Module Name:	src
Committed By:	atatat
Date:		Thu May 15 13:18:19 UTC 2003

Modified Files:
	src/share/man/man4: ddb.4
	src/sys/ddb: db_command.c db_xxx.c

Log Message:
(1) Don't print the message buffer (via ddb's dmesg command) if the
message buffer has not yet been set up, mimicking code from the top of
the sysctl routine for retrieving the message buffer.

(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.

(3) Documentation for the above.


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.