kdump — display
kernel trace data
kdump |
[-dHlnRTXx] [-f
file] [-m
maxdata] [-P
program] [-p
pid] [-t
trstr] [-u
label] |
kdump displays the kernel trace files
produced with ktrace(1) in
human-readable format. By default, the file
ktrace.out in the current directory is displayed,
unless overridden by the -f option.
The options are as follows:
-d
- Display all numbers in decimal. By default, values are printed out in
hexadecimal.
-f
file
- Display the specified file instead of ktrace.out.
Specifying ‘-’ will read from standard input.
-H
- Display thread identifiers.
-l
- Loop reading the trace file, once the end-of-file is reached, waiting for
more data.
-m
maxdata
- Display at most maxdata bytes when decoding
I/O.
-n
- Suppress ad hoc translations. Normally
kdump tries
to decode many system calls into a more human-readable format. For
example, ioctl(2) values are
replaced with the macro name and errno values are
replaced with the strerror(3)
string. Suppressing this feature yields a more consistent output format
and is easily amenable to further processing.
-P
program
- Show output only for processes with program as their
command name.
-p
pid
- Show output only for the pid specified.
-R
- Display relative timestamps (time since previous entry).
-T
- Display absolute timestamps for each entry (seconds since the Epoch).
-TR
- If both options are specified, display timestamps relative to trace
start.
-t
trstr
- Select which tracepoints to display. The argument can contain one or more
of the following letters. By default all trace points except for
X are enabled.
c
- trace system calls
i
- trace I/O
n
- trace namei translations
p
- trace violation of
pledge(2) restrictions
s
- trace signal processing
S
- trace violation of
pinsyscalls(2)
t
- trace various structures
u
- trace user data coming from
utrace(2)
x
- trace argument vector in
execve(2)
X
- trace environment in
execve(2)
+
- trace the default points
-u
label
- Display utrace(2) tracepoints
having utrace(2) label
label as strings with
vis(3) escaping, without
ktrace(2) header
information.
-X
- Display I/O data with hexadecimal data and printable ASCII characters side
by side.
-x
- Display I/O data in hexadecimal.
The -t and -u
options are mutually exclusive; the last one specified overrides any
previous ones.
- ktrace.out
- default ktrace dump file
The kdump command appeared in
4.3BSD-Reno.