| -C |
Clear the ring buffer.
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| -c |
Clear the ring buffer after first printing its contents.
|
| -D |
Disable the printing of messages to the console.
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| -d |
Display the timestamp and the time delta spent between messages.
If used together with --notime then only the time delta without the timestamp is printed.
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| -E |
Enable printing messages to the console.
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| -e |
Display the local time and the delta in human-readable format.
Be aware that conversion to the local time could be inaccurate (see -T for more details).
|
| -F FILE |
Read the syslog messages from the given FILE. Note that -F does not support messages in kmsg format. See -K instead.
|
| -f LIST |
Restrict output to the given (comma-separated) LIST of facilities.
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| -H |
Enable human-readable output. See also --color, --reltime and --nopager.
|
| -J |
Use JSON output format. The time output format is in "sec.usec" format only,
log priority level is not decoded by default (use --decode to split into facility and priority),
the other options to control the output format or time format are silently ignored.
|
| -K FILE |
Read the /dev/kmsg messages from the given FILE. Different record as expected to be separated by a NULL byte.
|
| -k |
Print kernel messages.
|
| -L |
Colorize the output. The optional argument when can be auto,
never or always. If the when argument is omitted, it defaults to auto.
The colors can be disabled; for the current built-in default see the --help output. See also the COLORS section below.
|
| -l LIST |
Restrict output to the given (comma-separated) LIST of levels.
|
| -n LEVEL |
Set the LEVEL at which printing of messages is done to the console.
|
| -P |
Do not pipe output into a pager. A pager is enabled by default for --human output.
|
| -p |
Add facility, level or timestamp information to each line of a multi-line message.
|
| -r |
Print the raw message buffer, i.e., do not strip the log-level prefixes, but all unprintable characters are still escaped (see also --noescape).
|
| -S |
Force dmesg to use the syslog(2) kernel interface to readkernel messages. The default is to use /dev/kmsg rather than syslog(2) since kernel 3.5.0.
|
| -s SIZE |
Use a buffer of SIZE to query the kernel ring buffer. This is 16392 by default. (The default kernel syslog buffer size was 4096 at first, 8192 since 1.3.54, 16384 since 2.1.113.)
|
| -T |
Print human-readable timestamps.
|
| --since TIME |
Display record since the specified TIME. Supported is the subsecond granularity.
|
| --until TIME |
Display record until the specified TIME. Supported is the subsecond granularity.
|
| -t |
Do not print kernel’s timestamps.
|
| -u |
Print userspace messages.
|
| -w |
Wait for new messages. This feature is supported only on systems with a readable /dev/kmsg (since kernel 3.5.0).
|
| -W |
Wait and print only new messages.
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| -x |
Decode facility and level (priority) numbers to human-readable prefixes.
|
| -h |
Display help text and exit.
|
| -V |
Print version and exit.
|