Linux commands collection

Terminal commands for general information

• Check os version in Linux
  cat /etc/os-release
• Find Linux kernel version
  uname -r

Terminal commands for simple tasks

• To make files like .bin file into executable.
  chmod +x filename.extention
  Then you can run it using ./filename.bin

Solutions

Ubuntu update error: "waiting for unattended-upgr to exit"

1. Stop the automatic updater
   sudo dpkg-reconfigure -plow unattended-upgrades
   At the first prompt, choose not to download and install updates.
   Do a reboot.
2. Make sure any packages in an unclean state are installed correctly.
   sudo dpkg --configure -a
3. Get your system up-top-date.
   sudo apt update && sudo apt -f install && sudo apt full-upgrade
4. Turn the automatic updater back on, now that the blockage is cleared.
   sudo dpkg-reconfigure -plow unattended-upgrades
   Select the package unattended-upgrades again.
   Source

Ubuntu Software: Unable to install "PACKAGE": snap "PACKAGE" has "install-snap" change in progress

Snap is probably still working on something in the background (or at least it thinks so). Open a terminal and run snap changes so see a list of ongoing changes.

$ snap changes
ID   Status  Spawn               Ready  Summary
...
110  Doing   today at 13:09 IST  -      Install "code" snap from "latest/stable" channel
...

You can abort ongoing change(s):

sudo snap abort 110

Then you should be able to successfully install the package through the software center, or through the command line using snap install PACKAGE_NAME.
Source

Tips and Tricks

Tell GRUB to reboot into Windows only for the next reboot

In a dual boot system, if you want to reboot to Windows from Ubuntu terminal just once instead of permanently altering the boot order, do the following steps:

1. Edit the /etc/default/grub and replace GRUB_DEFAULT=0 with GRUB_DEFAULT=saved

2. sudo update-grub

3. Your command for one time reboot to Windows will be:

   sudo grub-reboot "$(grep -i windows /boot/grub/grub.cfg|cut -d"'" -f2)" && sudo reboot

To make it a function that can be called to do the same: Edit ~/.bashrc using any editor and add the following lines at the bottom and source it:

# Reboot directly to Windows
# Inspired by http://askubuntu.com/questions/18170/how-to-reboot-into-windows-from-ubuntu
reboot_to_windows ()
{
    windows_title=$(grep -i windows /boot/grub/grub.cfg | cut -d "'" -f 2)
    sudo grub-reboot "$windows_title" && sudo reboot
}
alias reboot-to-windows='reboot_to_windows'

Now you can reboot to Windows one time by typing reboot-to-windows on a terminal.

In case, your grub.conf contains multiple lines for Windows, following functions will take care only about lines starting by menuentry and picking just the first one, referring to Windows:

function my_reboot_to_windows {
    WINDOWS_TITLE=`grep -i "^menuentry 'Windows" /boot/grub/grub.cfg|head -n 1|cut -d"'" -f2`
    sudo grub-reboot "$WINDOWS_TITLE"
    sudo reboot
}

Source