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6 WORKING WITH REGISTERS
This section describes the Debugger's internal
process register, and explains how to examine and
modify registers.
It also discusses the use of
register mnemonics, and tells how to proceed from
a new Code Segment and Instruction Pointer (CS:IP)
using CODE-G.
THE PROCESS REGISTER
The process register PR is a Debugger internal
register.
This register always identifies and
keeps track of the current process. The PR is set
automatically to the process identifier of the
process that most recently reached a breakpoint.
For example, if Process 2 is the process that most
recently reached a breakpoint, then PR is set to
2.
When you invoke the Debugger from the Executive or
from the Context Manager (using CODE-GO) just
before the execution of an application system
begins, PR is set to the identifier of the first
user process.
All Debugger commands that involve processes treat
the process with which they are concerned as the
current process. For example, whenever registers
are read or written to, the register of the
current process is used.
EXAMINING AND MODIFYING REGISTERS
To debug a single-process program, you normally do
not need to refer to PR at all. However, to debug
a multiprocess program, you must know which of the
processes involved is the current process.
You
can examine and change PR the same way you would
examine and change any other word location: by
opening it and then entering a new parameter, if
desired.
For example, if the current process is
number 4 and you want to change it to number 7,
type
PR →
Working with Registers
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