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Truncate long strings in columns and use custom header names
Using the --table-truncate ( -T ) option, you can specify the columns you will allow to be truncated. This helps when you have some columns that are unusually long, or a small terminal window. In this example we will print out the /etc/passwd file in columns. We are using a colon as our separator ( -s: ), defining that we want table output ( -t ), defining the column names ( -N ) and allowing the column NAME to be truncated ( -T ).

Expedient hard disk temprature and load cycle stats
This command is a great way to check to see if acpi is doing damage to your disks by agressivly parking the read arm and wearing down it's life. As you can see, mine has lost half its life. I'm sure this could be shortened though somehow. It will use smartctl to dump the stats and then grep out just the temperature and load cycles for the disk (a load cycle is when a the read arm comes out of park and wears on the drive).

grep -v with multiple patterns.
Use multiple patterns with grep -v. So you can print all lines in a file except those containing the multiple patterns you specify.

Are there any words in the English language that use at least half of the alphabet without repeating any letters?
This is the most straightforward approach: first regexp limits dictionary file to words with thirteen or more characters, second regexp discards any words that have a letter repeated. (Bonus challenge: Try doing it in a single regexp!)

find files in a date range
Find files in a specific date range - in this case, the first half of last year. -newermt = modification time of the file is more recent than this date GNU find allows any date specfication that GNU date would accept, e.g. $ find . -type f -newermt "3 years ago" ! -newermt "2 years ago" or $ find . -type f -newermt "last monday"

check open ports without netstat or lsof

Combine cssh and shell expansion to execute commands on a large cluster
This will open an awful lot of little windows, but is quite useful if you want to quickly patch something on a cluster of servers.

get all pdf and zips from a website using wget
If the site uses https, use: $ wget --reject html,htm --accept pdf,zip -rl1 --no-check-certificate https-url

statistics in one line
In this example, file contains five columns where first column is text. Variance is calculated for columns 2 - 5 by using perl module Statistics::Descriptive. There are many more statistical functions available in the module.

Script Terminal Session
script -f /tmp/foo will place all output of the terminal, including carriage returns, to a file. This file can be tail dash-eff'ed by one or more other terminals to display the information of the main terminal. Good way to share one's screen on short notice. Note: This produces a very accurate output, but that includes depending on the size of your terminal to be the same. You can clear screens or even resize the terminal for others using this function; I use it in conjunction with the "mid" command in my list.


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