Melab's questions

I am on Ubuntu 20.04. My GNOME Shell is at version 3.36.4. I am using GNOME Tweaks to show files on the desktop.

An example of what works: In Terminal, I type cp /usr/share/applications/org.gnome.Terminal.org ~/Desktop. On the desktop (NOT from Nautilus), I right-click the icon of a gear on a paper sheet with the caption org.gnome.Terminal.… and there is Allow Launching. I click that menu entry and the icon is changed to Terminal's icon and the caption now says Terminal.

What doesn't work: I create a file under ~/Desktop with the name Reboot-into-Text-Mode.desktop. I edit the file so that it reads

[Desktop]
Name=Reboot into Text Mode
Exec=pkexec /opt/scripts/kexec-text

From Terminal, I run chmod +x ~/Desktop/Reboot-into-Text-Mode.desktop. When I right click the corresponding icon on the desktop (NOT from Nautilus), I am given a context menu that does NOT contain Allow Launching`. I want to be able to run this command by clicking a desktop shortcut and not just from the terminal.

How can I make my .desktop file launchable? Why can't I make it launchable when I was able to make Terminal's .desktop file launchable?

Installing LXD from APT installs it as a Snap package and while LXC programs are installed from a Debian package, running them tells me I need to install the LXD snap. Is there anyway to install LXC and LXD as a Debian package? Is LXD supposed to supersede LXC?

My main account on my Ubuntu 15.10 has a password that does NOT meet the system's default password requirements. It is this way because either:

• setting the password on installation doesn't run into any restrictions.
• it was set during an earlier version which did not have such restrictions.

I have created a test user through the GUI and I am trying to set the password to test. It will not accept it. Other answers on this site say that I need to change the twenty-fifth line in /etc/pam.d/common-password from

password        [success=1 default=ignore]      pam_unix.so obscure sha512

to

password        [success=1 default=ignore]      pam_unix.so minlen=1 sha512

I did that, but the GUI still will not let me set my test user's password to test. Please tell me how to remove these password restrictions.

I am running Ubuntu 15.10 in VMware Workstation 12 Player on Windows 7. Since VMware has stopped updating VMware Tools or something, I have to use open-vm-tools. Unfortunately, it doesn't resize the display. My installation is something of a mess because I've been toying around with the GitHub release, had some problems removing VMware Tools resulting in a partial install, and installed from source code meaning I can't likewise uninstall.

How can I get open-vm-tools to work and properly resize the display?

I accidentally deleted ~/Desktop. This directory plays some kind of important role because now that it is gone all of the folders under ~/ are showing up on my accounts desktop. How do I fix this?

Installing Xen on a host machine is easy, but installing an operating system inside a Xen virtual machine is poorly documented. Assume that the system I wish to setup:

• uses paravirtualization.
• uses an image file instead of LVM.
• has the kernel and initial RAM disk residing on the host machine instead of in the virtual machine image.

Where do I get the appropriate kernel and initial RAM disk files? How do I install the operating system in the virtual machine?

I am running an instance of Ubuntu 15.10. I need to install the latest kernel used by Ubuntu 14.10, which I think is 3.16.0-28-generic. Entering sudo apt-get install linux-image-3.16.0-28-generic returns an error message stating that it's not available and may have been obsoleted or whatever. I think if I add something to sources.list it will be able to get it. But what do I add to it?

And before anyone goes on about the troubles this may produce, it doesn't matter to me.

I have two partitions and one is meant to be solely for GRUB2's files. The layout of the filesystem on the first partition should look like:

/
     fonts/
     i386-pc/
     locale/
     grub.cfg
     grubenv

This is what I expect to get when I run grub-install --boot-directory=/mnt /dev/sda. Instead, I get this:

/
    grub/
        fonts/
        i386-pc/
        locale/
        grub.cfg
        grubenv

Why is it placing them in another sub-directory? I did not specify /mnt/grub and I have seen GRUB get installed to folders like /boot/grub2, so I know that it doesn't always make a folder named grub. How do I force it to do what I want it to do?

sudo modprobe loop max_loop=255 does not return an error, but lsmod | grep "loop" returns nothing. Likewise find /lib/modules/$(uname -r) -name "loop.ko" doesn't print any paths to the screen.

I'd think that this was because it was missing, but if I use modprobe to load a nonsense name, then I get an error that it doesn't exist.

So, where is the kernel module loop? Does it exist at all?

I recently installed the Debian packages produced by running make deb-pkg to compile my own version of the Ubuntu kernel. I had given the kernel the release version 3.19.0-21-secure. All of the packages were installed with that in their names except one: linux-libc-dev. It appears that there is no version information that identifies that packages, meaning that my installation of my locally built linux-libc-dev package probably overwrote the official one.

