> The NetSD proc(4) (AKA procfs) is fairly old and don't understand LWP at
>>all.  ttrace(2) from HP-UX might be a better interface for GDB but proc(4)
>>can be useful because you don't need a program to glance at things.  It
>>also seems (to me) that it'd be easier to adapter to LWPs (and get GDB
>>support) than implmenting ttrace(2) from stratch.
> 
> 
> that might be true, but it would move in the direction of solaris and
> linux where, if a certain pseudo-filesystem isn't mounted, lots of
> stuff just doesn't work.

GDB is a tart.  It will try to work with what ever is available.  If it 
doesn't, then it's a bug.

More seriously, /proc is likely better long-term, it makes available a 
lot more information than ttrace can.  Know about `(gdb) gcore' which is 
can be implemented using /proc?

Andrew