Generic file access in Houdini is provided by the FS_Reader, FS_Writer, and FS_Info classes. In addition to generic stream file access, these classes also support an extensible mechanism for reading and writing data through a file helper plugin architecture. When reading or writing to a given file path string, the helpers are first queried to see if any of them support a file path matching a particular protocol: prefix. If the file path matches the appropriate prefix, then the helper will be used instead of treating the path as a disk file.

The default helper's provided by Houdini for FS_Reader and FS_Info are:

Web Server
This helper supports paths that using the http: protocol.
Operator Type Library (OTL) sections
This helper supports paths that refer to sections embedded in an operator type library (OTL) or operator definition (HDA). It uses the oplib: and opdef: protocols.

See Also: Reading Files, Writing Files, File Information, Add Custom Helper