CRT
application/octet-stream
Magic Bytes
Offset: 0
43 36 34 20 43 41 52 54 52 49 44 47 45 20 20 20
The Commodore 64 Cartridge (CRT) format is a container structure originally developed by the VICE emulator team to preserve data from physical hardware cartridges. This legacy format allows modern software emulators and specialized hardware flash devices to replicate the original functionality of read-only memory expansion boards. Primarily used for long-term software preservation and retro-computing, these files pose minimal security risks as they operate within isolated virtual hardware environments.
Validation Code
How to validate .crt files in Python
Python
def is_crt(file_path: str) -> bool:
"""Check if file is a valid CRT by magic bytes."""
signature = bytes([0x43, 0x36, 0x34, 0x20, 0x43, 0x41, 0x52, 0x54, 0x52, 0x49, 0x44, 0x47, 0x45, 0x20, 0x20, 0x20])
with open(file_path, "rb") as f:
return f.read(16) == signatureHow to validate .crt files in Node.js
Node.js
function isCRT(buffer: Buffer): boolean {
const signature = Buffer.from([0x43, 0x36, 0x34, 0x20, 0x43, 0x41, 0x52, 0x54, 0x52, 0x49, 0x44, 0x47, 0x45, 0x20, 0x20, 0x20]);
return buffer.subarray(0, 16).equals(signature);
}
Go
func IsCRT(data []byte) bool {
signature := []byte{0x43, 0x36, 0x34, 0x20, 0x43, 0x41, 0x52, 0x54, 0x52, 0x49, 0x44, 0x47, 0x45, 0x20, 0x20, 0x20}
if len(data) < 16 {
return false
}
return bytes.Equal(data[:16], signature)
}API Endpoint
GET
/api/v1/crt
curl https://filesignature.org/api/v1/crt