$ curl cheat.sh/
 cheat.sheets:dmesg 
# dmesg
# Print or control the kernel ring buffer

# Print the ring buffer contents, then clear it.
dmesg -c

# Display the local time and the delta in human-readable format. Conversion to
# the local time could be inaccurate.
dmesg -e

# Print human-readable timestamps.
dmesg -T

# Human-readable output (color + reltime).
dmesg -H

 tldr:dmesg 
# dmesg
# Write the kernel messages to standard output.
# More information: <https://manned.org/dmesg>.

# Show kernel messages:
dmesg

# Show kernel error messages:
dmesg --level err

# Show kernel messages and keep reading new ones, similar to `tail -f` (available in kernels 3.5.0 and newer):
dmesg -w

# Show how much physical memory is available on this system:
dmesg | grep -i memory

# Show kernel messages 1 page at a time:
dmesg | less

# Show kernel messages with a timestamp (available in kernels 3.5.0 and newer):
dmesg -T

# Show kernel messages in human-readable form (available in kernels 3.5.0 and newer):
dmesg -H

# Colorize output (available in kernels 3.5.0 and newer):
dmesg -L

$
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