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

reset Mageia urpmi media sources to network only
On Mageia (and Mandriva) Linux, this command will clear your existing urpmi configuration and configure it to use only network sources. It can be useful after you have installed from CD/DVD and don't want to continually be prompted to insert CD/DVD each time you install a package. acknowledgement: blino

Calculate the mean or average of a single column of numbers in a text file
single-column-numbers.txt is a text file with 22658 rows (numbers) in a single column. Each number can range from 0 to 134298679.533591 and the dot is for the decimals. This is done with perl because awk can't sum such high numbers.

Truncate long strings in columns and use custom header names
Using the --table-truncate ( -T ) option, you can specify the columns you will allow to be truncated. This helps when you have some columns that are unusually long, or a small terminal window. In this example we will print out the /etc/passwd file in columns. We are using a colon as our separator ( -s: ), defining that we want table output ( -t ), defining the column names ( -N ) and allowing the column NAME to be truncated ( -T ).

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

website recursive offline mirror with wget
website recursive offline mirror with wget

External IP (raw data)

Protect directory from an overzealous rm -rf *
Forces the -i flag on the rm command when using a wildcard delete.

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.

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"


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