Commands by Vagrant (1)

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shutdown if wget exit

Run a command when a file is changed

extract column from csv file
extracts the 5th column using the delimiter ','

Spoof your wireless MAC address on OS X to 00:e2:e3:e4:e5:e6
If you want to check that the spoof worked, type the same command as earlier: $ifconfig en1 | grep ether Now you will see: $ether 00:e2:e3:e4:e5:e6 For the wired ethernet port: $sudo ifconfig en0 ether 00:e2:e3:e4:e5:e6

Counts number of lines (in source code excluding comments)
I took java to make the find command simpler and to state that it works for any language supported by cpp. cpp is the C/C++ preprocessor (interprets macros, removes comments, inserts includes, resolves trigraphs). The -fpreprocessor option tells cpp to assume the input has already been preprocessed so it will only replace comment lines with blank lines. The -L 1 option tells xargs to launch one process for each line, indeed cpp can only process one file at the time...

Find the package that installed a command

Get your external IP address
curl ifconfig.me/ip -> IP Adress curl ifconfig.me/host -> Remote Host curl ifconfig.me/ua ->User Agent curl ifconfig.me/port -> Port thonks to http://ifconfig.me/

find files containing text
I find this format easier to read if your going through lots of files. This way you can open the file in any editor and easily review the file

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"

How many files in the current directory ?
A simple "ls" lists files *and* directories. So we need to "find" the files (type 'f') only. As "find" is recursive by default we must restrict it to the current directory by adding a maximum depth of "1". If you should be using the "zsh" then you can use the dot (.) as a globbing qualifier to denote plain files: zsh> ls *(.) | wc -l for more info see the zsh's manual on expansion and substitution - "man zshexpn".

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