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Runs previous command replacing foo by bar every time that foo appears
Very useful for rerunning a long command changing some arguments globally. As opposed to ^foo^bar, which only replaces the first occurrence of foo, this one changes every occurrence.

Password Generation
Produces secure passwords that satisfy most rules for secure passwords and can be customized for correct output as needed. See "man pwgen" for details.

Discovering all open files/dirs underneath a directory
It may be helpful in case you need to umount a directory and some process is preventing you to do so keeping the folder busy. The lsof may process the +D option slowly and may require a significant amount of memory because it will descend the full dir tree. On the other hand it will neither follow symlinks nor other file systems.

Changes standard mysql client output to 'less'.
Changes standard mysql client output to 'less'. In another words makes query results of mysql command line client to look much better.

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

convert hex to decimal ; decimal to hex

Remove color codes (special characters) with sed

Netstat Connection Check
This command does a tally of concurrent active connections from single IPs and prints out those IPs that have the most active concurrent connections. VERY useful in determining the source of a DoS or DDoS attack.

Make changes in .bashrc immediately available
Simply sourcing .bashrc does not function correctly when you edit it and change an alias for a function or the other way round with the *same name*. I therefor use this function. Prior to re-sourcing .bashrc it unsets all aliases and functions.

Watch the progress of 'dd'
run this in another terminal, were xxxx is the process ID of the running dd process. the progress will report on the original terminal that you ran dd on


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