Sometimes Nautilus' icon thumbnails and/or metadata for a file, photo, or folder just aren't good enough to make sure it's the desired file.
Is there an app for Ubuntu similar to Mac OSX's "Quick Look" feature in order to get a closer look without opening the file?
I encountered the following error while upgrading my Ubuntu 12.04 server. Now apt-get is unable to install or removed any package.
Unpacking linux-headers-3.13.0-62 (from .../linux-headers-3.13.0-62_3.13.0-62.102~precise1_all.deb) ... dpkg: error processing /var/cache/apt/archives/linux-headers-3.13.0-62_3.13.0-62.102~precise1_all.deb (--unpack): unable to create `/usr/src/linux-headers-3.13.0-62/arch/arm/include/asm/ptrace.h.dpkg-new' (while processing `./usr/src/linux-headers-3.13.0-62/arch/arm/include/asm/ptrace.h'): No space left on device No apport report written because the error message indicates a disk full error dpkg-deb: error: subprocess paste was killed by signal (Broken pipe) Errors were encountered while processing: /var/cache/apt/archives/linux-headers-3.13.0-62_3.13.0-62.102~precise1_all.deb E: Sub-process /usr/bin/dpkg returned an error code (1)
Though I am not really out of disk space,
# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda1 6.8G 4.7G 1.8G 69% /
Anyhow my inodes are full,
# df -i
Filesystem Inodes IUsed IFree IUse% Mounted on
/dev/sda1 458752 455214 3538 100% /
I have more than ten old kernels but I am unable to remove those as my apt-get itself is lame. So I am unable to follow this post which reports similar problem.
The only option seems to delete a few older kernels manually. Will it cause any problem?
Is there any better way out? Can I use reserved space for root for the time being and remove older kernels?
I was looking at iptables man pages. But I did not find anything about --sport and --dport.
--sport is short for --source-port
--dport is short for --destination-port
Why are those options missing from Ubuntu manpages? I also looked at
iptables --help
info iptables
I was generating random characters for some purpose. By mistake I try the following in a terminal and got some surprising result. I am using bash shell provided by Ubuntu.
$ echo {Z..a}
Z [ ] ^ _ ` a
Inspiring by this result, I did
$ echo {z..A}
z y x w v u t s r q p o n m l k j i h g f e d c b a ` _ ^ ] [ Z Y X W V U T S R Q P O N M L K J I H G F E D C B A
My question is what are these five characters [ ] ^ _ ` doing in the range. Do they have any special meaning or I am just performing some forbidden action.
People usually use $ echo {{A..Z},{a..z}} in order to get both lower as well as the upper case characters,
I have two Dropbox accounts. Is it possible to link and use both of the accounts simultaneously without logging in as the different user?
Do not confuse with similar looking post
Multiple Dropbox accounts on the same computer for different users.
I can check md5sum hash of a file from a terminal as,
$ md5sum my_sensitive_file
8dad53cfc973c59864b8318263737462 my_sensitive_file
But the difficult part is to compare the hash value with exact one.
It is difficult to compare the 32 characters output with original/exact hash value by any human for a large numbers of files. First of all the job would be very monotonous and there are big scope of errors.
Is it possible to automate the comparing process, preferably in CLI?
Sometimes while going to open a file from Nautilus I do not find the intended application in "open with" menu on right click. Or the desired application remains hidden in a long list of applications. It becomes difficult to find it quickly.
Prior to Ubuntu 11.04 there was a nice feature "Use a custom command" under "open with" menu on right click on a file. One could able write a command in the box to open a file with a custom application. This option is no longer available in Nautilus after Ubuntu 10.10.
Question:
Can I have a similar "Use a custom command" dialogue box on Nautilus so that I can open a file writing any custom command in a box as shown in the above picture?
Need some clarification about the permissions of .desktop files. I can see all the .desktop files in /usr/share/applications/ owned by root have permission,
-rw-r--r--
also examples.desktop at $HOME owned by user has the same permission. All of those run properly.
But when I am going to create a custom .desktop file having the same permission it is throwing the following error message,
Untrusted application launcher
The application launcher "myapp.desktop" has not been marked as trusted. If you do not know the source of this file, launching it may be unsafe.
But adding the execution permission is allowing it to run without any issue.
Q: Why custom
.desktopfiles need to have+xpermissions to run or how some.desktopfiles can run without execution permission? Is it possible to run a custom.desktopfile without execution permission?
The reasons why a cron job may fail is really very large. Most common reasons may be,
- Syntax error
- Using executable without proper path
- Using a shell variable which is not defined in cron environment
- Attempt to open a GUI without specifying
DISPLAYAnd so on...
Sometimes it is really difficult to understand which error is preventing the job to be executed. Is there a way to detect error(s) in a cron jobs?
