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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"

Highlight network TX, RX information change

Create a random file of a certain, and display progress along the way.
SIZE is the number of gigabytes and the file name is at the end. Random data is generated by encrypting /dev/zero, similar to other techniques posted on here.

Decode a MIME message
will decode a mime message. usefull when you receive some email and file attachment that cant be read.

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"

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.

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Create backup copy of file, adding suffix of the date of the file modification (NOT today's date)
When I go to change a configuration file I always like to make a backup first. You can use "cp -p" to preserve the modification time, but it gets confusing to have file.prev, file.prev2, etc. So I like to add a YYMMDD suffix that shows when the file was last changed. "stat -c %Y" gives you the modification time in epoch seconds, then "date -d @" converts that to whatever format you specify in your "+format" string.

checks size of directory & delete it if its to small
only simple example how to combine rclone & jq

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


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