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Expand shortened URLs
curl(1) is more portable than wget(1) across Unices, so here is an alternative doing the same thing with greater portability. This shell function uses curl(1) to show what site a shortened URL is pointing to, even if there are many nested shortened URLs. This is a great way to test whether or not the shortened URL is sending you to a malicious site, or somewhere nasty that you don't want to visit. The sample output is from: $ expandurl http://t.co/LDWqmtDM

Display 16 largest installed RPMs in size order, largest first
Interesting to see which packages are larger than the kernel package. Useful to understand which RPMs might be candidates to remove if drive space is restricted.

get the ascii number with bash builtin printf

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 all installed kernels on Ubuntu except current one
Lists all installed kernels minus the current one. This is useful to uninstall older kernels that take too much space on /boot partition.

Syntax Highlight your Perl code

Check if a domain is available and get the answer in just one line
Returns nothing if the domain exists and 'No match for domain.com' otherwise.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

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"

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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