Commands by Xeno (2)

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sum numbers in the file (or stdin)
add integers from the stdin and print out the result usually, cat /tmp/file | echo $(($(tr '\n' '+')0))

is today the end of the month?

Find the package that installed a command

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Install a basic FreeBSD system
Install a basic FreeBSD system on a distant server. I use this to install FreeBSD on servers that can only boot a Linux rescue system. This sytem loads on ram when booted, so it is possible to install freely. You can even install on ZFS root !

validate the syntax of a perl-compatible regular expression
Place the regular expression you want to validate between the forward slashes in the eval block.

Bingo-like raffle
Random choose numbers from 1 to 100 with 5 seconds interval without duplicates.

Which fonts are installed?
See all fonts installed in your system

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" }

clear MyDNS-ng cache
Occasionally, to force zone updating, cache flush is necessary. This command is better than restart the mydns daemon.


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