Windows Help file
application/octet-stream
Magic Bytes
Offset: 0
3F 5F
Windows Help (WinHelp) is a proprietary documentation format developed by Microsoft for earlier versions of the Windows operating system. It stores hyperlinked text, images, and index data, serving as the standard help system for software applications prior to the introduction of HTML Help. Considered an obsolete format, it is no longer supported natively on modern Windows platforms, having been superseded by Compiled HTML (CHM) files to improve functionality and security.
Validation Code
How to validate .hlp files in Python
Python
def is_hlp(file_path: str) -> bool:
"""Check if file is a valid HLP by magic bytes."""
signature = bytes([0x3F, 0x5F])
with open(file_path, "rb") as f:
return f.read(2) == signatureHow to validate .hlp files in Node.js
Node.js
function isHLP(buffer: Buffer): boolean {
const signature = Buffer.from([0x3F, 0x5F]);
return buffer.subarray(0, 2).equals(signature);
}
Go
func IsHLP(data []byte) bool {
signature := []byte{0x3F, 0x5F}
if len(data) < 2 {
return false
}
return bytes.Equal(data[:2], signature)
}API Endpoint
GET
/api/v1/hlp
curl https://filesignature.org/api/v1/hlp