[PATCH] Use external tool for creating backtraces on crashes if available.

[Alan Coopersmith]

Matthias Hopf wrote:
> This calls /usr/bin/xorg-backtrace to create reasonable commented backtraces
> with gdb. On errors it falls back to the generic method.

There's already similar code in the backtrace.c file in the
# ifdef HAVE_PSTACK case, where we fork the external pstack
process on Solaris to get stack traces that have more information
than the libc builtins allow, like getting full symbol tables from
libelf.

Could we make the fork/exec wrapper common between the two?   I'd
even be okay with making the entire code in backtrace.c common and
just letting the script handle calling gdb or pstack.   (Solaris
systems are more likely to have pstack installed than gdb.)

-- 
	-Alan Coopersmith-        alan.coopersmith at oracle.com
	 Oracle Solaris Platform Engineering: X Window System