Commands by Escher (14)

What's this? is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

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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"

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Prints line numbers
If you don't have nl on your system, this achieves a similar effect, the default behavior in nl is to not number blank lines, but this does.

list files recursively by size

Convert camelCase to underscores (camel_case)
Useful for switching over someone else's coding style who uses camelCase notation to your style using all lowercase with underscores.

Do Google search from that command line opening into a new Firefox tab.
Usage: google "[search string]" Example: google "something im searching for" This will launch firefox and execute a google search in a new tab with the provided search string. You must provide the path to your Firefox binary if using cygwin to $ff or create an alias like follows: alias firefox='/cygdrive/c/Program Files (x86)/Mozilla Firefox/firefox.exe' Most Linux flavors with Firefox installed will use just ff="firefox" and even OSX.

Check the status of a network interface

shell function to underline a given string.
underline() will print $1, followed by a series of '=' characters the width of $1. An optional second argument can be used to replace '=' with a given character. This function is useful for breaking lots of data emitted in a for loop into sections which are easier to parse visually. Let's say that 'xxxx' is a very common pattern occurring in a group of CSV files. You could run $ grep xxxx *.csv This would print the name of each csv file before each matching line, but the output would be hard to parse visually. $ for i in *.csv; do printf "\n"; underline $i; grep "xxxx" $i; done Will break the output into sections separated by the name of the file, underlined.

Notepad in a browser
A commandline version of the notepad in a browser: All credit to the origional author of this fantastic command, whos only failing as most of the comments pointed out was that it wasn't a command... well, now its a command. Send all upvotes to dtlp747.

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"

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