|  |  | 
				| DOC_LIBRARY | Extracts documentation headers from IDL programs. | 
				| HELP | Provides information about the current IDL session. | 
				| MEMORY | Returns information about dynamic memory currently in use by the IDL session. | 
				| MK_HTML_HELP | Converts text documentation headers to HTML files. | 
				| ONLINE_HELP | Invokes online help viewer from programs. | 
				| STRUCT_HIDE | Prevents the IDL HELP procedure from displaying information about structures or objects. |