On Monday 24 July 2006 08:10, Robert Watson wrote: > On Mon, 24 Jul 2006, Greg 'groggy' Lehey wrote: > > > On Friday, 21 July 2006 at 13:29:38 +0200, Dag-Erling Smrgrav wrote: > >> Tom Rhodes <[EMAIL PROTECTED]> writes: > >>> Wait. I'm lost. Isn't truss(1) broken on FreeBSD? > >> > >> Depends on your definition of broken. It kind of works provided you have > >> /proc mounted. Still, there's really not much point in using it; ktrace(1) > >> is better in almost all respects. > > > > truss is good in that it gives immediate output. I used it recently under > > 6.1, and I somehow missed that it was broken. > > A few things are wrong with truss, none that make it completely broken: > > (1) In the past there were a number of reports of problems with race > conditions during truss attach/detach. These reports have entirely > disappeared, as far as I can tell, due to process locking fixes, procfs > fixes, debugging fixes, etc. If they still exist, they should be > investigated, but up-to-date debugging infomation will be needed.
I think the PHOLD/P_WEXIT stuff in 6.1 might have fixed these. > (2) truss relies on procfs, which is known to be evil, and as such, doesn't > work out of the box since we don't mount procfs out of the box. Several > people have worked on enhancing ptrace() so that it can be used to > implement truss, but no one has finished this work. I think the necessary > ptrace() traps now exist for system calls so that this could be done. Well, the biggest thing I found when doing the PHOLD/P_WEXIT stuff that was missing was PIOCWAIT and PIOCCONT (IIRC). Specifically, we don't currently have any ptrace() equivalent to that. -- John Baldwin _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/cvs-all To unsubscribe, send any mail to "[EMAIL PROTECTED]"
