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An alias to re-run last command with sudo. Similar to "sudo !!"
I didn't come up with this myself, but I always add this to my .bash_aliases file. It's essentially the same idea as running "sudo !!" except it's much easier to type. (You can't just alias "sudo !!", it doesn't really work for reasons I don't understand.) "fc" is a shell built-in for editing and re-running previous commands. The -l flag tells it to display the line rather than edit it, and the -n command tells it to omit the line number. -1 tells it to print the previous line. For more detail: $help fc

Update IP filter for qBittorrent
Downloads Bluetack's level 1 IP blocklist in .p2p format, suitable for various Bittorrent clients.

list files recursively by size

Check if a string is into a variable
Returns true (0) if the string is into $var, or false (1) if not.

socat TCP-LISTEN:5500 EXEC:'ssh user@remotehost "socat STDIO UNIX-CONNECT:/var/run/mysqld/mysqld.sock"'
Listens on local port 5500 and connects to remotehost with username user to tunnel the given socket file. Will work with anything, but can be useful if there's a need for a local application to connect with a remote server which was started without networking.

Remove the first character of each line in a file

Get your external IP address
Request all information about my IP address in json format

Cut/Copy everything arround brackets or parentheses on vim (in normal mode)
Put the cursor on either curly braces ( {, } ). Then press d% The d is delete command, and % is movement command that move the cursor to another matching parentheses (or curly braces in this case). This action will delete every character that was on the way of the movement (from the first curly braces to the second).

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" }

SMTP Analysis
This works just as well for SMTP. You could run this on your mail server to watch e-mail senders and recipients: tcpdump -l -s0 -w - tcp dst port 25 | strings | grep -i 'MAIL FROM\|RCPT TO'


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