Choosing between /dev/sda and /dev/sdb for boot loader installation

I am a Windows 10 user and I would like to try Ubuntu 18.04.3 LTS. I use Windows 10 to my 595 GB disk 0 (C:) and I wish to install Ubuntu on my empty 595 GB disk 1 (D:). My aim is to select which operating system to use on every startup. Therefore, I shrunk disk disk 1 (D:) and created an unallocated 200.20 GB partition in order to install there Ubuntu. I booted into Ubuntu using a USB Ubuntu bootable drive. In the partitions table, I clicked the 214 gb free space, and chose the following partitions for installation (I haven’t made any change yet or proceed to the installation).

/dev/sda   TYPE        SIZE    USED    SYSTEM /dev/sda1  ntfs       209 MB   42 MB  Windows 10 /dev/sda2  ntfs       424 GB  108 MB /dev/sda5  swap         9 GB /dev/sda6  ext4/       20 GB /dev/sda7  ext4/home  185 GB  /dev/sdb /dev/sdb1  ntfs       639 GB  581 GB  /dev/sdb2  ntfs       300 GB  448 MB 

You can see that I partitioned the free space to /dev/sda5, /dev/sda6 and /dev/sda7.


  1. How can I know which drives are /dev/sda and /deb/sdb? Since Windows 7 is installed on disk 0 (C:) and having used already 543 GB there, while disk 1 (D:) is empty, I suppose that /dev/sdb is disk 0 (C:) and that /dev/sda is disk disk 1 (D:). Is that correct? Furthermore, as the free space which was in disk 1 (D:) became /dev/sda5, /dev/sda6 and /dev/sda7, I assume again that disk 1 (D:) is /dev/sda. Are my thoughts correct?
  2. a) May someone explain to me what is the device for boot loader installation? Do I already have such a device? If so, how can I find which it is?

    b) I must choose to select either /dev/sda or /dev/sdb. The installer defaulted to dev/sda. Does it matter which I choose? Will a wrong choice affect my windows installation or files on disk 0 (C:)? Is it possible that I won’t be able to boot on Windows 10 if I choose wrong?

  3. In the worst case that something goes wrong with the boot loader installation, can I fix that problem booting from my USB bootable drive or I will have to reinstall Windows 10?

Note: There are similar questions here and here. The first link troubles me, the second link doesn’t give details for the boot loader installation, and both links don’t answer all my questions.

Thank you in advance for any help!

How can i tell the difference between fishing for rolls and being involved?

I have recently started playing BW and i decided to go in a new direction(Mainly because i couldn’t make a druid.) and made a charlatan with some bard sprinkled in. A noble woman in her early twenties that were to receive formal education at a religious institude but bailed out after learning superficial knowledge about pretty much everything and she has been using those skills to be a jack of all trades that seems like she knows a lot but only has enough to fake it.

With that i thought i would play her as someone that will try to help with everything. Someone wounded?I’ll help. Need to interpret stars?I’ll help and so on. My problem is that with such a diverse skillset in the first session i ended up asking to roll for things far more than other players coming up with a bunch of stuff i wanted to try.

My problem is that I fear that i may advance quicker than others and end up being a munchkin or something similar. So what i wanted to ask was that how can i play my character as someone who tries everything without turning her into a munchkin that can do everything better than everyone else?

Is Python’s Grammar in a known Category between CFG and CSG?

I have a high level understanding of formal languages and grammars, and I’m familiar with the four major types of grammars in Chomsky hierarchy. I was interested in knowing the classification of Python’s grammar. A quick search yielded some quick, but incomplete answers.

I’ve heard of context-free grammars (CFGs), but are context-sensitive grammars used in any applications? from compsci

Is Python a context-free language?

The immediate takeaway from most resources it that Python’s grammar is not a context free grammar (CFG). But that doesn’t answer the question of what it is. Looking deeper I found that its a complete context sensitive grammar (CSG) either. But still no classification.

At this point the conclusion was that there must exist classes of grammars between CFGs and CSGs, but I had never heard anything about these.

