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Add all unversioned files to svn
No need for grep, let awk do the match. This will not behave properly if the filenames contains whitespace, which is awk's default field separator.

sort ugly text
Often, when sorting you want the sort to ignore extraneous characters. The b, d, and f tell sort to ignore leading blanks, use 'dictionary order' (ignore punctuation), and ignore (fold) case. Add a "u" if you only want one copy of duplicate lines. This is a great command to use within vim to sort lines of text, using !}sort -bdf

Find the package that installed a command

List the size (in human readable form) of all sub folders from the current location
Sorted in human readable format.

display information about the CPU

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Anti DDOS
Takes IP from web logs and pipes to iptables, use grep to white list IPs.. use if a particular file is getting requested by many different addresses. Sure, its already down pipe and you bandwidth may suffer but that isnt the concern. This one liner saved me from all the traffic hitting the server a second time, reconfigure your system so your system will work like blog-post-1.php or the similar so legitimate users can continue working while the botnet kills itself.

Throttling Bandwidth On A Mac
sudo ipfw pipe 1 config bw 50KByte/s Set the bandwidth (bw) limit to any number you want. For example you could have a 15kb pipe for X application and then a 100kb pipe for another application and attach things to those pipes. If a port isn’t attached to a pipe, it runs at full speed. Change the number (in this case 1) to a different number for a different pipe. The next step is to attach your port. sudo ipfw add 1 pipe 1 src-port 80 In this case anything on port 80 (http) will be set to a limit of 50Kbyte/s. If you want to attach a second port to this pipe, repeat the command but change the port number at the end. src : http://www.mactricksandtips.com/2008/12/throttling-bandwidth-on-a-mac.html

Get the IP address

Fibonacci numbers with awk
Another combination of seq and awk. Not very efficient, but sufficiently quick.


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