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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.
» http://twitter.com/commandlinefu
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Also shows files as they are found. Only works from a tty.
while commandt
do
command
command
...
done
{commandt is executed and its exit status tested.}
for i in 1 2 3
> do
> echo $i
> done
Use `scsi_id` to positively identify which LUNs are which (i.e. compare with the list of LUNs you created on your disk array)
(shown: RHEL5 usage)
Debian usage:
# for i in /dev/sd* ; do wwn=`/lib/udev/scsi_id -g --device $i` ; [ "$wwn" != "" ] && echo -e ${i##*/}'\t'$wwn ;done
This is the fastest way to burn a DVD-Video from the command line.
Dependencies:
libav-tools
dvdauthor
growisofs
The first command:
avconv -i input.avi -target pal-dvd dvd.mpg
converts any given video file avconv can handle into MPEG2-PS (6 Mbit/s) with AC3 audio (448 kbit/s). If your distribution is not up to date, just use ffmpeg - the syntax is the same. Hint: If you want to create an NTSC DVD, type ntsc-dvd instead ;-)
The second command:
echo PAL > ~/.config/video_format
sets PAL as your default video format. This is a workaround for an old dvdauthor bug. If you want NTSC, guess what? Type NTSC instead!
The third command:
dvdauthor -o dvd/ -t dvd.mpg
creates .VOB files and adds them to the dvd/ folder. You don't have to create this folder yourself. You can add as many titles as you like, just keep in mind that there's a maximum of 4482 MiB (4.37 GiB) for normal DVDs.
The fourth command:
dvdauthor -o dvd/ -T
finishes the DVD-Video.
Now you can burn your DVD using growisofs:
growisofs -Z /dev/dvd -dvd-video dvd/
Sources:
manpages
http://tuxicity.wordpress.com/2006/12/01/avi-to-dvd-with-ffmpeg-and-dvdauthor/
This will take the packages matching a given `apt-cache search` query (a collection of AND'd words or regexps) and tell you how popular they are. This is particularly nice for those times you have to figure out which solution to use for e.g. a PDF reader or a VNC client.
Substitute "ubuntu.com" for "debian.org" if you want this to use Ubuntu's data instead. Everything else will work perfectly.
Now we can capture only a specific window (we have to chose by clicking on it)
ffmpeg complains about "Frame size must be a multiple of 2" so we calculate the upper even number with (g)awk trickery.
We remove the grep, we are already using (g)awk here ....why losing time with grep !!! ;)
The command will make it easy to determine free IP ranges in a crowded sub-net.
Never ending music, generated via a C snippet, piped to aplay. Taken from: http://canonical.org/~kragen/bytebeat/
This will parse a random command json entry from http://commandlinefu.com
A must have in your .bash_profile to learn new shell goodies at login!!!
Echoes text horizontally centralized based on screen width
usage: alarmclock TIME
TIME is a sleep(1) parameter which tells function how long to wait until raise the alarm.
*I run this with byobu as as a custom status bar entry that runs every 10 seconds by putting it in a script here:
.byobu/bin/10_update_windows
There's no output to stdout, so nothing is displayed on the status bar.
*Presumes that #{pane_title} is set to the hostname or prompt containing the host name. In my case, it's in this format:
$USER@$HOSTNAME:$PWD
The sed commands may need to be modified if your pane_title is different.
*If you want to strip out a common part of a hostname, add the following before '| uniq'
-e 's/[COMMON PART]//'
I use that to strip out the domain of the servers I connect to, leaving the subdomain.
Use if you want to include untrusted literal strings in your grep regexes.
I use it to list all mounts below a directory:
dir=/mnt/gentoo; cat /proc/mounts |awk '{print $2}' |egrep "^$(egrep_escape "$dir")(/|$)"
/mnt/gentoo
/mnt/gentoo/proc
/mnt/gentoo/sys
/mnt/gentoo/dev
/mnt/gentoo/home
Works even if $dir contains dangerous characters (e.g. comes from a commandline argument).
You can execute this inside an editor to get all the fields inside your buffer and do the magic, really usefull when your tables contain a giant list of fields.
This version combines the best of the other suggestions and adds these features:
1. It scans a /16 subnet
2. It is very fast by running the ping commands in the background, running them in parallel.
3. Does not use the "-W" option as that's not available in older ping versions (I needed this for OS X 10.5)
It executes commands as arguments to ssh, avoiding problematic shell expansions, without the need of writing the commands in question to a temporary file, just reading them from STDIN.
This command clones an image three times and creates a 'tile' image that can be used for a repeating pattern wallpaper. Add 'rm $f $of $off' to the end for cleanup (command was too long to submit with it).
See this link for an example: http://meathive.deviantart.com/art/Easy-Photography-Hack-314846774