Shortest hex dumping program

Question

Challenge

Create a console program to display each byte of a file.

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Winning

Since this is code-golf, fewest bytes wins.

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Rules

• Program must be a console application, meaning that it will be ran from some sort of command-line interpreter;
• Every byte must be uppercase hexadecimal, separated by a space, and it must be 2 digits; (put number 0 before it if it has 1 digit)
• File must be read using IO or alternative, and not hard-coded;
• File path must be specified as a command-line argument or a user prompt (like STDIN);
• No loopholes please;

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Example

test.txt (ends with LF)

Hello World!

$ ./hexdump.exe test.txt
48 65 6C 6C 6F 20 57 6F 72 6C 64 21 0A

Answer 1

C (gcc) on *nix, 73 71 bytes

i;main(c,v)int**v;{for(c=open(v[1],0);read(c,&i,1);printf("%02X ",i));}

Try it online! Test suite

-2 bytes thanks to Johan du Toit

This relies on O_RDONLY == 0 and on int_one == 1 where int int_one; *(char*)&int_one = 1;.

Answer 2

PowerShell, 45 40 bytes

"$(gc $args -ra|% *ay|%{'{0:X2}'-f+$_})"

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-5 bytes thanks to mazzy

Answer 3

PHP, 60 59 54 bytes

<?=wordwrap(bin2hex(implode(file($argv[1]))),2,' ',1);

• -1 byte thanks to manassehkatz
• -5 bytes thanks to Blackhole

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Answer 4

Ruby, 26 bytes

$<.bytes{|b|$><<"%02X "%b}

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Answer 5

Java 11, 156 154 bytes

import java.nio.file.*;interface M{static void main(String[]a)throws Exception{for(int b:Files.readAllBytes(Path.of(a[0])))System.out.printf("%02X ",b);}}

-2 bytes thanks to @Holger.

Try it online by using ./.input.tio as argument file-path, which will have a given input as file-content.

Explanation:

import java.nio.file.*;        // Required import for Files and Paths
interface M{                   // Class
  static void main(String[]a)  //  Mandatory main method
      throws Exception{        //  With mandatory thrown clause for the readAllBytes builtin
                                         a[0]    // Get the first argument
                                 Path.of(    )   // Get the file using that argument as path
              Files.readAllBytes(             )  // Get all bytes from this file
    for(int b:                                 ) // Loop over each of them:
      System.out.printf(                         //  And print the current byte
                        "%02X ",b);}}            //  As uppercase hexadecimal with leading 0
                                                 //  and trailing space as delimiter

Answer 6

Perl 5 (-aF//), 23 bytes

printf"%02X ",ord for@F

TIO

Answer 7

Python 3, 59 bytes

-11 bytes thanks to Mostly Harmless!

-8 bytes thanks to James K Polk!

-24 bytes thanks to Blue!

print(' '.join('%02X'%ord(i)for i in open(input()).read()))

Try it online!

This is pretty straightforward; it opens a filename given as input on STDIN, reads it, converts each character to its ASCII value, converts each number to hex, strips off the "0x" that precedes hexademical values in Python, pads the value with a zero if necessary, then joins the values together with spaces.

Answer 8

APL (Dyalog Unicode), 16 bytes

Anonymous tacit prefix function. Returns (and implicitly prints, if the value isn't otherwise consumed) a two-row matrix with the top 4 bits represented as a decimal number 0–15 in the top row and the bottom 4 bits similarly represented in the bottom row. That is, the matrix has as many columns as the file has bytes.

16 16⊤83 ¯1∘⎕MAP

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⎕MAP map the argument filename to an array
∘ with parameters:
¯1 the entire length of the file
83 read as 8-bit integers

16 16⊤ convert (anti-base) to 2-position hexadecimal

Answer 9

Bash,  33  23 bytes

...with a lot of help:
-3 thanks to manatwork
-4 thanks to spuck
-3 thanks to Nahuel Fouilleul

echo `xxd -c1 -p -u $1`

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Note that the TIO link above uses input - we can write files locally, so this shows it working as a program taking a file path.

