Commands by alesplin (2)

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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" }

Quickly re-execute a recent command in bash
! will expand to the last time you ran , options and all. It's a nicer alternative to ^R for simple cases, and it's quite helpful for those long commands you run every now and then and haven't made aliases or functions for. It's similar to command 3966, in some sense.

Determine what version of bind is running on a dns server.
Due to the recent dynamic update vulnerability with bind, I was forced to dig a little deeper into dig...

Downsample mp3s to 128K
This will lower the quality of mp3 files, but is necessary to play them on some mobile devices.

pop-up messages on a remote computer
Run this command when you are physically at the computer you wish to send pop-up messages to. Then when you ssh in to it, you can do this: echo "guess who?" > commander guess who? will then pop up on the screen for a few moments, then disappear. You will need to create the commander file first. I mess with my wife all the time with this. i.e. echo "You have given the computer a virus. Computer will be rendered useless in 10 seconds." > commander lol

List files with full path
Prints contents of current directory with the full path prepended to each entry. You can add '-type f' if you don't want the directories to show up (for those less familiar with find). I can't believe ls doesn't have an option for this.

A random password generator

FizzBuzz in one line of Bash
The (in)famous "FizzBuzz" programming challenge, answered in a single line of Bash code. The "|column" part at the end merely formats the output a bit, so if "column" is not installed on your machine you can simply omit that part. Without "|column", the solution only uses 75 characters. The version below is expanded to multiple lines, with comments added. for i in {1..100} # Use i to loop from "1" to "100", inclusive. do ((i % 3)) && # If i is not divisible by 3... x= || # ...blank out x (yes, "x= " does that). Otherwise,... x=Fizz # ...set x to the string "Fizz". ((i % 5)) || # If i is not divisible by 5, skip (there's no "&&")... x+=Buzz # ...Otherwise, append (not set) the string "Buzz" to x. echo ${x:-$i} # Print x unless it is blanked out. Otherwise, print i. done | column # Wrap output into columns (not part of the test).

Search some text from all files inside a directory

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


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