Bash script: Loop command,

Hi all,
I need a bit of help looping a command on a bash script,
please see below the command I need to loop:
ffmpeg -s 2720x1024 -r 25 -f x11grab -i :0.0 -acodec libmp3lame -ab 128k -vcodec mpeg4 -sameq -y -t 60 /media/z/.cam/screen/screen_`date +%F_%T`.avi
So basically I record my screen for a period of 1 minutes and the process once done need to restart.
I have search on how to loop the command but I must admit it seem rather complicated, so for the time being I added && at the end and paste the command a lot...
Any help would be appreciated,
Many thanks,
Regards

sweetthdevil wrote:ffmpeg -s 2720x1024 -r 25 -f x11grab -i :0.0 -acodec libmp3lame -ab 128k -vcodec mpeg4 -sameq -y -t 60 /media/z/.cam/screen/screen_`date +%F_%T`.avi
I recommend using the FFmpeg commands shown here:
How to do Proper Screencasts on Linux Using FFmpeg
It's a well-written guide and the author, verb3k, keeps it up to date which is essential when working with FFmpeg. Compared to your command the output will probably look better. The command from the guide will also probably be closer to your requested frame rate because the lossless output should be easier for the CPU to deal with and the command utilizes the -threads option. Lastly, the -sameq option should not be used. The documentation is misleading and should read something like, "use same quantizer as source" instead of "use same video quality as source". Use of the same quantizer does not mean same quality, and this option especially should not be used when the source and output formats do not share the same quantizer scale.
Last edited by DrZaius (2011-03-27 00:31:46)

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Last edited by panosk (2009-11-08 21:55:31)

