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List all bash shortcuts
This command shows the various shortcuts that can be use in bash, including Ctrl+L, Ctrl+R, etc... You can translate "\C-y" to Ctrl+y, for example.

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

Convert a script to one-liner
Opposite: Convert an one-liner to script: $ foo() { ; } ... $ typeset -f foo ... $ unset -f foo

View all images
So you are in directory with loads of pictures laying around and you need to quickly scan through them all

Create strong, but easy to remember password
Why remember? Generate! Up to 48 chars, works on any unix-like system (NB: BSD use md5 instead of md5sum)

list block devices
Shows all block devices in a tree with descruptions of what they are.

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"

Execute most recent command containing search string.
Execute the most recent command containing search string. This differs from !string as that only refers to the most recent command starting with search string.

Tricky implementation of two-dimensional array in Bash.
Since Bash doesn't support two-dimensional arrays, you can limit your columns length by some big enough constant value ( in this example 100 ) and then index the array with i and j, or maybe write your own get() and set() methods to index the array properly like I implemented for example ( see Sample output ). For example for i=0 and j=0...99 you'll pick up one of 100 elements in the range [0,99] in the one-dimensional array. For i=1 and j=0...99 you'll pick up one of 100 elements in the range [100,199]. And so on. Be careful when using this, and remember that in fact you are always using one-dimensional array.

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.


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