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Find files and calculate size of result in shell
Find files and calculate size with stat of result in shell

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

Check your unread Gmail from the command line
Just an alternative with more advanced formating for readability purpose. It now uses colors (too much for me but it's a kind of proof-of-concept), and adjust columns.

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

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" }

Use socat to emulate an SMTP mail SERVER
Lots of scripts show you how to use socat to send an email to an SMTP server; this command actually emulates an SMTP server! It assumes the client is only sending to one recipient, and it's not at all smart, but it'll capture the email into a log file and the client will stop retrying. I used this to diagnose what emails were being sent by cron and subsequently discarded, but you can use it for all sorts of things.

Get MX records for a domain
command is shorter, output unnecessary longer

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

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

sort the contents of a text file in place.
sorts the contents of a file without the need for a second file to take the sorted output. This was previously entered as `sort -g list.txt -o $_` but as others have pointed out the $_ references the previous command. so this would've worked had that been the second part of a command joined with && like: cat list.txt && sort -g list.txt -o $_ The user below me Robin had the most correct command.


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