oops, brain fart. *flushes with embarrassment*
-- Edit --
BTW, for this kind of thing, I usually do something like:
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Or put those in an array:
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The later method is useful when elements of "${files[@]}" will be used multiple times across the script.
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There's a few ways to do this. Here's two (pick the method you like):
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Salut,
as netcfg2 does not work with my wireless connection, I have to set up the connection manually. For not having to type in the commands every time, I created a bash script.
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Ramses de Norre wrote:How do you know it isn't? What exactly does happen?
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Well what do you think of this Bash script
It works
I gave it some problems (i.e. unpluged the ethernet, messed up the URL's, uninstaled some programs...) to see if would report errors and stop or just keep going... But it did
I just kind of thought up a way to do some error checking with the commands that I know.....
What is a better way to do error checking?
What do you think I should add/Do to this script?
#!/bin/bash
# Shell script to make a USB Tumb Drive for Flashing BIOS on a Lenovo Ideapad Y510.
# This script needs to be owned and run as ROOT with the "sudo command"
# i.e. sudo usbbiosflasher
# If you have anyideas send me a PM on ubuntufourms.org my user name is HunterThomson
# Name/Rename this script usbbiosflasher and save it to the ~/home directory.
# Then run the command- chown root:root usbbiosflasher
# Then run the command- chmod 755 usbbiosflasher
# Then copy the script to the directory /usr/bin.
# Run this comand to do that- sudo cp ~/usbbiosflasher /usr/bin
# You also must have the program "mbr" installed
# You can install the mbr program by running this comand in the shell on Ubuntu
# sudo apt-get install mbr
# In Arch Linux you have to get it from Aur
# First you will need to know a few things...
# You will also need to know the Mount Point i.e. /media/disk and the /dev path i.e. /dev/sdb1.
# You can find these by using the df -T comand.
# Run df -T in the shell. Then plug in the USB Thumb Drive and run the df -T comand agin.
# The new listing is the USB Thumb Dirve.
# Also check to make sure the File System tipe is vFAT or FAT16 or FAT32.
# If it is not use gparted to format it to FAT32.
# I am farly certen that all USB Thumb drives come formated with FAT file system out of the BOX.
# You may want to fromat it anyway just to make sure.
echo "Interactive Shell Script to Make a USB Thumb Drive \for Flashing BIOS On a Lenovo Ideapad Y510"
echo ""
echo "You will need to have the program mbr installed"
echo "If you are on Ubuntu Linux you can retreve it form the repositories"
echo "If you are on Arch Linux you will need to get it from the Aur repository"
echo "Open anuther shell and \do that now..."
echo ""
verify="n"
while [ "$verify" != y ]
do
printf "Do you have mbr installed... yes or no?"
read AN1
echo ""
printf "You answered... $AN1 I have installed mbr. Is this correct... y or n?"
read verify
done
echo ""
if [ "$AN1" == "no" ]
then
echo "Install mbr now. Then run this script agin"
exit
else
echo "contunuing script"
fi
echo ""
# The next comand will make a directory to put needed files into. Note this file and everything init will be owned by root.
mkdir ~/usbbiosfiles && check1="yes"
if [ "$check1" = "yes" ]
then
echo "Made directory usbbiosfiles... OK"
else
echo "Could not \make directory usbbiosfiles"
echo "look above \for \info"
echo "Fix the problem and run this scrip agin"
exit
fi
# The next two comands will get the FreeDOS file and the .ROM file.
cd ~/usbbiosfiles && checka="yes"
if [ "$checka" = "yes" ]
then
echo "Changing to the usbbiosfiles directory... OK"
else
echo "Could not Change to the usbbiosfiles directory"
echo "look above \for \info"
echo "Fix the problem and run this scrip agin"
echo ""
echo "removeing directory usbbiosfiles..."
echo ""
rm -r ~/usbbiosfiles
exit
fi
wget "http://www.fdos.org/bootdisks/autogen/FDOEM.144.gz" && check2="yes"
if [ "$check2" = "yes" ]
then
echo "Download of FreeDOS... OK"
else
echo "Could not Download FreeDOS"
echo "look above \for \info"
echo "Fix the problem and run this scrip agin"
echo ""
echo "removeing directory usbbiosfiles..."
echo ""
rm -r ~/usbbiosfiles
exit
fi
wget "http://ubuntuforums.org/attachment.php?attachmentid=78460&d=1216648756" && check3="yes"
if [ "$check3" = "yes" ]
then
echo "Download of the BIOS.ROM \file... OK"
else
echo "Could not Downlad the BIOS.ROM \file"
echo "look above \for \info"
echo "Fix the problem and run this scrip agin"
echo ""
echo "removeing directory usbbiosfiles..."
echo ""
rm -r ~/usbbiosfiles
exit
fi
# The next comand will name the .ROM file to the right name.
mv ~/usbbiosfiles/attachment.php?attachmentid=78460\&d=1216648756 ~/usbbiosfiles/06CN29WW.bios.update.tar.bz2 && check4="yes"
if [ "$check4" = "yes" ]
then
echo "Renameing of the BIOS.ROM \file... OK"
else
echo "Could not rename the BIOS.ROM \file"
echo "look above \for \info"
echo "Fix the problem and run this scrip agin"
echo ""
echo "removeing directory usbbiosfiles..."
echo ""
rm -r ~/usbbiosfiles
exit
fi
echo ""
# The next two comands set the variables. DEVX for the path i.e. /dev/xxx and MOUNTX for the mount point i.e. /media/xxx
verify="n"
while [ "$verify" != y ]
do
echo "You will need to know the Mount Point and the dev Path. You will also need to \make sure the File System \type is vFAT, FAT16 or FAT32."
echo ""
echo "With the USB Thumb Drive unpluged, Open another shell and run the comand df -T Then plug \in the USB Thumb Drive and run the comand df -T one \more time. The new device listed is the USB Thumb Drive. Note the Mount Point and The dev Path and the File system Type i.e. vFAT... If the File System \type is not vFAT, FAT16 or FAT32 you will need to fromat it with gparted. You may want to format the USB Thumb Drive anyway just to \make sure. In any \case delete all files and directorys on the USB drive before you go any ferther with this program."