Answer 10

Kotlin, 130 127 104 93 92 bytes

fun main(a:Array<String>){java.io.File(a[0]).readBytes().forEach{print("%02X ".format(it))}}

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Edit: -11 bytes thanks to @ChrisParton

Edit: Working TIO

Edit: -1 byte thanks to @KevinCruijssen

Answer 11

Dart, 140 134 bytes

import'dart:io';main(a){print(new File(a[0]).readAsBytesSync().map((n)=>n.toRadixString(16).toUpperCase().padLeft(2,'0')).join(' '));}

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-6 bytes because I forgot to reduce variable names

Answer 12

Haskell, 145 143 bytes

import System.Environment
import Text.Printf
import Data.ByteString
main=getArgs>>=Data.ByteString.readFile.(!!0)>>=mapM_(printf"%02X ").unpack

Answer 13

Rust, 141 bytes (contributed version)

use std::{io::*,fs::*,env::*};fn main(){for x in File::open(args().nth(1).unwrap()).unwrap().bytes(){print!("{:02X} ",x.unwrap())}println!()}

Rust, 151 bytes (original version)

fn main(){std::io::Read::bytes(std::fs::File::open(std::env::args().nth(1).unwrap()).unwrap()).map(|x|print!("{:02X} ",x.unwrap())).count();println!()}

Answer 14

bash+Stax, 6+4+1=11 bytes

This is complete theory craft at this point. You can't actually run this. If everything works according to its spec this would work, but not everything does yet.

The bash script is

]<$1

and the stax program must be compiled and saved to ] is

╛↕ßú┼_

Set your character set to ISO 8859-1 (Windows-1252 won't work here) and go

Unpacked and explained

_          push all input as a single array
F          run the rest of the program for each element of the array
 |H        write the hex of the byte to standard output
 |         write a space to standard output

Answer 15

Emojicode, 186 162 bytes

📦files🏠🏁🍇🔂b🍺📇🐇📄🆕🔡👂🏼❗️❗️🍇👄📫🍪🔪🔡🔢b❗️➕256 16❗️1 2❗️🔤 🔤🍪❗️❗️🍉🍉

Try it online here.

Ungolfed:

📦 files 🏠  💭 Import the files package into the default namespace
🏁 🍇  💭 Main code block
🔂 b  💭 For each b in ...
  🍺  💭 (ignoring IO errors)
  📇 🐇 📄  💭 ... the byte representation of the file ...
  🆕 🔡 👂🏼  💭 ... read from user input:
  ❗️ ❗️ 🍇
    👄  💭 Print ...
    📫  💭 ... in upper case (numbers in bases > 10 are in lower case) ...
    🍪  💭 ... the concatenation of:
      🔪 🔡 🔢 b ❗️ ➕ 256  💭 b + 256 (this gives the leading zero in case the hex representation of b is a single digit) ...
              16  💭 ... represented in hexadecimal ...
           ❗️
         1 2  💭 ... without the leading one,
      ❗️
      🔤 🔤  💭 ... and a space
    🍪
    ❗️❗️
  🍉
🍉

Answer 16

Perl 6, 45 bytes

@*ARGS[0].IO.slurp(:bin).list.fmt('%02X').say

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• @*ARGS[0] is the first command-line argument.
• .IO turns that (presumed) filename into an IO::Path object.
• .slurp(:bin) reads the entire file into a Buf buffer of bytes. (Without the :bin the file contents would be returned as a Unicode string.)
• .list returns a list of the byte values from the buffer.
• .fmt('%02X') is a List method that formats the elements of the list using the given format string, then joins them with spaces. (Convenient!)
• .say prints that string.

Answer 17

Node.js, 118 bytes

console.log([...require("fs").readFileSync(process.argv[2])].map(y=>(y<16?0:"")+y.toString(16).toUpperCase()).join` `)

What the result looks like:

Btw the content of test.txt in the example is as follows:

做乜嘢要輸出大楷姐，搞到要加番toUpperCase()去轉番，咁就13byte啦。

(Why on earth is upper-case output necessary. I had to add the conversion with toUpperCase(), and that cost 13 bytes.)

Answer 18

D, 98 Bytes

import std;void main(string[]s){File(s[1]).byChunk(9).joiner.each!(a=>writef("%02X ",a.to!byte));}

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Answer 19

Python 3, 75 bytes

Mostly a copy of Maxwell's python 2 answer.

import sys
print(' '.join('%02X'%b for b in open(sys.argv[1],'rb').read()))

Answer 20

Racket, 144 bytes

This submission does output a trailing space, and no trailing newline. Let me know if this is considered a loophole :)

(command-line #:args(f)(for([b(call-with-input-file f port->bytes)])(printf"~a "(string-upcase(~r b #:base 16 #:min-width 2 #:pad-string"0")))))

Cleaned up

(command-line #:args (f)
 (for ([b (call-with-input-file f port->bytes)])
   (printf "~a "
           (string-upcase
            (~r b #:base 16 #:min-width 2 #:pad-string "0")))))

Answer 21

Forth (gforth), 71 bytes

: f slurp-file hex 0 do dup c@ 0 <# # # #> type space 1+ loop ;
1 arg f

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TIO has 3 arg in the last line because TIO passes "-e bye" to the command line parser before passing in the code

