Magic Bytes

Get magic bytes using PHP

function magic_bytes($path, $position = 0, $bytes = 4)
{
    if (!file_exists($path)) {
        return null;
    }
    $handle = fopen($path, 'rb');
    fseek($handle, $position);
    $bytes = bin2hex(fread($handle, $bytes));
    fclose($handle);
    return $bytes;
}

Get magic bytes using Java

public static String getMagicBytes(String filePath, int position, int bytes) {
    try {
        byte[] data = Files.readAllBytes(Paths.get(filePath));
        ByteBuffer bb = ByteBuffer.wrap(data);
        bb.position(position);

        StringBuilder sb = new StringBuilder();
        for(int i=0; i<bytes; i++) {
            sb.append(String.format("%02x", bb.get()));
        }
        return sb.toString();
    }catch(IOException ex) {
        ex.printStackTrace();
        return null;
    }
}

Get magic bytes using Python3

def get_magic_bytes(file_path, position=0, nbytes=4):
    try:
        with open(file_path, 'rb') as file:
            file.seek(position)
            magic_bytes = file.read(nbytes)
        return magic_bytes.hex()
    except FileNotFoundError:
        print(f"File {file_path} not found.")
        return None

Get magic bytes using Golang

import (
    "fmt"
    "os"
)

func getMagicBytes(filePath string, position, nbytes int) (string, error) {
    file, err := os.Open(filePath)
    if err != nil {
        return "", err
    }
    defer file.Close()

    bytes := make([]byte, nbytes)
    _, err = file.ReadAt(bytes, int64(position))
    if err != nil {
        return "", err
    }

    return fmt.Sprintf("%x", bytes), nil
}

Get magic bytes using Dart

import 'dart:async';
import 'dart:io';
import 'dart:convert';

Future<String> getMagicBytes(String path, [int position = 0, int nbytes = 4]) async {
  var file = new File(path);
  if (!await file.exists()) {
    print("File does not exist.");
    return null;
  }

  RandomAccessFile openedFile = await file.open(mode: FileMode.read);
  await openedFile.setPosition(position);

  List<int> magicBytes = <int>[];
  for (int i = 0; i < nbytes; i++) {
    magicBytes.add(await openedFile.readByte());
  }

  await openedFile.close();

  return hex.encode(magicBytes);
}