System Debug Reference Manual (32650-90888)

Chapter 4 121
System Debug Command Specifications :-Exit
DO
This example demonstrates how a simple loop can be used to display the targets for each
STT entry within the current CM segment. Since we know that %31000 is the PCAL
instruction, we simply add the desired STT number and use the DIS command to display
the target entry point name. Control-Y is used to terminate the loop.
Limitations, Restrictions
none
DO
Reexecutes a command from the command stack.
Syntax
DO [ cmd_string ]
DO [
history_index ]
DO, entered alone, reexecutes the most recent command.
Parameters
cmd_string Execute the most recent command in the history stack that commences
with
cmd_string . For example, do wh could be used to match the most
recent WHILE statement.
history_index The history stack index of the command that is to be executed.
A negative index can be used to specify a command relative to the current
command. For example, -2 implies the command used two commands ago.
Examples
%cmdebug > do w
%cmdebug > wl 2+4
%6
Execute the most recent command that started with "w".
Limitations, Restrictions
Upon initial entry into System Debug, the command stack is empty, since no prior
command has been executed. If the DO command is entered as the first command, an empty
command is reexecuted. This is effectively the same as entering a blank line.
The MPE/iX command interpreter allows an edit string to be specified on the DO command
line. This feature is not supported in System Debug.