下列常量由此扩展定义，且仅在此扩展编译入 PHP 或在运行时动态载入时可用。
| Constant | Value | Description |
|---|---|---|
GOPHER_DOCUMENT |
0 | Standard text/plain document. |
GOPHER_DIRECTORY |
1 | A resource containing a gopher formatted directory listing. |
GOPHER_BINHEX |
4 | A BinHex encoded binary file. |
GOPHER_DOSBINARY |
5 | A DOS formatted binary archive. |
GOPHER_UUENCODED |
6 | A UUEncoded file. |
GOPHER_BINARY |
9 | A generic binary file. |
GOPHER_INFO |
255 | An Informational entry |
GOPHER_HTTP |
254 | A reference to an HTTP resource. |
GOPHER_UNKNOWN |
-1 | An unrecognized entry. |