echo ""
printf "Enter the dev path the USB Thumb Drive is at?"
read DEVX
echo ""
echo "Are you sure $DEVX is the dev path of the USB Thumb Drive... y or n?"
read verify
done
echo ""
verify="n"
while [ "$verify" != y ]
do
printf "What is the Mount Point of the USB Thumb Drive?"
read MOUNTX
echo ""
echo "Are you sure $MOUNTX is the Mount Point of the USB Drive... y or n?"
read verify
done
echo ""
install-mbr --enable A1 --partition 1 --force --timeout 0 $DEVX && check5="yes"
if [ "$check5" = "yes" ]
then
echo "Installing MBR on USB Thumb Dirve... OK"
else
echo "Could not install MBR on USB Thumb Drive"
echo "look above \for \info"
echo "Fix the problem and run this scrip agin"
echo ""
echo "removeing directory usbbiosfiles..."
echo ""
rm -r ~/usbbiosfiles
exit
fi
tar xjf ~/usbbiosfiles/*.tar.bz2 && check7="yes"
if [ "$check7" = "yes" ]
then
echo "Unpacking BIOS.ROM file... OK"
else
echo "Could not unpack BIOS.ROM file"
echo "look above \for \info"
echo ""
echo "Reformat the USB Stick to FAT32 with gparted"
echo "Fix the problem and run this scrip agin"
echo ""
echo "removeing directory usbbiosfiles..."
echo ""
rm -r ~/usbbiosfiles
exit
fi
gunzip ~/usbbiosfiles/FDOEM.144.gz && check8="yes"
if [ "$check8" = "yes" ]
then
echo "Unpacking FreeDOS files... OK"
else
echo "Could not unpack FreeDOS files"
echo "look above \for \info"
echo ""
echo "Reformat the USB Stick to FAT32 with gparted"
echo "Fix the problem and run this scrip agin"
echo ""
echo "removeing directory usbbiosfiles..."
echo ""
rm -r ~/usbbiosfiles
exit
fi
mkdir ~/usbbiosfiles/fdoem144 && check9="yes"
if [ "$check9" = "yes" ]
then
echo "Made directory fdoem144 in direcoty usbbiosfiles... OK"
echo ""
echo "Going to \sleep \for 5secs"
else
echo "Could not make directory fdoem144 in usbbiosfiles directory"
echo "look above \for \info"
echo ""
echo "Reformat the USB Stick to FAT32 with gparted"
echo "Fix the problem and run this scrip agin"
echo ""
echo "removeing directory usbbiosfiles..."
echo ""
rm -r ~/usbbiosfiles
exit
fi
modprobe loop && sleep 5 && check0="yes"
if [ "$check0" = "yes" ]
then
echo "Modprobeing loop... OK"
else
echo "Could not \modprobe loop"
echo "look above \for \info"
echo ""
echo "Reformat the USB Stick to FAT32 with gparted"
echo "Fix the problem and run this scrip agin"
echo ""
echo "removeing directory usbbiosfiles..."
echo ""
rm -r ~/usbbiosfiles
exit
fi
mount -o loop ~/usbbiosfiles/FDOEM.144 ~/usbbiosfiles/fdoem144 && check10="yes"
if [ "$check10" = "yes" ]
then
echo "Mounting FreeDOS on the fdoem144 directory... OK"
else
echo "Could not \mount FreeDOS on the fdoem144 directory"
echo "look above \for \info"
echo ""
echo "Reformat the USB Stick to FAT32 with gparted"
echo "Fix the problem and run this scrip agin"
echo ""
echo "removeing directory usbbiosfiles..."
echo ""
rm -r ~/usbbiosfiles
exit
fi
cp ~/usbbiosfiles/fdoem144/* $MOUNTX && check11="yes"
if [ "$check11" = "yes" ]
then
echo "Copying FreeDOS files to $MOUNTX... OK"
else
echo "Could not copy FreeDOS files to $MOUNTX"
echo "look above \for \info"
echo ""
echo "Reformat the USB Stick to FAT32 with gparted"
echo "Fix the problem and run this scrip agin"
echo ""
echo "removeing directory usbbiosfiles..."
echo ""
rm -r ~/usbbiosfiles
exit
fi
cp ~/usbbiosfiles/*.ROM $MOUNTX && check12="yes"
if [ "$check12" = "yes" ]
then
echo "Copying BIOS.ROM files to $MOUNTX... OK"
else
echo "Could not copy BIOS.ROM files to $MOUNTX"
echo "look above \for \info"
echo ""
echo "Reformat the USB Stick to FAT32 with gparted"
echo "Fix the problem and run this scrip agin"
echo ""
echo "removeing directory usbbiosfiles..."
echo ""
rm -r ~/usbbiosfiles
exit
fi
sync && check13="yes"
if [ "$check13" = "yes" ]
then
echo "Runing the syncing command... OK"
else
echo "Could not run the syncing command"
echo "look above \for \info"
echo ""
echo "Reformat the USB Stick to FAT32 with gparted"
echo "Fix the problem and run this scrip agin"
echo ""
echo "removeing directory usbbiosfiles..."
echo ""
rm -r ~/usbbiosfiles
exit
fi
umount ~/usbbiosfiles/fdoem144 && check14="yes"
if [ "$check14" = "yes" ]
then
echo "Unmounting of FreeDOS... OK"
else
echo "Could not unmount FreeDOS"
echo "Look above for errors or problems reported and fix the problem"
echo ""
echo "removeing directory usbbiosfiles..."
echo ""
echo "Reformat the USB Stick to FAT32 with gparted"
echo "Fix the problem and run this script agin"
rm -r ~/usbbiosfiles
exit
fi
verify="n"
while [ "$verify" != y ]
do
printf "Do you see any errors... yes or no?"
read AN2
echo ""
printf "You answered... $AN2 to errors. Is this correct... y or n?"
read verify
done
echo ""
if [ "$AN2" == "yes" ]
then
echo "User Repoted... Error"
echo "Look above for errors or problems reported and fix the problem"
echo ""
echo "removeing directory usbbiosfiles..."
echo ""
echo "Reformat the USB Stick to FAT32 with gparted"
echo "Fix the problem and run this script agin"
rm -r ~/usbbiosfiles
exit
else
echo "Success"
echo "I did a lot of error checking too and didnt find anything"
echo ""
echo "Go get a pen and paper to write down these instructions"
printf "Then hit the Enter to continue"
read WAIT
echo ""
echo "Now leave the USB Thumb Drive pluged into your computer and Reboot. When the Lenovo Logo POST screen appears hit F2 to enter the CMOS setup utility. Go over to BOOT tab and go down to HardDrive \(Not Boot Order) \then \select the USB Thumb Drive as the 1st hard drve. Then F10 and yes to save changes. Your compter will reboot agin. Then when the Lenovo Logo POST Screen appers on reboot hit F4 to enter the BIOS FLASHING program. The USB Thumb Drive will be seen as the C drive \in the list on the Left, Select it. Then \select the .ROM \file \in the list on the Right and start the BIOS FLASH. \(NOTE Your hart may stop beating... This is normal) Pray to any God you know of and your computer should restart just like normal. Hit F2 and the BIOS will now stay it is 06CN29WW. You will need to \set the boot order to the way you like it and other things \if you need to because they have been changed to the default."
fi
echo ""
echo "End of script"
Last edited by hunterthomson (2008-08-10 11:17:47)

