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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.
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Ever had a file with a list of numbers you wanted to add, use:
cat file | sed ':a;N;$!ba;s/\n/+/g' | bc
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."
populate the auth.hosts file with a list of IP addresses that are authorized to be in use and when you run this command it will return the addresses that are pingable and not in the authorized list.
Can be combined with the "Command line Twitter" command to tweet unauthorized access.
Jan Nelson from Grockit came up with this for us when we needed to rename all of our fixtures.
If run in bash, this will display all executables that are in your current $PATH
This is the result of a several week venture without X. I found myself totally happy without X (and by extension without flash) and was able to do just about anything but watch YouTube videos... so this a the solution I came up with for that. I am sure this can be done better but this does indeed work... and tends to work far better than YouTube's ghetto proprietary flash player ;-)
Replace $i with any YouTube ID you want and this will scrape the site for the _real_ URL to the full quality .FLV file on Youtube's server and will then will hand that over to mplayer (or vlc or whatever you want) to be streamed.
In some browsers you can replace $i with just a % or put this in a shell script so all YouTube IDs can be handed directly off to your media player of choice for true streaming without the need for Flash or a downloader like clive. (I do however fully recommend clive if you wish to archive videos instead of streaming them)
If any interest is shown I would be more than happy to provide similar commands for other sites. Most streaming flash players use similar logic to YouTube.
Edit: 05/03/2011 -
Updated line to work with current YouTube. It could be a lot prettier but I will probably follow up with another update when I figure out how to get rid of that pesky Grep. Sed should take that syntax... but it doesn't.
Original (no longer working) command:
mplayer -fs $(echo "http://youtube.com/get_video.php?$(curl -s $youtube_url | sed -n "/watch_fullscreen/s;.*\(video_id.\+\)&title.*;\1;p")")
Suppose you made a backup of your hard disk with dd:
dd if=/dev/sda of=/mnt/disk/backup.img
This command enables you to mount a partition from inside this image, so you can access your files directly.
Substitute PARTITION=1 with the number of the partition you want to mount (returned from sfdisk -d yourfile.img).
This download a complete audio podcast
recursively traverse the directory structure from . down, look for string "oldstring" in all files, and replace it with "newstring", wherever found
grep -rl oldstring . |xargs perl -pi~ -e 's/oldstring/newstring'
This is a quick line to stream in the latest offerings of your favorite netcasts/podcasts. You will need to have a file named netcast.txt in the directory you run this from. This file should have one and only one of your netcast's/podcst's url per line.
When run the line grabs the offering on the top of the netcast/podcast stack and end it over , quietly, to vlc.
Since I move around computers during the day I wanted an easy way to listen to my daily dose of news and such without having to worry about downloading to whatever machine I am on. This is just a quick grab and stream of whats current.
Future plans... have the list of netcasts be read from the web. possibly an rss or such. I use greader so there might be a way to use it as the source so as not to have to muck with multiple lists
These part of the command:
svn status | grep '^\?' => find new file or directory on working copy
sed -e 's/^\?//g' => remove "^" character on the first character of file name
xargs svn add => add file to subversion repository
You can modify above command to other circumtances, like revert addition files or commit files that have been modified. ^_^
This command will list a CSV list of infected files detected by clamav through squidclamav redirector.
Scans the file once to build a list of line numbers that contain non-printable characters
Scans the file again, passing those line numbers to sed as two commands to print the line number and the line itself. Also passes the output through a tr to replace the characters with a ?
queries local memcached for stats, calculates hit/get ratio and prints it out.
Note that the file at the given path will have the contents of the (still) deleted file, but it is a new file with a new node number; in other words, this restores the data, but it does not actually "undelete" the old file.
I posted a function declaration encapsulating this functionality to http://www.reddit.com/r/programming/comments/7yx6f/how_to_undelete_any_open_deleted_file_in_linux/c07sqwe (please excuse the crap formatting).