A CILDB file starts with a 72-byte header, whose layout is as follows:
| Offset | Size | Field | Description |
|---|---|---|---|
| 0 | 16 | Signature | Magic signature for CILDB "_ildb_signature\0" |
| 16 | 16 | GUID | Version GUID |
| 32 | 4 | UserEntryPoint | MethodDef token of the entry point. |
| 36 | 4 | CountOfMethods | Number of rows in the SymMethod table. |
| 40 | 4 | CountOfScopes | Number of rows in the SymScopes table. |
| 44 | 4 | CountOfVars | Number of rows in the SymVariable table. |
| 48 | 4 | CountOfUsing | Number of rows in the SymUsing table. |
| 52 | 4 | CountOfConstants | Number of rows in the SymConstant table. |
| 56 | 4 | CountOfDocuments | Number of rows in the SymDocument table. |
| 60 | 4 | CountOfSequencePoints | Number of rows in the SymSequencePoint table. |
| 64 | 4 | CountOfMiscBytes | Number of bytes in the SymMisc heap. |
| 68 | 4 | CountOfStringBytes | Number of bytes in the SymString heap. |