Amiga DiskMasher compressed archive

application/octet-stream

Safe

Magic Bytes

Offset: 10
23 20 54 68 69 73 20 69 73 20 61 20 73 68 65 6C 6C 20 61 72 63 68 69 76 65

The Amiga DiskMasher System (DMS) is a legacy disk imaging and compression format originally developed by Simple Design Solutions for the Commodore Amiga computing platform. It was primarily utilized to compress entire floppy disks into single files for efficient storage and distribution across early telecommunications networks like bulletin board systems. While now obsolete, the format remains a standard in the retro-computing community for software preservation and loading disk images into modern system emulators.

Extension

.dms

MIME Type

application/octet-stream

Byte Offset

10

Risk Level

Safe

Validation Code

How to validate .dms files in Python

Python
def is_dms(file_path: str) -> bool:
    """
    Check if file is a valid DMS by magic bytes.
    Signature offset: 10 bytes
    """
    signature = bytes([0x23, 0x20, 0x54, 0x68, 0x69, 0x73, 0x20, 0x69, 0x73, 0x20, 0x61, 0x20, 0x73, 0x68, 0x65, 0x6C, 0x6C, 0x20, 0x61, 0x72, 0x63, 0x68, 0x69, 0x76, 0x65])
    with open(file_path, "rb") as f:
        f.seek(10)
        return f.read(25) == signature

How to validate .dms files in Node.js

Node.js
function isDMS(buffer: Buffer): boolean {
  // Signature offset: 10 bytes
  const signature = Buffer.from([0x23, 0x20, 0x54, 0x68, 0x69, 0x73, 0x20, 0x69, 0x73, 0x20, 0x61, 0x20, 0x73, 0x68, 0x65, 0x6C, 0x6C, 0x20, 0x61, 0x72, 0x63, 0x68, 0x69, 0x76, 0x65]);
  if (buffer.length < 35) return false;
  return buffer.subarray(10, 35).equals(signature);
}
Go
func IsDMS(data []byte) bool {
    // Signature offset: 10 bytes
    signature := []byte{0x23, 0x20, 0x54, 0x68, 0x69, 0x73, 0x20, 0x69, 0x73, 0x20, 0x61, 0x20, 0x73, 0x68, 0x65, 0x6C, 0x6C, 0x20, 0x61, 0x72, 0x63, 0x68, 0x69, 0x76, 0x65}
    if len(data) < 35 {
        return false
    }
    return bytes.Equal(data[10:35], signature)
}

API Endpoint

GET /api/v1/dms
curl https://filesignature.org/api/v1/dms

Related Formats