I am hesitant about removing it because apt-get will remove all the packages that depend on it without asking me. I tried running sudo apt-get install --reinstall linux-libc-dev and I got this error:

Reinstallation of linux-libc-dev is not possible, it cannot be downloaded.

I tried to see if apt-get can locate the official version at all using sudo apt-get download linux-libc-dev and I got:

E: Can't find a source to download version '3.19.0-21-secure-3' of 'linux-libc-dev:amd64'

Aptitude thinks that it's getting the correct package, but it isn't. How can I fix this?

On Ubuntu, the string returned by uname -r is always of the form x.y.0-z-generic (i.e., 3.19.0-21-generic). Compiling Ubuntu's kernel ends up with a string that is of the form x.y.z (i.e., 3.19.8), the actual version of the kernel that is used. What does the z represent in the first case? Is that the EXTRAVERSION parameter or is it something else? How do I get the version string of my build of Ubuntu to match the official one?

I'm working in a command line-only environment, so I'm used to redirecting output to text files. In this instance, I need to set a password for GRUB2, but trying to use redirection with the corresponding utility makes it stop printing to the screen, so I am not presented with a way to enter my desired password. How do I solve this?

I'm running Ubuntu 14.10 in VMware Player on Windows 7. I have installed open-vm-tools instead of VMware Tools because VMware's software was unable to compile the kernel module required for file sharing. I cannot get my shared folder to mount with sudo mount -t vmhgfs .host:/$(vmware-hgfsclient) /mnt/hgfs or sudo vmware-hgfsmounter .host:/$(vmware-hgfsclient) /mnt/hgfs. Both return Error: cannot canonicalize mount point: No such file or directory. I have no idea what this is referring to or how to fix it.

A computer's master boot record consists of raw binary and does not reside on any sort of partition. Legacy GRUB and GRUB 2 are installed to the sectors inbetween the end of the MBR and the start of the first partition. The boot code in the MBR, which is blind to filesystem formatting, loads GRUB from the no man's land residing after it. Why are the MBR (boot.img) and GRUB (core.img) accessible as files through the Linux filesystem?

This whole deal with jails and chroot is a bit confusing to me. They are used to run possibly risky programs securely, but this has to be initiated by the user. I'm looking for how to jail users like how Android and iOS do it. This can be setup for remote logins, but how can this be set for home logins?

Assume that I have Ubuntu installed on a desktop PC. There are four users: administrator, user1, user2, and guest. The first logs in like an account normally does. The second and third login to a jail. The fourth logs into a more restrictive jail than the second and third. Do these jailed accounts have access to a virtualized environment of sorts? Do these include copies of core binaries or are they built into the all's interface? Are these accomplished with initialization scripts or something else?

I've recently noticed that GRUB is capable of performing signature checks and software-based secure boot operations. I wanted to give it a try, so I followed the instructions here and executed sudo grub-install --pubkey=<my-key> /dev/sda. The only problem is that even though I properly signed all of GRUB's modules, it is incapable of loading them, including the ones necessary for performing signature checks in the first place. While verify_detached is built into GRUB, I get an error telling me that the hash function for SHA-256 isn't loaded. Does anyone know what I'm doing wrong here?

I'm looking for the way to build GRUB2 from scratch. I'm not using grub-mkimage or anything like that. I downloaded the source code with apt-get source grub2 and unzipped the Debian tarball. Inside the folder there is configure tool or autogen file. make asks me to specify a build target. Can anyone tell me how to begin with this?

I am running Ubuntu 12.04. In my accounts .bashrc file I have the line

alias ftreport='cd / && sudo tree > /home/<user name here>/Documents/Reports/Tree_$(date +%s).txt'

After typing the command ftreport, I get

bash: /home/<user name here>/Documents/Reports/Tree_<epoc time here>.txt: No such file or directory

The command ftreport must output my system's file tree in my ~/Documents/Reports folder with the file title consisting of "File", an underscore, the epoch time, and ".txt". What is wrong and what should it be?

I am running Ubuntu 12.04 and I am trying to compile the cpabe toolkit, but first I have to compile libbswabe. However, when I try to build libbswabe-0.9 it gives me an error stating that glib.h cannot be found. Here is the relevant text from the config.log file:

configure:4013: checking for GLIB - version >= 2.0.0
configure:4145: result: no
configure:4173: gcc -o conftest -O3 -Wall   -O3 -Wall conftest.c -lcrypto   >&5
conftest.c:31:18: fatal error: glib.h: No such file or directory
compilation terminated.

What is glib.h and how do I install it? And I did successfully enter sudo apt-get install libglib2.0-dev into the command line.

Here are my circumstances:

• I am running Ubuntu 12.04.
• I have one user account.

I absolutely hate the password requirement. How do I disable this requirement such that my Linux computer will behave more like Windows in this respect? I do not want to hear that I shouldn't this because it is not secure. This is my desire so the concern of security is effectively null and void.