Code Explanation

: f             \ start a function definition
  slurp-file    \ open the file indicated by the string on top of the stack,
                \ then put its contents  in a new string on top of the stack
  hex           \ set the interpreter to base 16
  0 do          \ loop from 0 to file-length - 1 (inclusive)
    dup c@      \ get the character value from the address on top of the stack
    0 <# # # #> \ convert to a double-length number then convert to a string of length 2
    type        \ output the created string 
    space       \ output a space 
    1+          \ add 1 to the current address value
  loop          \ end the loop
;               \ end the word definition
1 arg f         \ get the filename from the first command-line argument and call the function

Answer 22

Javascript, 155 bytes

for(b=WScript,a=new ActiveXObject("Scripting.FileSystemObject").OpenTextFile(b.Arguments(0));;b.echo(('0'+a.read(1).charCodeAt(0).toString(16)).slice(-2)))

Answer 23

VBScript, 143 bytes

set a=CreateObject("Scripting.FileSystemObject").OpenTextFile(WScript.Arguments(0)):while 1 WScript.echo(right("0"+Hex(Asc(a.read(1))),2)):wend

Answer 24

Wolfram Language (Mathematica), 94 89 bytes

Print@ToUpperCase@StringRiffle@IntegerString[BinaryReadList@Last@$ScriptCommandLine,16,2]

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The code is quite self-explanatory because of the long command names. It should be read mostly from right to left:

$ScriptCommandLine       is a list of {scriptname, commandlinearg1, commandlinearg2, ...}
Last@...                 extracts the last command-line argument
BinaryReadList@...       reads the named file into a list of bytes
IntegerString[...,16,2]  converts each byte to a 2-digit hex string (lowercase)
StringRiffle@...         converts this list of strings into a single string with spaces
ToUpperCase@...          converts the string to uppercase
Print@...                prints the result to stdout

Answer 25

Gema, 45 characters

?=@fill-right{00;@radix{10;16;@char-int{?}}} 

Sample run:

bash-5.0$ gema '?=@fill-right{00;@radix{10;16;@char-int{?}}} ' <<< 'Hello World!'
48 65 6C 6C 6F 20 57 6F 72 6C 64 21 0A 

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Answer 26

Pyth, 12 bytes

jdcr1.Hjb'w2

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Takes input as user prompt (no way to access command-line arguments AFAIK).

jd           # join on spaces
  c        2 # chop into pieces of length 2
   r1        # convert to uppercase
     .H      # convert to hex string, interpreting as base 256 (*)
       jb    # join on newlines
         '   # read file as list of lines
          w  # input()

(*) I'm not 100% sure if this is intended, but one base 256 digit (as in, one character), will always convert into exactly 2 hex digits, eliminating the need to pad with zeroes.

Answer 27

C# .NET Framework 4.7.2 - 235 213 203 191 175 140 bytes

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using System.IO;class P{static void Main(string[]a){foreach(var b in File.ReadAllBytes(a[0])){System.Console.Write(b.ToString("X2")+" ");}}}

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using System;
using System.IO;

namespace hexdump
{
    class Program
    {
        static void Main(string[] args)
        {
            // Read the bytes of the file
            byte[] bytes = File.ReadAllBytes(args[0]);

            // Loop through all the bytes and show them
            foreach (byte b in bytes)
            {
                // Show the byte converted to hexadecimal
                Console.Write(b.ToString("X2") + " ");
            }
        }
    }
}

Answer 28

05AB1E, 18 bytes

IvyÇh2j' 0.:' Jvy?

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Explanation:

IvyÇh2j' 0.:' Jvy?
Iv                 Loop through each character in input
  y                Push current character
   Ç               ASCII value
    h              Convert to hexadecimal
     2j            Pad with at least 2 spaces
       ' 0.:       Replace all spaces with 0s
            ' J    Add space to end
               vy? Convert to string and print
IvyÇh2j' 0.:' Jvy?

Answer 29

Free Pascal, 81 B

var c:char;begin while not EOF do begin read(c);write(hexStr(ord(c),2):3)end end.

Note, output has a leading blank and no trailing newline:
48 65 6C 6C 6F 20 57 6F 72 6C 64 21 0A

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−3 B: By default the FPC (FreePascal Compiler) has the “FPC compiler compatibility mode” selected. When compiling in FPC’s “ISO standard compiler compatibility mode” the file buffer variables (here specifically input^) and “low-level” I/O routines like get become available. The following code needs to be compiled with fpc ‑MISO sourceCode.pas:

begin while not EOF do begin write(hexStr(ord(input^),2):3);get(input)end end.

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−10 B: Furthermore, if input was guaranteed to be non-empty, we can use a repeat … until … loop instead of the bulky while … do begin … end:

begin repeat write(hexStr(ord(input^),2):3);get(input)until EOF end.