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Getting a domain from url, ex: very nice to get url from squid access.log

Find the package that installed a command

Run a bash script in debug mode, show output and save it on a file
Sends both stdout and stderr to the pipe which captures the data in the file 'out.test' and sends to stdout of tee (likely /dev/tty unless redirected). Works on Bourne, Korn and Bash shells.

Join lines
Even shorter. Stolen from comment posted by eightmillion.

validate the syntax of a perl-compatible regular expression
Place the regular expression you want to validate between the forward slashes in the eval block.

uniq for unsorted data

Alias to edit and source your .bashrc file
Place the line above in your ~/.bahsrc file. Now every time you issue the 'vb' command, you invoke the vim editor to edit it, then source it so the changes take effect immediately. Notes: * This mechanism is not working well if your .bashrc contains commands that should not be sourced more than once. * This trick also work for your csh or tclsh users: place the following line in your ~/.cshrc file: alias vc 'vim ~/.cshrc; source ~/.cshrc Thank you adzap for pointing out the missing quote

List only directories, one per line
omit the 1 (one) if you don't need one-per-line

Backup trought SSH

Fill a hard drive with ones - like zero-fill, but the opposite :)
Note: Replace 200000 with drive bytes/512, and /dev/sdx with the destination drive/partition. ;) Note: You may need to install pipebench, this is easy with "sudo apt-get install pipebench" on Ubuntu. The reason I hunted around for the pieces to make up this command is that I wanted to specifically flip all of the bits on a new HDD, before running an Extended SMART Self-Test (actually, the second pass, as I've already done one while factory-zeroed) to ensure there are no physical faults waiting to compromise my valuable data. There were several sites that came up in a Google search which had a zero-fill command with progress indicator, and one or two with a fill-with-ones command, but none that I could find with these two things combined (I had to shuffle around the dd command(s) to get this to happen without wasting speed on an md5sum as well). For reference, these are the other useful-looking commands I found in my search: Zero-fill drive "/dev/sdx", with progress indicator and md5 verification (run sudo fdisk -l to get total disk bytes, then divide by 512 and enter the resulting value into this command for a full wipe) $ dd if=/dev/zero bs=512 count= | pipebench | sudo tee /dev/sdx | md5sum And this command for creating a file filled with ones is my other main source (besides the above command and man pages, that is - I may be a Linux newbie but I do read!): $ tr '\000' '\377' < /dev/zero | dd of=allones bs=1024 count=2k Hope someone finds this useful! :) Cheers, - Gliktch


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