00 6F 00 6D 00 61 00  |h.r.e.s.t.o.m.a.|
00000050  74 00 68 00 79 00 20 00  73 00 69 00 74 00 65 00  |t.h.y. .s.i.t.e.|
00000060  20 00 3D D8 00 DE 2E 00                           | .=.....        |
00000068

Binary:
00000000  11111111 11111110 01010010 00000000 01101111 00000000  |..R.o.|
00000006  01110011 00000000 01100101 00000000 01110100 00000000  |s.e.t.|
0000000C  01110100 00000000 01100001 00000000 00100000 00000000  |t.a. .|
00000012  01000011 00000000 01101111 00000000 01100100 00000000  |C.o.d.|
00000018  01100101 00000000 00100000 00000000 01101001 00000000  |e. .i.|
0000001E  01110011 00000000 00100000 00000000 01100001 00000000  |s. .a.|
00000024  00100000 00000000 01110000 00000000 01110010 00000000  | .p.r.|
0000002A  01101111 00000000 01100111 00000000 01110010 00000000  |o.g.r.|
00000030  01100001 00000000 01101101 00000000 01101101 00000000  |a.m.m.|
00000036  01101001 00000000 01101110 00000000 01100111 00000000  |i.n.g.|
0000003C  00100000 00000000 01100011 00000000 01101000 00000000  | .c.h.|
00000042  01110010 00000000 01100101 00000000 01110011 00000000  |r.e.s.|
00000048  01110100 00000000 01101111 00000000 01101101 00000000  |t.o.m.|
0000004E  01100001 00000000 01110100 00000000 01101000 00000000  |a.t.h.|
00000054  01111001 00000000 00100000 00000000 01110011 00000000  |y. .s.|
0000005A  01101001 00000000 01110100 00000000 01100101 00000000  |i.t.e.|
00000060  00100000 00000000 00111101 11011000 00000000 11011110  | .=...|
00000066  00101110 00000000                                      |..    |
00000068

Python

"""Display bytes in a file like hexdump or xxd."""
import abc
import math
from io import BufferedIOBase
from itertools import islice
from typing import Iterable
from typing import Iterator
from typing import Sequence
from typing import Tuple
from typing import TypeVar


READ_SIZE = 2048


class Formatter(abc.ABC):
    """Base class for hex dump formatters."""

    @abc.abstractmethod
    def __call__(self, data: Sequence[int]) -> str:
        """"""

    @property
    @abc.abstractmethod
    def bytes_per_line(self) -> int:
        """"""


class CanonicalFormatter(Formatter):
    bytes_per_line = 16

    def __call__(self, data: Sequence[int]) -> str:
        assert len(data) <= 16
        hex = f"{bytes(data[:8]).hex(' ')}  {bytes(data[8:]).hex(' ')}".ljust(48)
        ascii_ = "".join(chr(b) if b > 31 and b < 127 else "." for b in data)
        return f"{hex}  |{ascii_}|"


class BinaryFormatter(Formatter):
    bytes_per_line = 6

    def __call__(self, data: Sequence[int]) -> str:
        assert len(data) <= 6
        bits = " ".join(bin(b)[2:].rjust(8, "0") for b in data).ljust(53)
        ascii_ = "".join(chr(b) if b > 31 and b < 127 else "." for b in data)
        return f"{bits}  |{ascii_}|"


canonicalFormatter = CanonicalFormatter()
binaryFormatter = BinaryFormatter()

T = TypeVar("T")


def group(it: Iterable[T], n: int) -> Iterator[Tuple[T, ...]]:
    """Split iterable _it_ in to groups of size _n_.

    The last group might contain less than _n_ items.
    """
    _it = iter(it)
    while True:
        g = tuple(islice(_it, n))
        if not g:
            break
        yield g


def hex_dump(
    f: BufferedIOBase,
    *,
    skip: int = 0,
    length: int = math.inf,  # type: ignore
    format: Formatter = canonicalFormatter,
) -> Iterator[str]:
    """Generate a textual representation of bytes in _f_, one line at a time."""
    f.seek(skip)
    offset = 0
    byte_count = 0
    previous_line = ""
    identical_chunk = False

    while byte_count < length:
        # Read at most READ_SIZE bytes at a time.
        data = f.read(READ_SIZE)

        # Stop if we've run out of data.
        if not data:
            break

        # Discard excess bytes if we've overshot length.
        if byte_count + len(data) > length:
            data = data[: length - byte_count]

        # One line per chunk
        for chunk in group(data, format.bytes_per_line):
            line = format(chunk)
            if previous_line == line:
                if identical_chunk is False:
                    identical_chunk = True
                    yield "*"
            else:
                previous_line = line
                identical_chunk = False
                yield f"{offset:0>8x}  {line}"

            offset += format.bytes_per_line
            byte_count += len(chunk)