Personally..... (this is just how I would have written it - if it works, then it's good enough for me though )
I would change this whole block:
verify="n"
while [ "$verify" != y ]
do
printf "Do you have mbr installed... yes or no?"
read AN1
echo ""
printf "You answered... $AN1 I have installed mbr. Is this correct... y or n?"
read verify
done
echo ""
if [ "$AN1" == "no" ]
then
echo "Install mbr now. Then run this script agin"
exit
else
echo "contunuing script"
fi
To this much shorter code:
MBR='/usr/bin/install-mbr' # Or where ever you expect it to be
if [ ! -x $MBR ] ; then
echo "mbr doesn't appear to be installed."
echo "If it is installed, check it's location, make sure it's executable and then make sure the MBR variable in this script is correct"
exit 1
fi
I wouldn't have used the checkXX variables for each stage:
mkdir ~/usbbiosfiles
if [ $? != 0 ] ; then
#failed
echo "Could not \make directory usbbiosfiles"
echo "look above \for \info"
echo "Fix the problem and run this scrip agin"
exit 1
else
echo "Made directory usbbiosfiles... OK"
fi
There is an issue with the way you do your verifications - the user can never get out unless they answer 'y' or hit CTRL+C. Something like this gives them options:
verify="n"
while [ "$verify" != "y" && "$verify" != "n" ]; do
echo "You need to answer 'y'es or 'n'o"
read verify
echo $verify | tr "[:upper:]" "[:lower:]" # This converts the answer to lowercase so replies entered in upper case will still work
done
if [ $verify != 'y' ] ; then
exit 1
fi
One last thing I try to do in scripts... Declare all your binaries as variables at the start of the program, then execute the binary program by using the variable. For example:
# Binaries
TAR='/bin/tar'
CP='/bin/cp'
CHMOD='/bin/chmod'
# Execute tar and chmod the created file
$TAR cvzf /tmp/tarfile.tar.gz /etc/*.conf
$CHMOD 400 /etc/*.conf
This way, it's easy to change the path in future without having to hunt through the script if the paths change, and it also ensures you're calling the programs using the full paths to make sure you're not executing some strange variant or alias that someone has setup. If I use `chmod` 30 times in a script, and the path changes in the future or on a different system (`chmod` is a bad example cause it's highly unlikely to change, but you know what I mean), then all you need to do is update the variable at the start of the script, and it all works again without having to script-hunt and change it 30 times.

