MDB provides facilities for controlling and tracing the execution of live running programs, including both user applications and the live operating system kernel and device drivers. You can use the mdb command to control user processes that are already running, or create new processes under the control of the debugger. You can boot or load kmdb to control the execution of the operating system kernel itself, or debug a device driver. This chapter describes the built-in dcmds that can be used to control target execution. These commands can be used in either mdb or kmdb, except as noted in the descriptions. Additional topics relating only to execution control in kmdb are discussed in Kernel Execution Control Using kmdb.