In a message dated 9/27/2006 2:54:13 A.M. Eastern Standard Time,  
is@netbsd.org writes:
On Tue, Sep 26, 2006 at 03:41:58PM -0400,  SigmFSK@aol.com wrote:
> Hi all:
> Is there a way to track the  program counter of a user program as  it 
changes 
> when running an  executable?

gdb ?

-is
 
-------
 
thanks for the tip.  I've been trying ways to get the info via  gdb.
 
The executable in question is a.out-sunos-big format, statically  linked.
It runs on a sun3/80 under NetBSD 3.0, NetBSD 1.5.3, and SunOS  4.1.1.
 
With NetBSD 3.0, I can either run it directly, or run it  all-the-way-through 
under gdb.  But I can't single step through it, or have  it stop at any 
breakpoints in gdb.  I can set breakpoints which show up  correctly with "info 
break", but upon "run"ning, it just runs all the way  through.  If I control-c in 
the middle, it stops and shows me the actual  program counter, and the 
dissassemble command shows the correct  instructions.  But if I "si" single machine 
instruction step - it runs all  the way to the end.  Must be something with the 
executable is not the  default elf format.
 
If I run it under gdb on NetBSD 1.5.3 (last version for default elf  format), 
or Sunos 4.1.1, upon "run"ning, gdb complains that it can't access  memory 
location 0x4 and quits.
 
It seems overkill to use an in-circuit-emulator for something so apparently  
simple, but I'm starting to run out of  ideas.
/arthur