[SOLVED]bash: assign a command output to a variable

EDIT: Sorry, got the solution - the variable was good, I just forgot a "do" in a "for" loop.... Sorry
Hi erveryone.
I'm just starting to learn the basics of bash scripting, and I got a problem assigning the output of a command to a variable, and i keep getting syntax errors...
var=$(cut -d: -f1 foo)
echo $var
A google search gives many different ways to do this, but without better results..
var=`cut -d: -f1 foo`
var="`cut -d: -f1 foo`"
Any idea what I'm doing wrong?
Thanks!
Last edited by haiku (2012-02-01 14:19:00)

haiku wrote:var=$(cut -d: -f1 foo)
var=`cut -d: -f1 foo`
The first two are both 'right' (in bash) but the first is the preferred syntax (in bash). I think sh only understands the second. I've never used quotes in a situation like this, but it seems to work. That said, maybe the problem is the command itself, because all variations work for me:
$ cat foo
genmon1a:genmon1b
genmon2:genmon3:genmon4
$ cut -d: -f1 foo
genmon1a
genmon2
$ D=$(cut -d: -f1 foo)
$ echo $D
genmon1a genmon2
$ D=`cut -d: -f1 foo`
$ echo $D
genmon1a genmon2
$ D="$(cut -d: -f1 foo)"
$ echo $D
genmon1a genmon2
$ D="`cut -d: -f1 foo`"
$ echo $D
genmon1a genmon2
It might help if you could give us some of the 'bigger picture' too: what you are trying to do overall, the contents of foo, what you are trying to do with the variable, etc.
Last edited by alphaniner (2012-02-01 14:31:01)

Solaris sends SIGKILL to bash script?

I have this bash script that just loops forever (until stopped), it outputs data to files and runs various other commands to display information on the terminal. The problem I'm having is that solaris seems to send SIGKILL to this script after it's been running for a period of time. Typically a few hours. As far as I can tell there's doesn't appear to be anything obviously wrong with the script. Why would solaris send a SIGKILL?? I know it's a sigkill from the exit code 137.
Anyone have any suggestions?? I'm running Solaris 8.
Thanks

No idea, it doesn't really make sense.
You could check if there is anything in crontab or similar which kills processes of idle users, but thats a bit of a long-shoot.
Make your script log to a file frequently, so you can figure out when to determine if its always around the same time, and in which part of the script.
If Solaris would send it a kill signal it wouldn't be SIGKILL.
.7/M.

Simple bash scripting help needed..

I want to learn som simple bash scripting in order to automate various tasks.. Im totally noob, so bear with me
First of all I would like to set configs without using nano.. is there a simple command for this? For example if i want change my hostname in /etc/rc.conf.. how can i print the current vallue and how can i change it`?
i was thinking something like this to get the current value:
# cat /etc/rc.conf | grep HOSTNAME=
which returns HOSTNAME="myhostname"
how can i change this value with one or more commands whitout touching the rest of the file?

abesto wrote:
A slightly naive solution:
CHOICE="lisa"
NAMES="homer marge lisa bart maggie"
if [ "`echo \" $NAMES \" | grep \" $CHOICE \"`" ]; then
echo "this is how you do it"
fi
The extra spaces inside the escaped quotes are to ensure that only a whole word is "matched".
You can also replace the elif's with a loop through a list of "the other variables". Then you'd use the loop variable instead of $CHOICE above.
grep can check on word-bounderies with \< and \>, or with the -w switch. The -q switch suppresses any messages and exits with exit-code 0 when the first match is found:
if echo "${NAMES}" | grep -qw "${CHOICE}"; then
Nice and readable, should work, but i haven't tested it
EDIT:
Procyon wrote:CHOICE="lisa"
NAMES="homer marge lisa bart maggie"
if [[ $NAMES =~ $CHOICE ]]; then echo match; fi
This one also matches elisa, ie. no check on word bounderies. You should be carefull with that
Last edited by klixon (2009-04-23 09:40:22)

