Commands by Cowboy (13)

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Join lines split with backslash at the end
Joins each line that end with backslash (common way to mark line continuation in many languages) with the following one while removing the backslash.

Use result of the last command
\$ which python /usr/bin/python \$ ll `!!` lrwxrwxrwx 1 root root 9 2010-11-08 22:01 /usr/bin/python -> python2.6

Find usb device
I often use it to find recently added ou removed device, or using find in /dev, or anything similar. Just run the command, plug the device, and wait to see him and only him

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"

Run any GUI program remotely
$ ssh -X example.org xeyes The SSH server configuration requires: X11Forwarding yes # this is default in Debian And it's convenient too: Compression delayed

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.."

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"

convert unixtime to human-readable
Mac have direct conversion of seconds (Epoch time)

get all Google ipv4 subnets for a iptables firewall for example
a bit shorter, parenthesis not needed but added for clarity

back ssh from firewalled hosts
host B (you) redirects a modem port (62220) to his local ssh. host A is a remote machine (the ones that issues the ssh cmd). once connected port 5497 is in listening mode on host B. host B just do a ssh 127.0.0.1 -p 5497 -l user and reaches the remote host'ssh. This can be used also for vnc and so on.


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