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The program listening on port 8080 through IPv6
Gets the application's name that's listening from the port 8080 through IPv6

The simplest way to transport information over a network
Einstein's razor: As simple as possible, but not simpler. On the destination machine netcat listens on any port (1234 in the example) and sends anything it receives into a file or pipe. On the source machine a separate netcat takes input from a file or pipe and sends it over the network to the listener. This is great between machines on a LAN where you don't care about authentication, encryption, or compression and I would recommend it for being simpler than anything else in this situation. Over the internet you should use something with better security.

find files containing text
-l outputs only the file names -i ignores the case -r descends into subdirectories

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"

Mac OS-X-> copy and paste things to and from the clipboard from the shell
Copies whatever is piped to the pbcopy command to the clipboard. pbpaste ... well pastes whats on the clipboard.

convert filenames in current directory to lowercase

Merge several pdf files into a single file

Double your disk read performance in a single command
(WARN) This will absolutely not work on all systems, unless you're running large, high speed, hardware RAID arrays. For example, systems using Dell PERC 5/i SAS/SATA arrays. If you have a hardware RAID array, try it. It certainly wont hurt. You may be can test the speed disk with some large file in your system, before and after using this: $ time dd if=/tmp/disk.iso of=/dev/null bs=256k To know the value of block device parameter known as readahead. $ blockdev --getra /dev/sdb And set the a value 1024, 2048, 4096, 8192, and maybe 16384... it really depends on the number of hard disks, their speed, your RAID controller, etc. (see sample)

Find the 20 biggest directories on the current filesystem
This command will tell you the 20 biggest directories starting from your working directory and skips directories on other filesystems. Useful for resolving disk space issues.

Watch Star Wars via telnet
Use Ctrl-] to stop it.


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