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Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.
Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):
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This function is used to set environmental variables from a list of alternatives depending on what's installed on the system. It returns the first program found in the list.
export BROWSER=$(find_alternatives chromium-browser google-chrome opera firefox firefox-bin iceweasel konqueror w3m lynx)
export EDITOR=$(find_alternatives vim nano pico emacs kate)
export PAGER=$(find_alternatives vimpager less most more pg)
Use it with cat and '|' for know what is used in a conf file.
For example cat /etc/squid/squid.conf | sed -re '/^#/d ; s/#.*$// ; /^\s$/d' :
Show you what you use in your file conf.
It removes all comments and empty lines.
Empty lines are lines with nothing, a tab, or a space.
It will produce passwords with length of 20 printable characters within a reasonable time.
For shorter or longer passwords just change the 20 in bs=20 to something more convenient.
To create only alpha numeric passwords change [:print:] to [:alnum:]
tells you the number of lines in said file, and then tail the last 100 lines ( or how many are messed up) then u take the total amount of lines and then subract the 100 or so lines u DONT WANT, then do a head -n $new_number and then redirect it to new file.db
chkrootkit is a tool to locally check for signs of a rootkit,Get it from the website http://www.chkrootkit.org
Convert all Tables from MyISAM to InnoDB
The command line can be accessed by using the cmd command which will open a command window with a DOS interface. The command line is a throw back to the early days of computing before there was a Windows interface.
List of commands you use most often suppressing sudo
Test your XFS filesystem and Raptor hard drives for write performance.
change ":" in path for new line and associate word path to var $PATH
Batch resize all images to a width of 'X' pixels while maintaing the aspect ratio.
This makes uses of ImageMagick to make life easier.
Find and replace specific characters in a single line in multiple files with sed.
Some malicious program appends a iframe or script tag to you web pages on some server, use this command to clean them in batch.
You can replace "sort -nu" with "sort -u" for a word list sorted or "sort -R" for a random-sorted line
Here's a bash version using an array.
NOT MINE! Taken from hackzine.com blog.
It creates a tree-style output of all the (sub)folders and (sub)files from the current folder and down(deeper)
Quoting some of hackzine's words
"Murphy Mac sent us a link to a handy find/sed command that simulates the DOS tree command that you might be missing on your Mac or Linux box. [..split...] Like most things I've seen sed do, it does quite a bit in a single line of code and is completely impossible to read. Sure it's just a couple of substitutions, but like a jack in the box, it remains a surprise every time I run it."
This command allows you to find the effective uid and gid of the Apache process regardless of process name (which can be apache2 or httpd depending on distro).