Windows Help index file (.gid)
.gid file signature | application/octet-stream
Magic Bytes
Offset: 0
3F 5F 03 00
Windows Help index file
Sources: Gary Kessler
All Known Signatures
2 signature variants are documented for .gid files across multiple sources.
| Hex Signature | Offset | Sources |
|---|---|---|
| 3F 5F 03 00 | 0 | Gary Kessler |
| 4C 4E 02 00 | 0 | Gary Kessler |
Validation Code
How to validate .gid files in Python
def is_gid(file_path: str) -> bool:
"""Check if file is a valid GID by magic bytes."""
signature = bytes([0x3F, 0x5F, 0x03, 0x00])
with open(file_path, "rb") as f:
return f.read(4) == signatureHow to validate .gid files in Node.js
function isGID(buffer: Buffer): boolean {
const signature = Buffer.from([0x3F, 0x5F, 0x03, 0x00]);
return buffer.subarray(0, 4).equals(signature);
}How to validate .gid files in Go
func IsGID(data []byte) bool {
signature := []byte{0x3F, 0x5F, 0x03, 0x00}
if len(data) < 4 {
return false
}
return bytes.Equal(data[:4], signature)
}API Endpoint
/api/v1/gid
curl https://filesignature.org/api/v1/gid
See the full API documentation for all endpoints and parameters.
Frequently Asked Questions
What is a .gid file?
A .gid file is a Windows Help index file file. Windows Help index file
What are the magic bytes for .gid files?
The magic bytes for Windows Help index file files are 3F 5F 03 00 at byte offset 0. These bytes uniquely identify the file format regardless of the file extension.
How do I validate a .gid file?
To validate a .gid file, read the first bytes of the file and compare them against the known magic bytes (3F 5F 03 00) at offset 0. This is more reliable than checking the file extension alone, as extensions can be renamed.
What is the MIME type for .gid files?
There is no officially registered MIME type for .gid files. Systems typically use application/octet-stream as a generic fallback when handling this format.
Is it safe to open .gid files?
Windows Help index file (.gid) 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.