Re: Tracepoints documentation

[Michael Snyder <msnyder@cygnus.com>]

Eli Zaretskii wrote:
> 
> On Wed, 21 Mar 2001, Elena Zannoni wrote:
> 
> > I retireved from my dusty mailbox some tracepoint documentation that
> > was written some time back (when the tracepoints were originally
> > implemented) (1998, that is).  I reformatted it from a .doc file. This
> > should be suitable for inclusion in the gdb user's manual.
> 
> Thanks!
> 
> > The texinfo/info formatting is not very well done. I'll leave that to
> > you. :-)
> 
> Will do.
> 
> > Hope it is useful. Unfortunately there isn't a remote target that
> > supports tracepoints at the moment, so we cannot verify that all works
> > as claimed.
> 
> Understood.
> 
> I still have one aspect of tracepoints that I couldn't figure out,
> though.  The original paper about tracepoints (presented by Jim and
> Michael during some conference, I think) mentions a program called
> ``Introspect'' which serves as the remote agent for tracepoints.  Is
> it indeed needed, and if so, where is its source?

"Introspect" is sort of a code name for the tracing functionality of GDB.
However, you do need a special target "stub" (a gdbserver or something like it)
that knows how to perform the tracing stuff, since most of the tracing work
is done on the target side.

We (the old Cygnus) had one customer who implemented their own target-side
tracing server.  We also wrote a sort-of reference implementation ourselves,
but it has never been released.

I hope someday to get the introspect code merged into libremote (Red Hat's
portable gdbserver-like library).  Meanwhile, there is nothing preventing
people from writing an introspect target.  The paper and the documentation
that Elena's given you, plus the documentation of the remote protocol, 
are a fairly complete spec.