SWI-Prolog offers the possibility to log the interaction with the user on a file.107A similar facility was added to Edinburgh C-Prolog by Wouter Jansweijer. All Prolog interaction, including warnings and tracer output, are written to the protocol file.
- Start protocolling on file File. If there is already a protocol file open, then close it first. If File exists it is truncated.
- Equivalent to protocol/1, but does not truncate the File if it exists.
- Stop making a protocol of the user interaction. Pending output is flushed on the file.
- True if a protocol was started with protocol/1 or protocola/1 and unifies File with the current protocol output file.