The following table lists the library procedure return values and their explanations.
| 1 - 99 | Standard library error values. |
| 109-199 | Reserved for future use. |
| PIP-ERROR | procedure failed; use SPERRGET to get details. |
| PIP-ERROR-ARGUMENT | Invalid arguments to procedure. |
| PIP-ERROR-INVALID-HANDLE | Invalid handle returned from SPINIT. |
| PIP-ERROR-BAD-FILE | File has incorrect signature. |
| PIP-ERROR-EXPIRED | File is out of date. |
| PIP-ERROR-LICENSE | License file is missing, Spatial+ not licensed, or bad password. |
| PIP-ERROR-LIMIT | Internal table overflow. |
| PIP-ERROR-MEMORY | Insufficient memory. |
| PIP-ERROR-NOT-FOUND | File not found. |
| PIP-ERROR-UNCLASSED | Unclassed error. |
| PIP-ERROR-UNKNOWN | Unknown error. |
| PIP-IN-BORDER | The point is inside the polygon, and the associated buffer. This can only occur for a polygon, and not line or point feature. |
| PIP-IN-BUFFER | A buffer area, but not a polygon, was found that contained the point. |
| PIP-IN-POLYGON | A polygon was found that contained the point. |
| PIP-INPUT-IN-OBJECT | Input region is inside the object file region object. |
| PIP-NO-REGION-OVERLAP | Regions do not overlap. |
| PIP-NOT-FOUND | Object not found. |
| PIP-OBJECT-EQUALS-INPUT | The object file region equals the input region. |
| PIP-OBJECT-EQUALS-OUTPUT | The object file region equals the output region. |
| PIP-OBJECT-IN-INPUT | Object file region object is inside the input region. |
| PIP-OK | procedure successful. |
| PIP-READ-STORED | Object was read and stored. |
| PIP-READ-WRONG-TYPE | Object was not a point, line, or polygon and was not stored. |
| PIP-REGION-A-EQUALS-B | The regions are identical. |
| PIP-REGION-A-IN-B | Region A is wholly encompassed by Region B. |
| PIP-REGION-B-IN-A | Region B is wholly encompassed by Region A. |
| PIP-REGION-OVERLAP | The two regions overlap but the intersection area does not equal either region. |