Commands by vaporub (7)

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Generate random valid mac addresses
Python Alternative

Get a list of the erroring cifs entries in fstab
It disturbs me when my logwatch report tells me a share or machine has disappeared, esp as mount isn't telling me what's gone. This command outputs to stderr the erroring cifs entries from fstab.

resize all JPG images in folder and create new images (w/o overwriting)
Convert all jpegs in the current directory into ~1024*768 pixels and ~ 150 KBytes jpegs

Lists all files and directories with modified time newer than a given date
This is great for looking for files that have been updated recently. Logs especially or monitoring what files were added during an install.

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"

Check if your ISP is intercepting DNS queries
It's somewhat common ISPs to intercept DNS queries at port 53 and resolve them at their own. To check if your ISP is intercepting your DNS queries just type this command in the terminal. "#.abc" it's an OK answer. But if you get something like "I am not an OpenDNS resolver.", yep, you are beign cheated by your ISP.

find . -name

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"

Compression formats Benchmark
See: http://imgur.com/JgjK2.png for example. Do some serious benchmarking from the commandline. This will write to a file with the time it took to compress n bytes to the file (increasing by 1). Run: $ gnuplot -persist

Get the time since epoch
Get the time since epoch. Useful when working with commands and logs which use this format.


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