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Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)
Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.

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

Install Linux Kernel Headers on Debian-based systems
Install the Linux kernel headers for currently running kernel version on Debian-based systems via apt-get

Log the current memory statistics frequently to syslog
Uses logger in a while loop to log memory statistics frequently into the local syslog server.

count IPv4 connections per IP
usefull in case of abuser/DoS attacks.

Change the console keyboard layout

How many days until the end of the year

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

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" }

List open IPv4 connections


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