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Combine two mp3's or more into 1 long mp3
This just combines multiple mp3's into one mp3 file. Basically it is a easy join for mp3's

Erase CD RW

Batch File Rename with awk and sed

Size(k) of directories(Biggest first)
somewhat faster version to see the size of our directories. Size will be in Kilo Bytes. to view smallest first change '-k1nr' to '-k1n'.

find text in a file
this will find text in the directory you specify and give you line where it appears.

shush MOTD
I'm annoyed by the boilerplate "don't login unless you are supposed messages in our environment" - this shuts them up.

1:1 copy of a volume
copies all files from the source disk / (skipping boundaries of mouted -in volumes) to /mnt/mydisk. Logical links are being preserved as well as devices, pipes etc. This can copy a MacOS X or Linux volume and keep it bootable. Note: its not suited to copy files with MacOS 9 style resources.

Read and write to TCP or UDP sockets with common bash tools
Ever needed to test firewalls but didn't have netcat, telnet or even FTP? Enter /dev/tcp, your new best friend. /dev/tcp/(hostname)/(port) is a bash builtin that bash can use to open connections to TCP and UDP ports. This one-liner opens a connection on a port to a server and lets you read and write to it from the terminal. How it works: First, exec sets up a redirect for /dev/tcp/$server/$port to file descriptor 5. Then, as per some excellent feedback from @flatcap, we launch a redirect from file descriptor 5 to STDOUT and send that to the background (which is what causes the PID to be printed when the commands are run), and then redirect STDIN to file descriptor 5 with the second cat. Finally, when the second cat dies (the connection is closed), we clean up the file descriptor with 'exec 5>&-'. It can be used to test FTP, HTTP, NTP, or can connect to netcat listening on a port (makes for a simple chat client!) Replace /tcp/ with /udp/ to use UDP instead.

Get Nyan'd
Get nyan'd

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.


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