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Break lines after, for example 78 characters, but don't break within a word/string
Per default, linux/unix shells are configured with a width of 80 characters. If you like to edit a phrase or string on a line with more than 80 characters it might take long to go there (for example a line with 1000 characters and you like to edit the 98th word which is character 598-603). Maybe you might wish to use 78 characters, because if you forward the text via mail and the text will be quoted (2 extra characters at the beginning to the line "> "), you use 80 characters, otherwise 82, which are lame.

Post a message to another users screen via SSH
Post a message on another users screen via SSH

Convert unix timestamp to date

urldecoding
My version uses printf and command substitution ($()) instead of echo -e and xargs, this is a few less chars, but not real substantive difference. Also supports lowercase hex letters and a backslash (\) will make it through unescaped

Make a high definition VNC
-nohttpd don't run mini-httpd if VNC java applet is found -name change the name of the desktop, it's passed to xstartup script via $VNCDESKTOP, run different set of apps acording the name. -depth pixel depth in bits of the desktop, default is 16 -geometry size of the desktop, default is 1024x768

Define a quick calculator function
POSIX compliant arithmetic evaluation. = 10*2+3

Benchmark SQL Query
Benchmark a SQL query against MySQL Server. The example runs the query 10 times, and you get the average runtime in the output. To ensure that the query does not get cached, use `RESET QUERY CACHE;` on top in the query file.

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

Extract neatly a rar compressed file
It's also possible to delay the extraction (echo "unrar e ... fi" |at now+20 minutes) wich is really convenient!

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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