Commands by kenyon (0)

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Convert all MySQL tables and fields to UTF8
This loops through all tables and changes their collations to UTF8. You should backup beforehand though in case some data is lost in the process.

Create QR codes from a URL.
QR codes are those funny square 2d bar codes that everyone seems to be pointing their smart phones at. Try the following... $ qrurl http://xkcd.com Then open qr.*.png in your favorite image viewer. Point your the bar code reader on your smart phone at the code, and you'll shortly be reading xkcd on your phone. URLs are not the only thing that can be encoded by QR codes... short texts (to around 2K) can be encoded this way, although this function doesn't do any URL encoding, so unless you want to do that by hand it won't be useful for that.

BourneShell: Go to previous directory
cd - would return to the previous directory of your cd command. NB: previous dir is always stored in $OLDPWD variable.

Getting a domain from url, ex: very nice to get url from squid access.log

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

find co-ordinates of a location
Just add this to your .bashrc file. Use quotes when query has multiple word length.

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

Print a horizontal line

Start dd and show progress every X seconds
Adjust "sleep X" to your needs. *NOTE: First sleep is required because bash doesn't have a "post-test" syntax (do XXX while).

Save a file you edited in vim without the needed permissions
I often forget to sudo before editing a file I don't have write permissions on. When you come to save that file and get the infamous "E212: Can't open file for writing", just issue that vim command in order to save the file without the need to save it to a temp file and then copy it back again.


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