Re: follow-on{fork|clone}

[Tom Tromey <tromey at redhat dot com>]

Phil> Given that you turn off follow-on-fork sometimes (in GDB) is
Phil> that mechanic useful for Frysk as well? Why do you turn it off?
Phil> Is it because of bugs, or more of a focus?

In gdb it is off by default.  Or, more precisely, gdb just has one
setting -- follow the parent or follow the child -- and it defaults to
follow the parent.

At least on FC-6, with the distro gdb, it is also buggy.  I don't
think I've had it work successfully.

With CVS gdb it seems a bit better.

So, it is a combo: partly bugs but partly because usually I want to
follow the parent.  This latter thing is a false dichotomy, my hope
for frysk is that I won't have to choose.

Phil> In writing watchpoints I personally cannot see why
Phil> follow-on-{fork|clone} would ever be turned off

One might imagine the debugger using too much memory as it attaches to
and loads debug info for every application in a big hierarchy of
fork/execs.  (I have no idea how fhpd scales here.)  In a situation
like this you'd want to be able to control things more tightly.

For the kind of debugging I'm doing right now, yeah, I would like to
simply watch all the processes started from "gcc" and have fhpd show
me when any of them crashes.  That would be delightful and is really
not possible with gdb today.

Tom