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Convert ascii string to hex
Converts the ascii text to hex from bash. Check the sample output.

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

Find and remove core files

!* Tells that you want all of the *arguments* from the previous command to be repeated in the current command
Example: touch file{1,2,3}; chmod 777 !*

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

Averaging columns of numbers
This example calculates the averages of column one and column two of "file.dat". It can be easily modified if other columns are to be averaged.

Backup all MySQL Databases to individual files

April Fools' Day Prank
Add this to a fiend's .bashrc. PROMPT_COMMAND will run just before a prompt is drawn. RANDOM will be between 0 and 32768; in this case, it'll run about 1/10th of the time. \033 is the escape character. I'll call it \e for short. \e7 -- save cursor position. \e[%d;%dH -- move cursor to absolute position \e[4%dm \e[m -- draw a random color at that point \e8 -- restore position.

Discover the process start time
That is useful to discover the start time of process older than 1 day. You can also run: $ ls -ld /proc/PID That's returning the creation date of the proc files from the process. Some users reported that this way might show you a wrong date since any other process like cron, for example, could change this date.

Install pip with Proxy
Installs pip packages defining a proxy


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