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

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

find files ignoring .svn and its decendents

rot13 simple substitution cipher via command line
E.g. Useful for hiding spoilers in reviews, etc.

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

Grep syslog today last hour
Uses date to grep de logfile for today and uses it to get the last hour logs. Can be used to get last minute logs or today's logs.

tar+pbzip2 a dir

convert wav into mp3 using lame

Make sure your script runs with a minimum Bash version
If you use new features of a certain Bash version in your shell script, make sure that it actually runs with the required version.

Efficiently extract lines between markers
GNU Sed can 'address' between two regex, but it continues parsing through to the end of the file. This slight alteration causes it to terminate reading the input file once the STOP match is made. In my example I have included an extra '/START/d' as my 'start' marker line contains the 'stop' string (I'm extracting data between 'resets' and using the time stamp as the 'start'). My previous coding using grep is slightly faster near the end of the file, but overall (extracting all the reset cycles in turn) the new SED method is quicker and a lot neater.


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