Tornado

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Debugger
Displaying Summary Thread Information
The command info threads shows what thread ID corresponds to which VxWorks
task. For example, immediately after executing attach system to stop a VxWorks
target, the info threads display resembles the following:
(gdb) info threads
4 task 0x4fc868 tExcTask 0x444f58 in ?? ()
3 task 0x4f9f40 tLogTask 0x444f58 in ?? ()
2 task 0x4c7380 + tNetTask 0x4151e0 in ?? ()
1 task 0x4b0a24 tWdbTask 0x4184fe in ?? ()
(gdb)
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In the info threads output, the left-most number on each line is the debugger’s
thread ID. The single asterisk at the left margin indicates which thread is the
current thread. The current thread identifies the “most local” perspective: debugger
commands that report task-specific information, such as bt and info regs (as well
as the corresponding displays) apply only to the current thread.
The next two columns in the thread list show the VxWorks task ID and the task
name; if the system context is shown, the single word system replaces both of these
columns. The thread (either a task, or the system context) currently scheduled by
the kernel is marked with a + to the right of the task identification.
! CAUTION: The thread ID of the system thread is not constant. To identify the
system thread at each suspension, you must use info threads whenever the
debugger regains control, in order to see whether the system thread is present and,
if so, what its ID is currently.
The remainder of each line in the info threads output shows a summary of each
thread’s current stack frame: the program counter value, and the corresponding
function name.
The thread ID is required to specify a particular thread with commands such as
break and thread.
Switching Threads Explicitly
To switch to a different thread (making that thread the current one for debugging,
but without affecting kernel task scheduling), use the thread command. For
example:
(gdb) thread 2
[Switching to task 0x3a4bd8 tShell ]
#0 0x66454 in semBTake ()
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