    # Final byte count
    yield f"{byte_count:0>8x}"


if __name__ == "__main__":
    import argparse

    parser = argparse.ArgumentParser(
        prog="hex_dump.py",
        description="Display bytes in a file.",
    )

    parser.add_argument(
        "file",
        type=argparse.FileType(mode="rb"),
        metavar="FILE",
        help="target file to dump",
    )

    parser.add_argument(
        "-b",
        "--binary",
        action="store_true",
        help="display bytes in binary instead of hex",
    )

    parser.add_argument(
        "-s",
        "--skip",
        type=int,
        default=0,
        help="skip SKIP bytes from the beginning",
    )

    parser.add_argument(
        "-n",
        "--length",
        type=int,
        default=math.inf,
        help="read up to LENGTH bytes",
    )

    args = parser.parse_args()
    formatter = binaryFormatter if args.binary else canonicalFormatter

    for line in hex_dump(
        args.file,
        format=formatter,
        skip=args.skip,
        length=args.length,
    ):
        print(line)

Output:

$ python hex_dump.py example_utf16.txt

00000000  ff fe 52 00 6f 00 73 00  65 00 74 00 74 00 61 00  |..R.o.s.e.t.t.a.|
00000010  20 00 43 00 6f 00 64 00  65 00 20 00 69 00 73 00  | .C.o.d.e. .i.s.|
00000020  20 00 61 00 20 00 70 00  72 00 6f 00 67 00 72 00  | .a. .p.r.o.g.r.|
00000030  61 00 6d 00 6d 00 69 00  6e 00 67 00 20 00 63 00  |a.m.m.i.n.g. .c.|
00000040  68 00 72 00 65 00 73 00  74 00 6f 00 6d 00 61 00  |h.r.e.s.t.o.m.a.|
00000050  74 00 68 00 79 00 20 00  73 00 69 00 74 00 65 00  |t.h.y. .s.i.t.e.|
00000060  20 00 3d d8 00 de 2e 00                           | .=.....|
00000068

$ python hex_dump.py example_utf16.txt -b

00000000  11111111 11111110 01010010 00000000 01101111 00000000  |..R.o.|
00000006  01110011 00000000 01100101 00000000 01110100 00000000  |s.e.t.|
0000000c  01110100 00000000 01100001 00000000 00100000 00000000  |t.a. .|
00000012  01000011 00000000 01101111 00000000 01100100 00000000  |C.o.d.|
00000018  01100101 00000000 00100000 00000000 01101001 00000000  |e. .i.|
0000001e  01110011 00000000 00100000 00000000 01100001 00000000  |s. .a.|
00000024  00100000 00000000 01110000 00000000 01110010 00000000  | .p.r.|
0000002a  01101111 00000000 01100111 00000000 01110010 00000000  |o.g.r.|
00000030  01100001 00000000 01101101 00000000 01101101 00000000  |a.m.m.|
00000036  01101001 00000000 01101110 00000000 01100111 00000000  |i.n.g.|
0000003c  00100000 00000000 01100011 00000000 01101000 00000000  | .c.h.|
00000042  01110010 00000000 01100101 00000000 01110011 00000000  |r.e.s.|
00000048  01110100 00000000 01101111 00000000 01101101 00000000  |t.o.m.|
0000004e  01100001 00000000 01110100 00000000 01101000 00000000  |a.t.h.|
00000054  01111001 00000000 00100000 00000000 01110011 00000000  |y. .s.|
0000005a  01101001 00000000 01110100 00000000 01100101 00000000  |i.t.e.|
00000060  00100000 00000000 00111101 11011000 00000000 11011110  | .=...|
00000066  00101110 00000000                                      |..|
00000068

Wren

Library: Wren-seq

Library: Wren-fmt

This is only tested on Linux (Ubuntu 22.04).

As my text editor always adds a trailing \n, the method removes this before dumping the remainder.

import "io" for File
import "./seq" for Lst
import "./fmt" for Fmt

class DumpUtf16 {
    static hex(fileName, start, length) {
        var bytes = File.read(fileName).bytes.toList[0..-3] // remove final \n
        var bc = bytes.count
        if (start >= bc) Fiber.abort("Starting point is invalid.")
        if (length < 1 || length > bc - start) length = bc - start
        bytes = bytes[start...start+length]
        var rows = Lst.chunks(bytes, 16)
        var rc = rows.count
        for (i in 0...rc) {
            var line = rows[i]
            var lc = line.count
            var ascii = List.filled(lc, 0)
            for (b in 0...lc) {
                var c = line[b]
                if (c >= 32 && c < 127) {
                    ascii[b] = String.fromByte(c)
                } else {
                    ascii[b] = "."
                }
            }
            var text = "|" + ascii.join() + (" " * (16-lc)) + "|"
            if (i < rc-1) {
                Fmt.print("$08x  $02x  $02x  $s", i * 16, line[0..7], line[8..-1], text)
            } else if (lc <= 8){
                var extra = "   " * (8-lc)
                Fmt.print("$08x  $02x$s  $23s $s", i * 16, line[0..-1], extra, " ", text)
            } else {
                var extra = "   " * (16-lc)
                Fmt.print("$08x  $02x  $02x$s  $s", i * 16, line[0..7], line[8..-1], extra, text)
            }
        }
        Fmt.print("$08x", bytes.count)
    }

