''This article refers the mainframe text editor. For the IEEE technical society, see Computer-Aided Design Technical Committee. CANDE (Command AND Edit) is a command line shell and text editor on the MCP (Master Control Program) operating system which runs on the Unisys Clearpath series of mainframes. Originally implemented on Burroughs large systems, it has a range of features for interacting with the operating system execution environment, focused on executing, editing and compiling programs, and creating, copying, moving, renaming, and deleting files in general. Its full name is CANDE MCS. MCS, or Message Control Subsystem is the general form of a systems program in the Burroughs architecture (other than MCP, the Master Control Program or core OS). As an MCS, CANDE is more than just an editor as it provides overall control for a network of users. The editing capabilities of CANDE are anachronistic for casual (as opposed to scripted) editing as they predate full screen and graphical editors. CANDE was also used on the Burroughs CMS (mini computer) range, with very similar syntax. In contemporary MCP, CANDE is primarily used thru the ODT (Operator Display Terminal) and MARC (Menu Assisted Resource Control) on emulators of the original character oriented terminals as with other legacy mainframe interfaces such as ISPF. Features CANDE provides a command-line interpreter and line editor, although unlike the modern interpretation of an operating system command line interpreter, the CANDE commands are compiled into the CANDE MCS, as shell like capabilities are provided by WFL. Other notable features and functions include: Create, edit, and maintain (copy, move, remove, print, rename) data and program files Compile and execute programs Access and display information about the data communication network including terminal communication lines and remote devices Dynamically alter the communication network Access and display job and task information Utility functions (calculator, system utility test, etc.) In addition to these features CANDE has an on-line help facility. Implementation For extra speed, CANDE implemented user context switching by swapping a block at the top of the stack. This novel method broke several assumptions built into the design of Burroughs large systems, in particular the handling of virtual memory descriptors, and meant that CANDE itself had to be written in DCALGOL with system-level privileges. Architecturally, CANDE is split into two main sections: a primary, single-instanced main process originally supporting up to 255 simultaneous users, and one or more worker stacks. The main process