ports/161578: strace is not working

[Dietmar Schmidt]

>Number:         161578
>Category:       ports
>Synopsis:       strace is not working
>Confidential:   no
>Severity:       non-critical
>Priority:       high
>Responsible:    freebsd-ports-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Fri Oct 14 08:30:11 UTC 2011
>Closed-Date:
>Last-Modified:
>Originator:     Dietmar Schmidt
>Release:        8.2, 9.0-BETA3
>Organization:
>Environment:
FreeBSD X.X.X 8.2-RELEASE FreeBSD 8.2-RELEASE #0: Fri Feb 18 02:24:46 UTC 2011     root at almeida.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC  i386
>Description:
strace is not working in newer FreeBSD versions.
In 8.0 FreeBSD works as expected.
in 8.2 and 9.0-BETA3 strace does not work. Not sure for 8.1, sorry.

The output of strace is "pread: Device busy" for every syscall?
and  
"PIOCRUN: Input/output error
trouble opening proc file"
at the end of the strace output.

I know about truss and ktrace, but we use strace for compatibility with other unixes/linux.

>How-To-Repeat:
strace ps
strace ls
>Fix:
The error occurs in syscall.c line 1300
if (pread(tcp->pfd_reg, &regs, sizeof(regs), 0) < 0) {

unsure how to fix it.

>Release-Note:
>Audit-Trail:
>Unformatted: