AR
application/x-archive
Magic Bytes
Offset: 0
3D 3C 61 72 3E
The AR format is a legacy archive utility originally developed for the Unix operating system and currently maintained as part of the GNU Binutils suite. It is primarily used by developers to create static libraries for linking object files and serves as the internal container format for Debian software packages. While largely replaced by more modern formats like TAR for general purposes, it remains a critical component of standard C compilation toolchains across POSIX-compliant systems.
Validation Code
How to validate .ar files in Python
Python
def is_ar(file_path: str) -> bool:
"""Check if file is a valid AR by magic bytes."""
signature = bytes([0x3D, 0x3C, 0x61, 0x72, 0x3E])
with open(file_path, "rb") as f:
return f.read(5) == signatureHow to validate .ar files in Node.js
Node.js
function isAR(buffer: Buffer): boolean {
const signature = Buffer.from([0x3D, 0x3C, 0x61, 0x72, 0x3E]);
return buffer.subarray(0, 5).equals(signature);
}
Go
func IsAR(data []byte) bool {
signature := []byte{0x3D, 0x3C, 0x61, 0x72, 0x3E}
if len(data) < 5 {
return false
}
return bytes.Equal(data[:5], signature)
}API Endpoint
GET
/api/v1/ar
curl https://filesignature.org/api/v1/ar