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There is no need for variables. I also added sleep to reduce cpu usage, however I didn't test it.
Of course, a fifo is required for piloting the fade out of another song, but with a few bash function, we can mix music in bash like :
crossfadeIn > mplayerfifo1 & crossfadeOut > mplayerfifo2
loop 0 10 > mplayer fifo1
can also be invoked as 'exipick -zi | exim -dM' if you do not need/want the delay between flushes.
I often use it to find recently added ou removed device, or using find in /dev, or anything similar.
Just run the command, plug the device, and wait to see him and only him
Adjust "sleep X" to your needs.
*NOTE: First sleep is required because bash doesn't have a "post-test" syntax (do XXX while).
Is a simple script for video streaming a movie
restart a buggy script when it dies. works great for "git svn fetch", which leaks memory like a sieve and eventually dies...making you restart it.
use this comand to see which switch port your network interface is using.
but remind, there is no network traffic for 10 minutes or how long you run the comand.
if you start the comand via ssh, port will come up again after the "for loop" has endet
This is useful if you'd like to see the output of a script while you edit it. Each time you save the file the command is executed. I thought for sure something like this already exists - and it probably does. I'm on an older system and tend to be missing some useful things.
ontouchdo yourscript 'clear; yourscript somefiletoparse'
Edit yourscript in a separate window and see new results each time you save.
ontouchdo crufty.html 'clear; xmllint --noout crufty.html 2>&1 | head'
Keep editing krufty.html until the xmllint window is empty.
Note: Mac/bsd users should use stat -f%m. If you don't have stat, you can use perl -e '$f=shift; @s=stat($f); print "$s\n";' $1
Cycles continuously through a string printing each character with a random delay less than 1 second. First parameter is min, 2nd is max. Example: 1 3 means sleep random .1 to .3. Experiment with different values. The 3rd parameter is the string. The sleep will help with battery life/power consumption.
cycle 1 3 $(openssl rand 100 | xxd -p)
Fans of "The Shining" might get a kick out of this:
cycle 1 4 ' All work and no play makes Jack a dull boy.'
This will turn it in an infinite loop and also shows random words from a file, so it won't be the same each time and also not just a number.
Create a progress dialog with custom title and text using zenity.
using seq inside a subshell instead of a bash sequence to create increments.
Not as taxing on the CPU.
Dialog's gauge widget accepts progress updates on stdin. This version runs dialog once and updates it every second.
There's no need to use timeout which causes screen flicker since it restarts dialog for each update.
ls largedir |rd
lynx -dump largewebsite.com |rd
rd < largelogfile
This is like ping -a, but it does the opposite. It alerts you if the network is down, not up. Note that the beep will be from the speaker on the server, not from your terminal.
Once a second, this script checks if the Internet is accessible and beeps if it is not. I define the Net as being "UP", if I can ping Google's public DNS server (188.8.131.52), but of course you could pick a different static IP address. I redirect the beep to /dev/console so that I can run this in the background from /etc/rc.local. Of course, doing that requires that the script is run by a UID or GID that has write permissions to /dev/console (usually only root).
Question: I am not sure if the -W1 flag works under BSD. I have only tested this under GNU/Linux using ping from iputils. If anybody knows how portable -W is, please post a comment.
enable each bash completion that you have installed at your system, that's very nice ;)
Thank You, hackerb9!
In general, this is actually not better than the "scrot -d4" command I'm listing it as an alternative to, so please don't vote it down for that. I'm adding this command because xwd (X window dumper) comes with X11, so it is already installed on your machine, whereas scrot probably is not. I've found xwd handy on boxen that I don't want to (or am not allowed to) install packages on.
NOTE: The dd junk for renaming the file is completely optional. I just did that for fun and because it's interesting that xwd embeds the window title in its metadata. I probably should have just parsed the output from file(1) instead of cutting it out with dd(1), but this was more fun and less error prone.
NOTE2: Many programs don't know what to do with an xwd format image file. You can convert it to something normal using NetPBM's xwdtopnm(1) or ImageMagick's convert(1). For example, this would work: "xwd | convert fd:0 foo.jpg". Of course, if you have ImageMagick already installed, you'd probably use import(1) instead of xwd.
NOTE3: Xwd files can be viewed using the X Window UnDumper: "xwud <foo.xwd". ImageMagick and The GIMP can also read .xwd files. Strangely, eog(1) cannot.
NOTE4: The sleep is not strictly necessary, I put it in there so that one has time to raise the window above any others before clicking on it.
very handy if you copy or download a/some file(s) and want to know how big it is at the moment
You can use this one-liner for a quick and dirty (more customizable) alternative to the watch command. The keys to making this work: everything exists in an infinite loop; the loop starts with a clear; the loop ends with a sleep. Enter whatever you'd like to keep an eye on in the middle.
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