CPIO (.cpio)
.cpio file signature | application/x-cpio
cpioASCII archive file with crc
Magic Bytes
Offset 0
30 37 30 37 30 37
Sources: Apache Tika, Wikipedia
All Known Signatures
3 signature variants are documented for .cpio files across multiple sources.
| Hex Signature | Offset | Sources |
|---|---|---|
| 30 37 30 37 30 37 | 0 | Apache Tika, Wikipedia |
| 30 37 30 37 30 31 | 0 | Apache Tika, Wikipedia |
| 30 37 30 37 30 32 | 0 | Apache Tika, Wikipedia |
Extension
.cpio
MIME Type
application/x-cpio
Byte Offset
0
Risk Level
Safe
Validation Code
How to validate .cpio files in Python
def is_cpio(file_path: str) -> bool:
"""Check if file is a valid CPIO by magic bytes."""
signature = bytes([0x30, 0x37, 0x30, 0x37, 0x30, 0x37])
with open(file_path, "rb") as f:
return f.read(6) == signatureHow to validate .cpio files in Node.js
function isCPIO(buffer: Buffer): boolean {
const signature = Buffer.from([0x30, 0x37, 0x30, 0x37, 0x30, 0x37]);
return buffer.subarray(0, 6).equals(signature);
}How to validate .cpio files in Go
func IsCPIO(data []byte) bool {
signature := []byte{0x30, 0x37, 0x30, 0x37, 0x30, 0x37}
if len(data) < 6 {
return false
}
return bytes.Equal(data[:6], signature)
}API Endpoint
/api/v1/cpio
curl https://filesignature.org/api/v1/cpio
See the full API documentation for all endpoints and parameters.
Frequently Asked Questions
What is a .cpio file?
A .cpio file is a CPIO file. cpioASCII archive file with crc
What are the magic bytes for .cpio files?
The magic bytes for CPIO files are 30 37 30 37 30 37 at byte offset 0. These bytes uniquely identify the file format regardless of the file extension.
How do I validate a .cpio file?
To validate a .cpio file, read the first bytes of the file and compare them against the known magic bytes (30 37 30 37 30 37) at offset 0. This is more reliable than checking the file extension alone, as extensions can be renamed.
What is the MIME type for .cpio files?
The primary MIME type for .cpio files is application/x-cpio.
Is it safe to open .cpio files?
CPIO (.cpio) files are generally safe to open. They are classified as low risk because they primarily contain data rather than executable code. However, always ensure files come from a trusted source.