Commands by happycat (2)

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Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

tail: watch a filelog
-f file(s) to be monitorized -n number of last line to be printed on the screen in this example, the content of two files are displayed

Print text string vertically, one character per line.
Define a function $ vert () { echo $1 | grep -o '.'; } Use it to print some column headers $ paste

Cut/Copy brackets or parentheses on vim (in normal mode)
We have for example : func () { echo FOO echo BAR } Place the cursor under a bracket and press d + %. It will cut everything inside and the brackets. It let : func () You can copy text with y + %

Consolle based network interface monitor
ethstatus part of ethstatus package, is a consolle based monitor for network interfaces. Nicely display on screen a real time summary about bandwidth, speed and packets.

List all NPM global packages installed

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

reverse order of file

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

Display a block of text: multi-line grep with perl
-n reads input, line by line, in a loop sending to $_ Equivalent to while () { mycode } -e execute the following quoted string (i.e. do the following on the same line as the perl command) the elipses .. operator behaves like a range, remembering the state from line to line.

Stay in the loop…

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