Netscape Communicator
application/octet-stream
Magic Bytes
Offset: 0
00 20 AF 30
The Netscape Communicator Summary (SNM) format was created by Netscape Communications Corporation as an indexing system for its legacy email and newsgroup client. It stores message metadata and folder offsets, enabling the software to quickly retrieve and display email headers without processing the larger underlying mailbox files. This obsolete binary format is generally safe, though it is no longer supported by modern applications following the discontinuation of the Netscape software suite.
Validation Code
How to validate .snm files in Python
Python
def is_snm(file_path: str) -> bool:
"""Check if file is a valid SNM by magic bytes."""
signature = bytes([0x00, 0x20, 0xAF, 0x30])
with open(file_path, "rb") as f:
return f.read(4) == signatureHow to validate .snm files in Node.js
Node.js
function isSNM(buffer: Buffer): boolean {
const signature = Buffer.from([0x00, 0x20, 0xAF, 0x30]);
return buffer.subarray(0, 4).equals(signature);
}
Go
func IsSNM(data []byte) bool {
signature := []byte{0x00, 0x20, 0xAF, 0x30}
if len(data) < 4 {
return false
}
return bytes.Equal(data[:4], signature)
}API Endpoint
GET
/api/v1/snm
curl https://filesignature.org/api/v1/snm