I can see there are many lock file here and there in my system. What is the exact role and purpose of those lock files?
In my system I got this list,
/run/lock/whoopsie/lock
/proc/sys/dev/cdrom/lock
/var/lib/dpkg/lock
/var/lib/apt/lists/lock
/var/cache/apt/archives/lock
How do I install different desktop managers like Unity, KDE, XFCE etc in different ttys so that I could toggle them using CtrlAlt+F N, where N is 4,5,6 etc. In this answer I got the hint of such possibility. But I could not found a good documentation of the same.
Many times I got warning/notice while accidentally tried to do some privileged action using my non-root account like below,
gulu@workpc:~$ sudo apt-get update
[sudo] password for gulu:
gulu is not in the sudoers file. This incident will be reported.
But when I logged into my sudoers account I never received any report of such an incident. Where are the reports reported?
How to access those? Or is it some trivial Warning message for non-sudoers?
I made this simple script to copy a file recursively to many sub-directories. Here I am showing the problem for 3 sub-directories. I have 3 sub-directories and 2 files in a directory as follows
0.003/ 0.007/ 0.015/ program.cpp driver.sh*
I want to copy program.cpp to all these sub-directories using myscript.sh shown below:
#!/bin/bash
mydir=`pwd`
for i in `ls -la $mydir | grep "[0-9]$" | awk '{print $NF}'`
do
if [ -e $mydir/$1 ]
then
echo "cp -i $1 $i/"
else
echo "File \"$1\" not found in current directory"
fi
done
I have put the cp inside echo to test the code. The output is strange,
cp -i program.cpp 32/
cp -i program.cpp 0.003/
cp -i program.cpp 0.007/
cp -i program.cpp 0.015/
The output of ls -la
total 32K
drwxr-xr-x. 5 gulu workg 4.0K Nov 29 2013 .
drwxr-xr-x. 7 gulu workg 4.0K Nov 29 2013 ..
drwxr-xr-x. 2 gulu workg 4.0K Nov 26 19:09 0.003
drwxr-xr-x. 2 gulu workg 4.0K Nov 26 19:09 0.007
drwxr-xr-x. 2 gulu workg 4.0K Nov 26 19:09 0.015
-rw-r--r--. 1 gulu workg 4.2K Nov 29 2013 program.cpp
-rwxr-xr-x. 1 gulu workg 982 Nov 26 08:22 driver.sh
The output of ls -la $mydir | grep "[0-9]$" | awk '{print $NF}'
0.003
0.007
0.015
There are only three values in i then how is it producing four output? Anyway I have solved the problem with an additional condition [ -d $mydir/$i ]. But my question is how the script is producing the first line cp -i driver.sh 32/?
I have installed python-pygments and using it for syntax highlighting with less as described by mankoff here
I put a function in my .bashrc
cless () {
pygmentize -f terminal "$1" | less -R
}
it is enabling syntax highlighting with less. But when I am going to open a file like /etc/fstab or /etc/apt/apt.conf a error saying
Error: no lexer for filename '/etc/apt/apt.conf' found
I found option to show pygmentize the lexer with -l at this manpage. But what will be the appropriate lexer for such files? and how to use it?
When I am trying to open any video file [ .mp4, .mkv, .flv so far ] with mplayer from right click context menu on Nautilus, the following things are happening:
mplayer is freezing. To stop it I had to kill it. If I run those same videos with mplayer from a terminal everything is fine without any issue. Only the control box is not there (I think this is default, I don't have an issue with it).
I am going to install Ubuntu on an UEFI system (dual boot with Windows) where
I need to install boot-repair. When I run sudo apt-get update it will
update cache for all the repos. I need to update only a particular ppa
(yannubuntu/boot- repair) to install boot-repair.
Many times I had to update all the repos when I think updating a single ppa is enough.
No then how could I update a particular repo?
In Ubuntu 12.04 Nautilus is not showing preview thumbnails for .agr files produced by Grace unlike Ubuntu 10.04. How can I have preview thumbnails for .agr files on Ubuntu 12.04.
sample file. https://www.dropbox.com/s/tfb0z8xfg7p4nvq/sample.agr
Is it possible to write a shell script that enables any user (may not be root) to set a message(e.g. "Download on progress do not turn off" etc.) which will be conveyed like pop-up message (zenity or notify-send) to all other users. If any user is not there at the time of throwing the message they must get it on login or unlocking their screen.
Is there a way to carry audio over ssh?
Say after connecting to remote machine through ssh -X I opened a browser and want to watch a youtube video. Currently I could only able to watch the video without any audio. But I want to hear the audio too. How to do that?
While I am trying to connect to a remote system from terminal using sftp
sftp [email protected]
connection is failing and a message coming
Received message too long < some long number >
I connect that machine frequently, can not understand what is causing the problem.