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give a binary the ability to open ports below 1024 as non root user
Binding a server to privileged port on Linux w/o running as root This is applicable to any service using privileged ports (< 1024), for instance to run a HTTP server on port 80 or a LDAP directory server on port 389 for example.

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"

Create a large test file (taking no space).

Go up multiple levels of directories quickly and easily.
This is a kind of wrapper around the shell builtin cd that allows a person to quickly go up several directories. Instead of typing: cd ../.. A user can type: cd ... Instead of: cd ../../.. Type: cd .... Add another period and it goes up four levels. Adding more periods will take you up more levels.

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

list files recursively by size

Resize photos without changing exif
To resize photos without changing exif datas, pretty cool for gps tagging. (Require ImageMagick)

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"

Group OR'd commands where you expect only one to work
Something to stuff in an alias when you are working in multiple environments. The double-pipe OR will fall through until one of the commands succeeds, and the rest won't be executed. Any STDERR will fall out, but the STDOUT from the correct command will bubble out of the parenthesis to the less command, or some other command you specify.

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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