Re: [PATCH] Fix strace -T

[Jon TURNEY]

On 08/09/2011 20:09, Christopher Faylor wrote:
On Thu, Sep 08, 2011 at 07:37:29PM +0100, Jon TURNEY wrote:

strace -T to toggle stracing of a process doesn't seem to work at the moment.
Attached is a patch to make it work again.

2011-09-08  Jon TURNEY<jon.tur...@dronecode.org.uk>

        * include/sys/strace.h (strace): Add toggle() method
        * strace.cc (toggle): Implement toggle() method
        * sigproc.cc (wait_sig): Use strace.toggle() in __SIGSTRACE

IIRC, the intent was for hello() to toggle (in which case I guess it
should be hellogoodbye).  Why do you even need this functionality?
I'd just as soon remove it.

I found it very helpful to have this working when I was looking at a problem 
which occurred when running the twisted testsuite ([1], I think), as running 
the entire testsuite with strace enabled greatly slowed it down and generated 
a vast amount of output, and the problem did not reproduce when running a 
single test.  Being able to disable strace output until close to the point of 
failure was useful.

I didn't want to touch strace::hello() as it's called from a few other places 
than __SIGSTRACE processing, and I don't understand them well enough to know 
if toggling in those places is correct.

[1] http://cygwin.com/ml/cygwin/2011-03/msg00437.html