[SOLVED] XMMS2 media hotkeys, bash scripts

Hi!
For the really beginners of the XMMS2 users as me, should be a nice something like a guide/tutorial.
Here is the bash scripts that might enchant functionality and be more useful for use of the media keys.
For randomizing before any other action you can use even something like:
xmms2 playlist shuffle ; xmms2 jump 1; xmms2 play
# Just for dummies
The Preview hotkey loop.
From the begin of the playlist to the end of it when current is the first one being played:
#!/bin/bash
#Play the previews or first if end of the playlist
if [ "XX"$(xmms2 prev | awk '{print $1}') == "XXServer" ] ; then
if [ "XX"$(xmms2 jump $(xmms2 list | grep -i '/' |wc -l) | awk '{print $1}') == "XXServer" ] ; then
xmms2 playlist list;
echo The playlist is empty, please choose one from of the above ;
echo or add a new songs to the playlist with a '"xmms2 add"';
fi; fi;
#It takes time to count to the last song in the playlist, longer it is more time it takes :(. I haven't found a better way yet.
The Next hotkey loop.
When the end of the playlist is reached then goto jumping to the first one song in the playlist:
#!/bin/bash
#Play the first song if in the end of the playlist
if [ "XX"$(xmms2 next | awk '{print $1}') == "XXServer" ] ; then
if [ "XX"$(xmms2 jump 1 | awk '{print $1}') == "XXServer" ] ; then
xmms2 playlist list;
echo The playlist is empty, please choose one from of the above ;
echo or add a new songs to the playlist with a '"xmms2 add"';
fi; fi;
For the Play/Pause key:
#!/bin/bash
#For the single Play/Pause key
GetStatus=$(xmms2 current | awk -F":" '{print $1}')
#Any command line parameters to the script for randomizing of the playslist.
if [ "S" != "S"$1 ] ; then
xmms2 playlist shuffle
fi;
if [ "$GetStatus" == "Playing" ]; then xmms2 pause;fi
if [ "$GetStatus" == "Paused" ]; then xmms2 play;fi
if [ "$GetStatus" == "Stopped" ]; then
xmms2 play
GetStatus=$(xmms2 current | awk -F":" '{print $1}')
if [ "$GetStatus" == "Stopped" ]; then
xmms2 playlist list;
echo The playlist is empty, please choose one from of the above ;
echo or add a new songs to the playlist with a '"xmms2 add"';
fi
fi
or you can use even xmms2 toggle command line for the play/pause hotkey.
Turn On/Off repeat/loop of the playlist:
#!/bin/bash
GetStatus=$(xmms2 server config playlist.repeat_all )
case $GetStatus in
"playlist.repeat_all = 1") xmms2 server config playlist.repeat_all 0 ; sudo beep; echo is OFF ;;
"playlist.repeat_all = 0") xmms2 server config playlist.repeat_all 1 ; sudo beep ; sudo beep ; echo is ON;;
esac
You can install beep but the beep has a problem, you can run it only as a root but a more danger way is to by pass this by adding the beep into /etc/sudoers , e.g. yourusername ALL=NOPASSWD: /usr/sbin/beep. Be careful! It may expose your system for unwanted access to and do a harm. The best way is to find a better way for notification of changes.
If someone has another script solutions for the multimedia hotkeys or media fun for XMMS2 then please share with us!
Automation is power of the shell
Notice
The hotkey names of my Digital Media Keyboard 3000, but I think that it becomes more as a standard, it is just to get a faster access to the names.
XF86AudioPlay, XF86AudioNext, XF86AudioPrev,XF86AudioStop
XF86AudioMute (amixer -c 0 set Master toggle), *, (pactl set-sink-mute 0 toggle)
XF86AudioRaiseVolume (amixer -c 0 set Master 3+), xmms2 server volume +3, (pactl set-sink-volume 0 +3%)
XF86AudioLowerVolume (amixer -c 0 set Master 3-). xmms2 server volume -3, (pactl set-sink-volume 0 -- -3%)
amixer = ALSA
pactl = PulseAudio (0 is index of the sinks, you can see which you can use with pacmd list-sinks, marked with * is default)
The other way to increase and decrease volumes is here.
Change between ALSA and PulseAudio sound servers for XMMS2
nyxmms2 server config output.plugin pulse
nyxmms2 server config output.plugin alsa
Otherwise you can use xev to retrieve the names of the supported keys by X server, as I know X server has a limitations to the 255 key numbers/keycodes. One more but less useful for GUI is showkey, just to know that it is also and always exists, with a great manual about the kbd keys.
* To mute/unmute XMMS2 you can use xmms2 server volume 0 / xmms2 server volume 100 or for more advanced e.g. xmms2 server volume -c left 100/xmms2 server volume -c right 100 and combine with any keys you wish the way is best for you. I haven't found any way to make anything to remember status after mute/unmute of xmms2. Alias for the mute only is xmms2 mute. If you will find it before me please help .
Here is one more guide for the BlackBox menu. I could not get xmms2 mlib loadall to work in Arch.
In Arch you must use xmms2 playlist sort instead of xmms2 sort because it doesn't work otherwise.
xmms2 playlist sort album
xmms2 playlist sort title
xmms2 playlist sort artis
Last edited by Andy_Crowd (2014-10-18 11:34:45)

