Technical data

System Dump Analyzer
SHOW STACK
SDA provides the following information in each stack display.
Section Contents
Identity of stack SDA indicates whether the stack is a process stack
(user, supervisor, executive, or kernel) or the processor
interrupt stack. If the interrupt stack is being displayed,
SDA displays the CPU ID of the processor that owns
it. Similarly, if the SDA current process is currently
scheduled on a processor in the system, SHOW STACK
also specifies the CPU ID of the processor on which the
process is scheduled.
Stack pointer The stack pointer identifies the top of the stack. The
display indicates the stack pointer by the symbol SP =>.
Stack address SDA lists all the virtual addresses that the operating
system has allocated to the stack. The stack addresses
are listed in a column that increases in increments of 4
bytes (one longword).
Stack contents SDA lists the contents of the stack in a column to the
right of the stack addresses.
Symbols SDA attempts to display the contents of a location
symbolically, using a symbol and an offset.
If the address is not within FFF
16
of the value of any
existing symbol, this column is left blank.
If a stack is empty, the display shows the following:
SP => (STACK IS EMPTY)
Example
SDA> SHOW STACK
Process stacks (on CPU 00)
--------------------------
Current operating stack (USER):
7FF73278 200C0000
7FF7327C 00001518 SGN$C_MAXPGFL+518
7FF73280 7FF732F0
7FF73284 000187A7 RMS$_ECHO+72E
SP => 7FF73288 0000060A BUG$_NOHDJMT+002
7FF7328C 00000000
7FF73290 00000003
7FF73294 7FF73800
7FF73298 7FF73800
The SHOW STACK command displays a user stack that was the current
operating stack for a process scheduled on CPU 00. The data shown above the
stack pointer might not be valid. The symbol to the right of the columns, BUG$_
NOHDJMT+002, is the result of the SDA attempt to interpret the contents of the
longword at the top of the stack as a symbol meaningful to the user. In this case,
the value on the stack and the value of BUG$_NOHDJMT are unrelated.
SDA–177