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Create a bunch of dummy text files

grep tab chars
mixing tabs and spaces for indentation in python would confuse the python interpreter, to avoid that, check if the file has any tab based indentation. "^V" => denotes press control + v and press tab within quotes. $ cat improper_indent.py class Tux(object): print "Hello world.." $ grep " " improper_indent.py print "Hello world.."

show all programs connected or listening on a network port
Use the aliased command 'nsl'

Start a SOCKS proxy to avoid a restrictive firewall
You may go to Internet by means of your home ssh server. You must configure your local proxy to send traffic through the proxy. Many programs allows that: firefox, pidgin, skype, gnome, etc. Your home ssh server must listen in any of the ports permitted by your enterprise firewall. That usually includes 80 and 443.

Install pip with Proxy
Installs pip packages defining a proxy

Customize time format of 'ls -l'
the --time-style argument to 'ls' takes several possible modifiers: full-iso, long-iso, iso, locale, +FORMAT. The +FORMAT modifier uses the same syntax as date +FORMAT. --time-style=+"%Y-%m-%d %H:%M:%S" strikes a happy medium between accuracy and verbosity: $ ls -lart --time-style=long-iso doesn't show time down to the nearest second, $ ls -lart --time-style=full-iso displays time to 10E-9 second resolution, but with no significant digits past the full seconds, also showing the timezone: $ -rw-r--r-- 1 bchittenden bchittenden 0 2011-02-10 12:07:55.000000000 -0500 bar

Start a new command in a new screen window
If you are already running screen then you often want to start a command in a fresh window. You use this alias by typing 's whatever' from your command line and 'whatever' starts running in a new window. Good with interactive commands like info, vim, and nethack.

Convert JSON to YAML
You need to install the Catmandu Perl module via `cpanm Catmandu`

Mount a VMware virtual disk (.vmdk) file on a Linux box
This does not require you to know the partition offset, kpartx will find all partitions in the image and create loopback devices for them automatically. This works for all types of images (dd of hard drives, img, etc) not just vmkd. You can also activate LVM volumes in the image by running $vgchange -a y and then you can mount the LV inside the image. To unmount the image, umount the partition/LV, deactivate the VG for the image $vgchange -a n then run $kpartx -dv to remove the partition mappings.

Set file access control lists
The file myfile is owned by tom and has read and write permissions for tom. Group and other permissions are empty which make myfile readable and writable only by tom. setfacl enables user tom to give read permission to user john only. The command 'ls -l' shows a '+' sign telling us that file access control list has been setup for myfile.


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