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Join lines split with backslash at the end
Joins each line that end with backslash (common way to mark line continuation in many languages) with the following one while removing the backslash.

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.

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" }

Listing package man page, services, config files and related rpm of a file, in one alias
Many times I give the same commands in loop to find informations about a file. I use this as an alias to summarize that informations in a single command. Now with variables! :D

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

Show a config file without comments

A DESTRUCTIVE command to render a drive unbootable
THIS COMMAND IS DESTRUCTIVE. That said, lets assume you want to render your boot drive unbootable and reboot your machine. Maybe you want it to boot off the network and kickstart from a boot server for a fresh OS install. Replace /dev/fd0 with the device name of your boot drive and this DESTRUCTIVE command will render your drive unbootable. Your BIOS boot priority should be set to boot from HD first, then LAN.

Execute a command on logout
Execute a command on shell logout,and run it until is finished,then shell is closed.

Create a single-use TCP (or UDP) proxy
Redirect the local port 2000 to the remote port 3000. The same but UDP: $ nc -u -l -p 2000 -c "nc -u example.org 3000" It may be used to "convert" TCP client to UDP server (or viceversa): $ nc -l -p 2000 -c "nc -u example.org 3000"

Create a large test file (taking no space).


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