[plug] pstack

[James Devenish]

In message <20040108122214.GI2065 at amidala>
on Thu, Jan 08, 2004 at 08:22:14PM +0800, Bernard Blackham wrote:
> Why can't you ptrace it?

Did someone mention a can of worms?

 1/ Ptracing is bad :-)
 2/ Process cannot be ptraced (e.g. "operation not permitted").
 3/ Ptracing can interfere with existing parent/child
    relationships at crucial moments (well, at least
    causes some slightly confusing effects).
 4/ Attaching gdb interrupts the process for as long as your gdb session
    is running. I tried `echo backtrace | gdb ...` but it doesn't like
    to do what I was hoping for. (It looks, initially, like the default
    technique is to attach, invoke backtrace, and remain attached while
    scrolling through the bt.)
 5/ Sometimes Linux get weird (see also Craig Ringer's gdm problem).