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e.g. if rm is aliased for 'rm -i', you can escape the alias by prepending a backslash:
rm [file] # WILL prompt for confirmation per the alias
\rm [file] # will NOT prompt for confirmation per the default behavior of the command
when using Gnome or KDE, you will have a hard time getting a screenshot of something like a login screen, or any other screen that occurs before the desktop environment is up and monitoring the printscreen key. (this probably applies for other DEs as well, but I haven't used them)
What this command is meant to do is take a screenshot of an X window using a command you can run from your virtual terminals (actual text terminals, not just an emulator) To do this:
Press CTRL+ALT+F1 to go to a virtual (text) terminal once your login window comes up
Login to the virtual terminal and enter the command (you'll have to type it in)
You should now have a file called screenshot.png in your home directory with your screenshot in it.
For those of you who are new to the virtual terminal thing, you can use CTRL+ALT+F7 to get back to your regular GUI
From http://www.gnome.org
This checks if the branch has been merged with master and then will delete the ones that have been. Keeps your local git repo nice and clean from all the branches.
Searches bash-history in reverse order (last entered commands first). Pressing ctrl+r again shows the next matching entry.
Ever logged into a *nix box and needed to know which webserver is running and where all the current access_log files are? Run this one liner to find out. Works for Apache or Lighttpd as long as CustomLog name is somewhat standard. HINT: works great as input into for loop, like this:
$ for i in `lsof -p $(netstat -ltpn|awk '$4 ~ /:80$/ {print substr($7,1,index($7,"/")-1)}')| awk '$9 ~ /access.log$/ {print $9| "sort -u"}'` ; do echo $i; done
Very useful for triage on unfamiliar servers!
http://public-dns.info gives a list of online dns servers. you need to change the country in url (br in this url) with your country code. this command need some time to ping all IP in list.