Commands by rlinux57 (1)

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Send an email from the terminal when job finishes
Might as well include the status code it exited with so you know right away if it failed or not.

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

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).

Text graphing ping output filter
Nasty perl one-liner that provides a sparkline of ping times. If you want a different history than the last 30, just put that value in. It (ab)uses unicode to draw the bars, inspired by https://github.com/joemiller/spark-ping . It's not the most bug-free piece of code, but what it lacks in robustness it makes up for in capability. :) If anyone has any ideas on how to make it more compact or better, I'd love to hear them. I included a ping to google in the command just as an example (and burned up 10 chars doing it!). You should use it with: $ ping example.com | $SPARKLINE_PING_COMMAND

Create user add lines from partial passwd file
Handy if you are installing a new server or recovering an old one and you have a passwd file with the accounts you want to add to the server. If you edit the file so that only the accounts that you want to add are left this line will spit out the correct useradd lines. The uid, gecos and shell will be preserved.

live netcat network throughput test
On the another machine write this command. pv -r /dev/zero | nc 192.168.1.1 7777 It will show live throughput between two machine.The destination machine ip is at our example 192.168.1.1 You must multiply by 8 for the network calculation. You must install pv and netcat commands for this commands usage. kerim@bayner.com http://www.bayner.com/

Display last exit status of a command
The variable ? contain the last exit status of a command, it can be printed for troubleshooting purpose.

Migrate Server with rsync
Copies the complete root-dir of a linux server to another one, where the new harddisks formated and mountet. Very useful to migrate a root-server to another one.

Generate list of words and their frequencies in a text file.

Link a deep tree of files all into on directory
If you want to pull all of the files from a tree that has mixed files and directories containing files, this will link them all into a single directory. Beware of filesystem files-per-directory limits.


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