Zariel wrote:
i guess something like this?
%optical ALL=(ALL) NOPASSWD: ALL
I found the clues for this in the sudoers manual:
handy ALL = NOPASSWD: /sbin/umount /CDROM,\
/sbin/mount -o nosuid\,nodev /dev/cd0a /CDROM
Which works in so far as now mounting no longer needs the password.
Which leaves me with the problem of trying to understand how to get Worker to mount the optical drive on command.
If I enter the bash command in the Terminal as follows:
mount /mnt/dvd
the media is mounted, after which I can push the button in Worker, which I have configured with:
/mnt/dvd
& the root list of the optical media is displayed in the active panel of Worker.
I just haven't been able to get Worker to use "mount /mnt/dvd" yet, there will be a way, I wonder how long it will take me to find it? lol
Last edited by handy (2008-11-19 06:48:09)

Sending email using bash script

Hello:
I am working on writing a bash script to notify one or more users by email of certain events. Run from the Terminal command line, and having the script "echo" text of (what would be) a form letter with in-line variable expansion (i.e., ${VARIABLE}), all seems to work as anticipated. Eventually, I want cron to launch this shell script, and send an email to an "on-subnet" user (I have postfix enabled on my Mac, and there are multiple local user accounts).
I found some stuff on the web about sending mail from bash scripts, and so I made a small little test script, that reads like this:
#!/bin/bash
VARIABLE[1]="The 12,345 quick brown foxes "
VARIABLE[2]="jumped over the 67,890 lazy dogs."
mail -s "a test email" jv << EOF
This is a test:
${VARIABLE[1]}
${VARIABLE[2]}
This is the last line of the test message.
EOF
echo "script completed"
It worked... almost... It sent a local email to my postfix mail account that read like this:
This is a test:
The 12,345 quick brown foxes
jumped over the 67,890 lazy dogs.
This is the last line of the test message.
EOF
echo "script completed"
So, I have two questions. First, the easy one (I hope):
How do I delimit the end of the text, that I want to be the message body of the email, from portions of the script that follow said email text?
Next question is a little more involved. You know how, in Mail.app, if you go to Mail Preferences>Accounts>Account Information, you can put multiple email addresses, comma-delimited, in the "Email Address" field? So, if a person entered "[email protected], [email protected], [email protected]" in this field, then, even though (s)he may be at home, and using their home ISP's mail server, (s)he could send an email apparently from either their home, work, or school email address. Of course, the mail headers clearly would show it came from and through their home machine and home ISP, but it would be displayed in the recipient's Mail client viewer as having come from one of [email protected], [email protected], or [email protected].
I'd like to do something similar here, whereby the email (that is being sent to one or more local users' postfix account on my computer) would apparently be sent from "watchdog@localhost" rather than from "jv@localhost" like it seems to do by default. Whatever account the script is run from (or presumbably, whose cron tab is launching the script) is what the "From" address is set to.
I'd rather not create an additional mail account, because I am using Mac OS X built-in accounts for the postfix mailboxes (I don't want to have to maintain a plaintext username:password file in postfix, and I don't want to create an additional user account on the computer).
So, is there a way to specify an alternate "From" username when invoking the mail -s ${SUBJECT} ${RECIPIENT} command in a bash script? Or is there a different, alternate mail command that will let me do so? (please include a description of syntax and how I'd package the above message text for the alternate method).
Thanks in advance, all!

Hi j.v.,
The > after EOF is just a typo (or may be added by the Discussion ?) and you must delete it; other > are prompts from the interactive shell. Andy's post shows an interactive use of shell, not a shell script (note the shell prompt % in front of the commands). A typical use of here document may look like
command <<ENDOFDATA
ENDOFDATA
There must be no spaces before and after ENDOFDATA. The word ENDOFDATA can be EOF or any other string which is guaranteed not to appear in the text (the .... in the example above).
You can modify the From: header by using sendmail command (postfix has it as a compatibility interface):
/usr/sbin/sendmail -t <<EndOfMessage
Subject: test mail
To: jv
From: watchdog
This is a test:
${VARIABLE[1]}
${VARIABLE[2]}
This is the last line of the test message.
EndOfMessage
There must be a blank line between the headers and the mail body.
I assume that you send these mails only to users on your local Mac. Please do not send mails to remote users by using the sendmail command unless you know what you are doing completely.
PowerMac G4 Mac OS X (10.4.5)

