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Comcast is an ISP in the United States that has started hijacking DNS requests as a "service" for its customers. For example, in Firefox, one used to be able to do a quick "I'm Feeling Lucky" Google search by typing a single word into the URL field, assuming the word is not an existing domain when surrounded by www.*.com. Comcast customers never receive the correct NX (non-existent domain) error from DNS. Instead, they are shown a page full of advertising. There is a way to "opt out" from their service, but that requires having the account password and the MAC address of your modem handy. For me, it was easier just to set static DNS servers. But the problem is, which ones to choose? That's what this command answers. It'll show you the three _non-hijacked_ Comcast DNS servers that are the shortest distance away.
Perhaps you don't have Comcast (lucky you!), but hopefully this command can serve as an example of using netselect to find the fastest server from a list. Note that, although this example doesn't show it, netselect will actually perform the uniq and DNS resolution for you.
Requires: netselect, curl, sort, uniq, grep
Col 1 is swapped sum in kb
Col 2 is pid of process
Col 3 is command that was issued
** Replace the ... in URLS with:
Couldn't fit in 256
Created on Ubuntu 9.10 but nothing out of the ordinary, should work anywhere with a little tweaking. 5163 is the number of unique first names you get when combine the male and female first name files from. http://www.census.gov/genealogy/www/data/1990surnames/names_files.html
i wanted to delete all duplicate lines from .bash_history and keep the order of the other lines.
the command cat's the file and adds line numbers, then sorts by the second column. afterwards uniq omits repeated lines, but skips the first field (the line number). then it sorts by the line numbers and at the end cuts the numbers off.
To see only earthquakes for today, add another pipe to egrep "`date '+%Y/%m/%d'`"
This should work even if the output format changes.
Searches all log files (including archived bzip2 files) for invalid user and PAM authentication errors, both of which are indicative of brute force attempts at logging into computer. A list of all unique IP addresses and domain names is appended to hosts.deny. The command (and grep error messages) will work on Mac OS X 10.6, small adjustments may be needed for other OSs.
Avoids creating useless directory entries in archive, and sorts files by (roughly) extension, which is likely to group similar files together for better compression. 1%-5% improvement.
GNU find + sort
no fancy grep stuff here.
Uses the dumb terminal option in gnuplot to plot a graph of frequencies. In this case, we are looking at a frequency analysis of words in all of the .c files.
handles file names with spaces and colons, fixes sort (numeric!), uses mplayer, same output format as other alternatives
Similar but using mediainfo instead of totem-something
Sort .avi movies by time length, print the longest first, and so on...
Since coreutils 7.6 provides sort -h
You'll run into trouble if you have files w/ missing newlines at the end. I tried to use
PAGER='sed \$q' git blame
PAGER='sed \$q' git -p blame
to force a newline at the end, but as soon as the output is redirected, git seems to ignore the pager.
Figures out total line contribution per author for an entire GIT repo. Includes binary files, which kind of mess up the true count.
If crashes or takes too long, mess with the ls-file option at the start:
git ls-files -x "*pdf" -x "*psd" -x "*tif" to remove really random binary files
git ls-files "*.py" "*.html" "*.css" to only include specific file types
Based off my original SVN version: http://www.commandlinefu.com/commands/view/2787/prints-total-line-count-contribution-per-user-for-an-svn-repository
note the xargs at the end