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Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Take a file as input (two columns data format) and sum values on the 2nd column for all lines that have the same value in 1st column
Example: $ cat

Find the package that installed a command

Search apache virtual host by pattern
Outputs contents of virtual hosts containing PATTERN. Particularly useful for pefrorming complex searches. E.g. search for docroot of www.example.com: $ sed -n '/^[^#]*

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

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

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

Add thousand separator with sed, in a file or within pipe
Does not necessarily require a file to process, it can be used in a pipe as well: $ cat filename | sed -e :a -e 's/\(.*[0-9]\)\([0-9]\{3\}\)/\1,\2/;ta' I don't remember where I copy/pasted this from, I wish I credited the original author

Auto Get Missing Launchpad Keys
You can choose these mirror servers to get gpg keys, if the official one ever goes offline keyserver.ubuntu.com pool.sks-keyservers.net subkeys.pgp.net pgp.mit.edu keys.nayr.net keys.gnupg.net wwwkeys.en.pgp.net #(replace with your country code fr, en, de,etc)

Test I/O performance by timing the writing of 100Mb to disk
Write 200 blocks of 512k to a dummy file with dd, timing the result. The is useful as a quick test to compare the performance of different file systems.


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