2 VDE, UTILITIES, OpenVMS Source Code Control System  B The VDE tools allow you to maintain and to control a large number  of CMS libraries.   ? Full documentation of VDE is available in Postscript, HTML, and  Bookreader format.  C VDE requires the presence of various software tools, including CMS  A and Oracle Rdb.  Complete details are in the installation manual.   A PLMENU is a set of procedures layered on VDE and CMS that provide ? various functions.  A subset of PLMENU tools are included here. 