Commands by sungam (2)

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function to verify an IP address - can be used at the shell prompt or in a shell script
When processing IP addresses in the shell (or shell script) it is useful to be able to verify that the value of data is an IP address (an not some random string or non-sensible IP address).

Create a directory and change into it at the same time
How often do you make a directory (or series of directories) and then change into it to do whatever? 99% of the time that is what I do. This BASH function 'md' will make the directory path then immediately change to the new directory. By using the 'mkdir -p' switch, the intermediate directories are created as well if they do not exist.

ThePirateBay.org torrent search
usage: tpb searchterm example: tpb the matrix trilogy This searches for torrents from thepiratebay and displays the top results in reverse order, so the 1st result is at the bottom instead of the top -- which is better for command line users

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"

See a full list of compiler defined symbols
From http://lists.debian.org/debian-devel/2001/01/msg00971.html .

This is how you should push a string in a command's stdin.
Don't do this: $echo word | command Using a bash "here strings" and "here documents" look leeter than piping echo into the command. Also prevents subshell execution. Word is also expanded as usual.

Update a namecheap @ A record to point to your current internet-facing IP address
Sets the @ A record for your domain hosted by namecheap to your current internet-facing IP address, logs success or failure with syslog, and logs the data returned to /root/dnsupdate. Change the XXX's as appropriate. More info at: http://www.namecheap.com/support/knowledgebase/article.aspx/29/

find all executable files across the entire tree
I can think of using this command after compiling an downloaded source from anywhere as an easy way to find all executable products. We usually issue the $ find command (without arguments) to list the full paths of all directories and sub-directories and files in the entire current tree. Similar command is $ tree -aicfnF

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.

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


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