Commands by edshadi (1)

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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"

Find files with lines that do not match a pattern
This one would be much faster, as it's only one executed command.

Remove empty directories
You can also use, $ find . -depth -type d -exec rmdir {} \; 2>/dev/null

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

Generate random valid mac addresses
Python Alternative

Getting a domain from url, ex: very nice to get url from squid access.log

Apply, in parallel, a bc expression to CSV
Define a function that applies bc, the *nix calculator, with the specified expression to all rows of the input CSV. The first column is mapped to {1}, second one to {2}, and so forth. See sample output for an example. This function uses all available cores thanks to GNU Parallel. Requires GNU Parallel

Check if running in an X session
If you want to display a dialog (using xdialog/kdialog/zenity) you need to make sure that you have a valid X session. Checks for the existence of the DISPLAY variable.

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"

Recursive replace of directory and file names in the current directory.
no grep, no perl, no pipe. even better in zsh/bash4: $ for i in **/*oldname*; do "mv $i ${i/oldname/newname/}"; done No find, no grep, no perl, no pipe


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