Command Level

A command level is an input stream for the DCL level interpreter. The terminal is considered command level 0 (often called the DCL or the interactive command level), an interactive command procedure executes at command level 1, and a command procedure called by the interactive command procedure executes at command level 2. The maximum command level you can achieve by nesting command procedures is 16, including the top-level command procedure.

Every command level has its own local symbol table which is inherited by the next command levels. All command levels share the global symbol table.

The STOP command returns control to command level 0, regardless of the current command level. The EXIT command returns control to the next higher command level.