commandlinefu.com is the place to record those command-line gems that you return to again and again.
Delete that bloated snippets file you've been using and share your personal repository with the world. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.
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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,…):
Subscribe to the feed for:
Change the number to change the number of spaces. Leaving it out defaults to 8. Leaving out the filename defaults to stdin.
And to do it in reverse, you can use the unexpand command.
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.
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 actually do the same thing with a combination of head and tail. For example, in a file of four lines, if you just want the middle two lines:
head -n3 sample.txt | tail -n2
Line 1 --\
Line 2 } These three lines are selected by head -n3,
Line 3 --/ this feeds the following filtered list to tail:
Line 2 \___ These two lines are filtered by tail -n2,
Line 3 / This results in:
being printed to screen (or wherever you redirect it).
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."