Cyc Browser Parameters

This section describes the system parameters that control the behavior and the resource paths for the CYC browser. All of these parameters can be changed at any time after system start-up and take effect immediately, that is, for all following browser requests.

User Preference Settings

Notice that there are additional parameters for gating the CYC browser experience that are under the control of the individual users. These user preferences are stored, on a per-user basis, in the preferences/users/ sub-directory of the CYC installation. This directory must be read and writable by the user who owns the CYC process.
See also the help documentation for the Tools and the Prefs link in the CYC browser tool bar.

 

Access Parameters

These parameters gate what users of the CYC browser have access to. They are configured in the init/parameters.lisp configuration file.

*ALLOW-GUEST-TO-EDIT?*

Either T or NIL. If NIL, then certain browser interactions, including critically modifying the knowledge base, require user authentication. If T, unauthenticated users can modify the knowledge base as well.

*CB-EDITING-ENABLED?*

Either T or NIL. If NIL, then all tools for modifying the knowledge base are not accessible from the browser.

*CB-TOOLBAR-RESTRICT-TO-USER-TOOLS?*

Either T or NIL. If T, then the tools accessible to all users are restricted to those specified in the respective *CB-USER-TOOLBAR-LINKS* value of the users’ preferences. If NIL, the users have access to the Tools menu, and thus to all of the tools available on that server.

Tip: The most straight-forward way to configure the *CB-USER-TOOLBAR-LINKS* value is to do the following:

  1. Set *CB-TOOLBAR-RESTRICT-TO-USER-TOOLS?* to NIL.
  2. Log into the CYC  server as the default user (see *DEFAULT-CYCLIST-NAME* below) for that server.
  3. Using the Tools menu, configure the toolbar to only those tools that the users are supposed to have access to, then click the [Update & Save] button to write out the user preference settings.
  4. Open the user preferences for the default user and copy the two lines that start with *CB-USER-TOOLBAR-LINKS*. to any existing preference files of users whose access needs to be restricted.
  5. Change *CB-TOOLBAR-RESTRICT-TO-USER-TOOLS?* back to T.

*DEFAULT-CYCLIST-NAME*

The name of the constant representing the Cyclist  that is the default Cyclist initially logged into the system, as a string; the recommended setting is “Guest”, especially if guest editing (see above) is disabled.

 

Display Parameters

*PERMIT-UTF-8-CHARACTER-DISPLAY*

Either T or NIL. If T, the CYC browser will correctly display UTF-8 test derived from CYC strings.

 

Resource Location Parameters

These parameters gate where the CYC browser looks for various resources, such as icons or help documentation, that it serves up. All of the values are strings that represent path names; all of the values must be defined.
They are configured in the init/parameters.lisp configuration file. The default values for these parameters refer to the resources as shipped with the standard installation.

 

*HTTP-HTDOCS-DIRECTORY*

This parameter, a string representing a path name, specifies the directory under which documents served by the HTTP server are to be retrieved from. The path can either be relative to the CYC run directory or absolute.
The HTTP server appends the path from the requested URL to this parameter to compute the file system path to the document to serve.
In an installation context, where both an external web-server and the CYC-internal web-server are used--that is, both the HTML and the HTTP service are active; see above--this parameter must be set to the value for the document root of the external web server--for example, the DocumentRoot core directive under Apache 2--if the two services are to give the same browsing experience.

 

*CYC-DOCUMENTATION-URL*

This parameter, a string representing a path, specifies the path from the document root to the Cyc system documentation directory. The path must start and end with a slash (/).

 

*HTML-IMAGE-DIRECTORY*

This parameter, a string representing a path, specifies the path from the document root to the directory where the images (.png, .gif, .jpg etc) for the CYC browser are stored. The path must start and end with a slash (/).

 

*HTML-JAVASCRIPT-DIRECTORY*

This parameter, a string representing a path, specifies the path from the document root to the
directory under which Javascript files used by the browser are stored. The path must start and end with a slash (/).

 

*HTML-CSS-DIRECTORY*

This parameter, a string representing a path, specifies the path from the document root to the
directory under which CSS (Cascading Style Sheet)  files used by the browser are stored
The path must start and end with a slash (/).