Using Bash script to edit config file

This is a really simple question, but given that I'm just learning Bash scripting and having this solved now would be really illustrative for me, I would really thank some help here.
I'm using uzbl, and running Tor+Polipo. So, as you will see below in the tail of the config file, there is a line to redirect the requests of uzbl through Polipo.
# === Post-load misc commands ================================================
sync_spawn_exec @scripts_dir/load_cookies.sh
sync_spawn_exec @scripts_dir/load_cookies.sh @data_home/uzbl/session-cookies.txt
# Set the "home" page.
#set uri = https://duckduckgo.com
# Local polipo proxy
set proxy_url = http://127.0.0.1:8123
# vim: set fdm=syntax:
What I want to accomplish is to comment in/out that line with a key shortcut on Awesome. I've thought of doing 2 scripts to do so and using 2 differente key shortcuts, but I want to "toggle" the proxy redirection with only 1 shortcut. To do so, I suppose that the script should go something like:
if
tool 'set proxy_url = http://127.0.0.1:8123' config_file
then
tool '#set proxy_url = http://127.0.0.1:8123' config_file
else
if
tool '#set proxy_url = http://127.0.0.1:8123' config_file
then
tool 'set proxy_url = http://127.0.0.1:8123' config_file
fi
fi
I know little about sed, but I think is the tool for this job. The most intriging part to me is to ask sed to print the regular expression when it finds it in the config file, and use that as an input in the conditional statement.
Well, this is a mess I have done here. Hope there is a simple answer to this.
Thanks in advance.-

You can do this with a single sed command:
sed -i 's/^#set proxy_url/set proxy_url/;
t end;
s/^set proxy_url/#set proxy_url/;
: end' config_file
This edits the file in-place (-i) and first tries to replace the commented with the uncommented line. If that suceeds, sed jumps to the "end" label. If not, it tries to replace the uncommented with the commented line. Thus you don't have to include any logic about the current state: if the first substitution succeeds, the line was obviously commented, if not, it was uncommented, and the second substitution should succeed.
Note that my knowledge of sed is very limited. There might be a simpler way to do this.
EDIT: For the sake of example, here's how to do the same in bash using regular expressions. Note how this script needs to use a temporary file to simulate in-place editing, how it needs to process the file line by line manually, etc. All things that sed does out of the box...
#!/bin/bash
tmp=test.conf.tmp
echo -n "" > "$tmp"
while read line; do
if [[ "$line" =~ ^#set\ proxy ]]; then
echo "${line/\#/}" >> "$tmp"
elif [[ "$line" =~ ^set\ proxy ]]; then
echo "#$line" >> "$tmp"
else
echo "$line" >> "$tmp"
fi
done < test.conf
mv test.conf.tmp test.conf
To answer your original question, the line
if [[ "$line" =~ ^#set\ proxy ]]; then
reads: if the line begins with a "#", followed by "set proxy", then...
Last edited by hbekel (2011-03-20 10:40:16)

HOW DO I RUN A UNIX BASH SCRIPT FROM JAVA??

HI. Here's a tricky little problem i have. There's a unix bash script that has some commands in it, that manipulate a file. It appends a certain string variable to a file called users. The users file is an ordinary text file.
I know this script to work perfectly, when i invoke it like this directyl from the command line: ./addusers.sh
or even: bash /downloads/selinux/policy/addusers.sh
Now, i have a java program, and its meant to just execute that script. It doesnt throw any Exceptions at runtime. But when i look at the users file, and expect it to have an extra line that was the string variable, the file is UNTOUCHED!
Again, direct command line invocation works, but not from java. Here's what my invocation from java looks like:
Process p = Runtime.getRunTime().exec("bash downloads/selinux/policy/addusers.sh");
The strange thing is, i tried a different bash command. I tried:
Process p = Runtime.getRunTime().exec("mkdir /temporary");
and this worked!
so why not the other one??
I cant figure it out.

You say:
bash /downloads/selinux/policy/addusers.sh
And you say in Java:
Process p = Runtime.getRunTime().exec("bash
downloads/selinux/policy/addusers.sh");
As if a leading / would be missing from the Java
version...nyix says:>
...OK sorry about that. i DO have a / in front of the downloads.... section in the java method. So its:
Process p = Runtime.getRunTime().
exec("bash /downloads/selinux/policy/addusers.sh");
HELP please?

How can I execute a bash script by double clicking in finder

Hello!
How can I execute a bash script using finder? Or better: How can I create an alias, which executes my bash script?
Thanks Johann

Add the suffix command in your script name. E.g. Script.command.

Bash script: Loop command,

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