    static hex(fileName, start) { hex(fileName, start, -1) }
    static hex(fileName)        { hex(fileName, 0, -1)     }

    static bin(fileName, start, length) {
        var bytes = File.read(fileName).bytes.toList[0..-3] // remove final \n
        var bc = bytes.count
        if (start >= bc) Fiber.abort("Starting point is invalid.")
        if (length < 1 || length > bc - start) length = bc - start
        bytes = bytes[start...start+length]
        var rows = Lst.chunks(bytes, 6)
        var rc = rows.count
        for (i in 0...rc) {
            var line = rows[i]
            var lc = line.count
            var ascii = List.filled(lc, 0)
            for (b in 0...lc) {
                var c = line[b]
                if (c >= 32 && c < 127) {
                    ascii[b] = String.fromByte(c)
                } else {
                    ascii[b] = "."
                }
            }
            var text = "|" + ascii.join() + (" " * (6-lc)) + "|"
            if (i < rc-1) {
                Fmt.print("$08x  $08b  $s", i * 6, line, text)
            } else {
                var extra = "         " * (6-lc)
                Fmt.print("$08x  $08b$s  $s", i * 6, line, extra, text)
            }
        }
        Fmt.print("$08x", bytes.count)
    }

    static bin(fileName, start) { bin(fileName, start, -1) }  
    static bin(fileName)        { bin(fileName, 0, -1)     }
}

var fileName = "example_utf16.txt"
DumpUtf16.hex(fileName)
System.print()
DumpUtf16.bin(fileName)

Output:

00000000  ff fe 52 00 6f 00 73 00  65 00 74 00 74 00 61 00  |..R.o.s.e.t.t.a.|
00000010  20 00 43 00 6f 00 64 00  65 00 20 00 69 00 73 00  | .C.o.d.e. .i.s.|
00000020  20 00 61 00 20 00 70 00  72 00 6f 00 67 00 72 00  | .a. .p.r.o.g.r.|
00000030  61 00 6d 00 6d 00 69 00  6e 00 67 00 20 00 63 00  |a.m.m.i.n.g. .c.|
00000040  68 00 72 00 65 00 73 00  74 00 6f 00 6d 00 61 00  |h.r.e.s.t.o.m.a.|
00000050  74 00 68 00 79 00 20 00  73 00 69 00 74 00 65 00  |t.h.y. .s.i.t.e.|
00000060  20 00 3d d8 00 de 2e 00                           | .=.....        |
00000068

00000000  11111111 11111110 01010010 00000000 01101111 00000000  |..R.o.|
00000006  01110011 00000000 01100101 00000000 01110100 00000000  |s.e.t.|
0000000c  01110100 00000000 01100001 00000000 00100000 00000000  |t.a. .|
00000012  01000011 00000000 01101111 00000000 01100100 00000000  |C.o.d.|
00000018  01100101 00000000 00100000 00000000 01101001 00000000  |e. .i.|
0000001e  01110011 00000000 00100000 00000000 01100001 00000000  |s. .a.|
00000024  00100000 00000000 01110000 00000000 01110010 00000000  | .p.r.|
0000002a  01101111 00000000 01100111 00000000 01110010 00000000  |o.g.r.|
00000030  01100001 00000000 01101101 00000000 01101101 00000000  |a.m.m.|
00000036  01101001 00000000 01101110 00000000 01100111 00000000  |i.n.g.|
0000003c  00100000 00000000 01100011 00000000 01101000 00000000  | .c.h.|
00000042  01110010 00000000 01100101 00000000 01110011 00000000  |r.e.s.|
00000048  01110100 00000000 01101111 00000000 01101101 00000000  |t.o.m.|
0000004e  01100001 00000000 01110100 00000000 01101000 00000000  |a.t.h.|
00000054  01111001 00000000 00100000 00000000 01110011 00000000  |y. .s.|
0000005a  01101001 00000000 01110100 00000000 01100101 00000000  |i.t.e.|
00000060  00100000 00000000 00111101 11011000 00000000 11011110  | .=...|
00000066  00101110 00000000                                      |..    |
00000068