System Debug Reference Manual (32650-90888)

92 Chapter4

System Debug Command Speciﬁcations :-Exit

• While on the ICS.

• While disabled.

• In a "dying" process. (See the DYING_DEBUG variable in the ENV command discussion.)

• In a job. (See the JOB_DEBUG variable in the ENV command discussion.)

Breakpoints set in CM translated code (which has been optimized) may not always be hit.

In some cases, the optimizer saves an instruction by targeting a branch to the delay slot

immediately following a node point. As a result, a breakpoint that was set at the node

point is not hit.

CAUTION

Setting global breakpoints must be done with extreme care, and only when

debugging requires it. Do not try this on a system under use. A global

breakpoint may cause processes to suspend unexpectedly.

Debug only

Breakpoint delete. Deletes a breakpoint entry speciﬁed by index number.

Syntax

BD [

number

| @ [:

| @] ]

The BD command is used to delete process-local breakpoints and global (system-wide)

breakpoints. Only users with privileged mode (PM) capability are allowed to view and

delete global breakpoints. Users without PM capability may only specify PINs that are

descendant processes (any generation) of the current PIN.

When an NM breakpoint set in translated code is deleted, all corresponding CM

breakpoints are automatically removed. When a CM breakpoint is deleted, the CM

reference counter in the corresponding NM breakpoint (if any) is decremented. If the

reference count reaches zero, the NM breakpoint is deleted. Refer to appendix C for a

discussion of CM object code translation, node points, and breakpoints in translated CM

code.

Parameters

number

| @ The index number of the breakpoint entry that is to be deleted. The

character "@" can be used to delete all breakpoint entries.

If the index number is omitted, Debug displays each breakpoint, one at a

time, and asks the user if it should be deleted (Y/N?). The following

responses are recognized:

Y[E[S]] Yes, remove the breakpoint.