kgdb |
[-a | -f |
-fullname ] [-b
rate] [-q |
-quiet ] [-v ]
[-w ] [-d
crashdir] [-c
core | -n
dumpnr | -r
device] [kernel
[core]] |
The kgdb
utility is a debugger based on
gdb(1) that
allows debugging of kernel core files.
The options are as follows:
-a
- Increase the annotation level. An annotation level of 1 features the
historical
-fullname
option of
gdb(1).
This is useful when running kgdb
in Emacs. The
-f
or -fullname
options
are supported for backward compatibility as well.
-b
rate
- Set the baudrate to rate.
-q
- Suppress printing of the banner when the debugger starts. The
-quiet
form is supported for compatibility as
well.
-v
- Increase verbosity.
-w
- Opens kmem-based targets in read-write mode. (This is identical to what
--wcore
used to do in previous gdb versions for
FreeBSD.)
-d
crashdir
- Use crashdir instead of the default,
/var/crash to locate kernel core dump files in.
The name vmcore. plus the dump number will be
appended to determine the actual dump file name.
-c
core
- Explicitly use core as the core dump file.
-n
dumpnr
- Use the kernel core dump file numbered dumpnr for
debugging.
-r
device
- Use device to connect
kgdb
to for a remote debugging session.
The -c
, -n
, and
-r
options are mutually exclusive.
Optionally, the name of the kernel symbol file and the name of the
core dump file can be supplied on the command-line as positional arguments.
If no kernel symbol file name has been given, the symbol file of the
currently running kernel will be used. If no core dump file has been
specified through either of the options or the last command-line argument,
/dev/mem will be opened to allow debugging the
currently running kernel.
- /dev/mem
- Default memory image to open if no core dump file has been specified.
- /var/crash
- Default directory to locate kernel core dump files.
The kgdb
utility first appeared in its current form in
FreeBSD 5.3.