Commands by ankush108 (20)

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Show running services (using systemctl)

Record camera's output to a avi file
video.avi is the resulting file. Press Ctrl+c to stop the recording. You can change the OVC option to another to record into a different format.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Do a search-and-replace in a file after making a backup

pretend to be busy in office to enjoy a cup of coffee
just make some data scrolling off the terminal. wow.

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Convert the contents of a directory listing into a colon-separated environment variable
Useful for making a CLASSPATH out of a list of JAR files, for example. Also: export CLASSPATH=.:$(find ./lib -name '*.jar' -printf '%p:')

shows history of logins on the server
outputs a history of logins on the server (top 10, when piped to 'head'); optional flags: '-a' put the hostname at the end of the line (good for long hostnames), '-i' post the IP instead of the hostname, '-F' put the full login and logout times, rather than short times.

list block devices
Shows all block devices in a tree with descruptions of what they are.

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested


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