Commands by Jubal (2)

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Faster find and move using the find and xargs commands. Almost as fast as locate.
Only tested on Linux Ubunty Hardy. Works when file names have spaces. The "-maxdepth 2" limits the find search to the current directory and the next one deeper in this example. This was faster on my system because find was searching every directory before the current directory without the -maxdepth option. Almost as fast as locate when used as above. Must use double quotes around pattern to handle spaces in file names. -print0 is used in combination with xargs -0. Those are zeros not "O"s. For xargs, -I is used to replace the following "{}" with the incoming file-list items from find. Echo just prints to the command line what is happening with mv. mv needs "{}" again so it knows what you are moving from. Then end with the move destination. Some other versions may only require one "{}" in the move command and not after the -I, however this is what worked for me on Ubuntu 8.04. Some like to use -type f in the find command to limit the type.

Do command when logged in from certain ips using ssh
Place in ~/.bashrc If you login to a ssh server from different ips, sometimes you want to do something specific for each. e.g., quickly go into screen -x session from a phone, but not your desktop.

Print all lines between two line numbers
This command uses awk(1) to print all lines between two known line numbers in a file. Useful for seeing output in a log file, where the line numbers are known. The above command will print all lines between, and including, lines 3 and 6.

Convert Squid unixtime logs in human-readable ones
On-the-fly conversion of Unix Time to human-readable in Squid's access.log

Get your external IP address ( 10 characters long )
Shortest url to a external IP-service, 10 characters.

convert filenames in current directory to lowercase
The simplest way I know.

Get the IP address of a machine. Just the IP, no junk.
Why use many different utilities all piped together, when you only need two?

list files recursively by size

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"

Quickly create an alias for changing into the current directory
Put the function in your .bashrc and use "map [alias]" to create the alias you want. Just be careful to not override an existing alias.

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