Andrew Brown <atatat@netbsd.org> wrote on Thu, 15 May 2003
at 13:18:19 +0000 in <20030515131819.9BCFFB004@cvs.netbsd.org>:


> (2) Add a /l modifier to the trace command.  This makes it print the
> backtrace using printf() instead of db_printf(), which has the nice
> side-effect of also putting it into the message buffer.  A kernel with
> ddb in it but disabled (ie, ddb.onpanic set to zero) will print a
> backtrace (which ends up in the message buffer) before dumping (or
> not, depending on the value of kern.dump_on_panic) and rebooting, but
> if ddb is not disabled, the backtrace is not printed, and there's no
> way to get it to display a backtrace such that you can retrieve it
> after the dump.  The backtrace printed by gdb is sometimes a little
> different.

I don't think there's any reason why this support should be specific
to "trace". It was my intent (for some time, sigh) to add a "diary"
command to ddb, which, when toggled on, would cause all ddb output
would go to the message buffer.

I still think that's right, and that when that goes in, this should
come out. Do you object?

--jhawk

> To generate a diff of this commit:
> cvs rdiff -r1.64 -r1.65 src/share/man/man4/ddb.4
> cvs rdiff -r1.69 -r1.70 src/sys/ddb/db_command.c
> cvs rdiff -r1.21 -r1.22 src/sys/ddb/db_xxx.c
> 
> Please note that diffs are not public domain; they are subject to the
> copyright notices on the relevant files.