The shibd command runs the Shibboleth SP daemon process that handles state management and most of the SAML and security processing of the software. On Windows, it is designed to run either from the command line or as a "service". The process backgrounds itself by default, but can be kept in the foreground with a command line option.
The following command line options are available based on the platform.
Runs in console mode and loads the configuration, logging any serious issues to the console, then exits.
Runs the program as a console application in the foreground rather than as a service.