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Find artist and title of a music cd, UPC code given (first result only)
I like curl better than wget, I just think that curl -s is a lot simpler than wget ... see I forget what you even have to do to get wget to pipe it's output Anyway, all in one sed command as "requested"

Find dead symbolic links
-L tells find to follow symbolic links, so -type l will only return links it can't follow (i.e., those that are broken).

Check to make sure the whois nameservers match the nameserver records from the nameservers themselves
Change the $domain variable to whichever domain you wish to query. Works with the majority of whois info; for some that won't, you may have to compromise: domain=google.com; for a in $(whois $domain | grep "Domain servers in listed order:" --after 3 | grep -v "Domain servers in listed order:"); do echo ">>> Nameservers for $domain from $a

set your ssd disk as a non-rotating medium
if you still get a permissions error using sudo, then nano the file: sudo nano -w /sys/block/sdb/queue/rotational and change 1 to 0 this thread: http://www.ocztechnologyforum.com/forum/showpost.php?p=369836&postcount=15 says that this will "help the block layer to optimize a few decisions"

list files recursively by size

print first n characters of any file in human readble form using hexdump
Usefull to determine unknown file type

Carriage return for reprinting on the same line
The above code is just an example of printing on the same line, hit Ctrl + C to stop When using echo -ne "something\r", echo will: - print "something" - dont print a new line (-n) - interpret \r as carriage return, going back to the start of the line (-e) Remember to print some white spaces after the output if your command will print lines of different sizes, mainly if one line will be smaller than the previous Edit from reading comments: You can achieve the same effect using printf (more standardized than echo): while true; do printf "%-80s\r" "$(date)"; sleep 1; done

rsync directory tree including only files that match a certain find result.
'-mtime -10' syncs only files newer 10 days (-mtime is just one example, use whatever find expressions you need) printf %P: File's name with the name of the command line argument under which it was found removed. this way, you can use any src directory, no need to cd into your src directory first. using \\0 in printf and a corresponding --from0 in rsync ensures that even filenames with newline characters work (thanks syssyphus for #3808). both, #1481 and #3808 just work if you either copy the current directory (.) , or the filesystem root (/), otherwise the output from find and the source dir from rsync just don't match. #7685 works with an arbitrary source directory.

check open ports without netstat or lsof

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


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