Portable Pixmap

import magic
# Libmagic natively detects PPM files and correctly identifies them based on the P3/P6 signature
print(magic.from_file('render.ppm', mime=True)) # Outputs 'image/x-portable-pixmap'

const fs = require('fs');
// Manually checking the PPM magic bytes (P3 or P6)
const buffer = Buffer.alloc(2);
const fd = fs.openSync('render.ppm', 'r');
fs.readSync(fd, buffer, 0, 2, 0);
fs.closeSync(fd);
const isPPM = buffer[0] === 0x50 && (buffer[1] === 0x33 || buffer[1] === 0x36);
console.log('Is Portable Pixmap (PPM):', isPPM);

import (
    "bytes"
    "net/http"
)
// Native Go HTTP detection does not recognize PPM natively.
// Check directly for the P3 or P6 signatures:
// isPPM := len(buf) >= 2 && buf[0] == 'P' && (buf[1] == '3' || buf[1] == '6')

$mime = mime_content_type('render.ppm');
echo $mime; // Standard PHP setups typically return 'image/x-portable-pixmap'