What I do understand is Python’s lexer (which transforms character sequences into tokens) does something that a CFG cannot do: it tracks the level of indentation and yields special INDENT DEDENT tokens. After this transformation resulting tokens are context-free and can be parsed into an abstract syntax tree. Thus the grammar on tokens is a CFG, but the grammar on characters uses slightly power power than a CFG can provide alone. I want to know if there is a classification for this type of grammar. What is between a CFG and a CSG?

After a bit more searching I stumbled on this table at the bottom of a Wikpedia article:

Here is an image of that table:

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Cool, I found that there are known grammars between CFG and CSGs. But I’m not an expert on formal languages, so I don’t know how I would go about determining which if any of these categories Python’s grammar belonged to.

Is it a “Positive range concatenation”, “Indexed”, “Thread automation’s Grammar”, “Linear context-free rewriting system”, “Tree-adjoining”? Is it none of these; if so does what it is have a classification?

Note: The full grammar specification of Python 3 can be found here:

How to check if a connection between a server and an app is encrypted?

I have a Corona SDK sample project that contains only the following code:

-- The following sample code contacts Google's encrypted search over SSL -- and prints the response (in this case, the HTML source of the home page) -- to the Corona terminal.  local function networkListener( event )      if ( event.isError ) then         print( "Network error: ", event.response )     else         print ( "RESPONSE: " .. event.response )     end end  -- Access Google over SSL: network.request( "", "GET", networkListener ) 

The code has been copied directly from Corona SDK’s documentation.

Once the network request completes, the console will output the requested HTML source. However, my question is, how can I verify that the network request and all information that was exchanged was actually encrypted and not clearly legible as it is in the console output?

I am planning on creating an app that will communicate with a PHP file on my server over SSL and being able to verify that the traffic between the server and the Corona made app is actually encrypted is essential since I’d be sending over passwords and other confidential (but not personally identifiable) information.

Mouse movement between screens with different screen resolution

I’m looking for a way to resolve the scaling issues between different resolution monitors and moving the mouse between them.

When moving the mouse to the edge of the screen, it hits an invisible void instead of moving onto the next screen.

I’m using a Nvidia GTX1080Ti and the 430.50 driver.

The monitor layouts look like this (23″,27″,23″), (1080,2160,1080):

On Windows, I used to use LittleBigMouse but haven’t been able to find a suitable alternative for Linux.

Moving Folders Between Libraries in Different Sites Leaves Copies in Both

When I moved a folder from Site 1 Doc Library to Site 2 Doc Library (modern experience in both, btw), I ended up with copies in both locations. Is this expected behavior, that it doesn’t actually MOVE the files? Does this mean that the files in the new location will not retain their Doc IDs and links, as well? Thanks, in advance!

Difference between gnome-shell.css and ubuntu.css, and what are they for?

In ~/.local/share/themes/MyCustomTheme/gnome-shell/gnome-shell.css, I had amended #lockDialogGroup{} to try to show an image in the GDM and made changes to /* Auth Dialogs & Screen Shield */ to change the locking appearance. However, I discovered that these changes did not take effect. Instead, I had to implement the changes to /usr/share/gnome-shell/theme/ubuntu.css to see their effect.

Am I correct to conclude from these observations that:

  1. ubuntu.css is used to control the style of the GNOME Display Manager(Login screen) while gnome-shell.css is used to control the style of the Desktop? If so, why does gnome-shell.css also contain a section on #lockDialogGroup{} and /* Auth Dialogs & Screen Shield */ as they seem redundant?
  2. Would I be able to override /usr/share/gnome-shell/theme/ubuntu.css with my own ~/.local/share/themes/MyCustomTheme/gnome-shell/gnome-shell.css?

Cannot boot into Ubuntu after SSD switch between laptops

I got new laptop in work and I wanted to switch both of my SSDs to it. After I installed SSDs into new laptop I tried to boot. Instead of seeing my GRUB loader, but it takes me right into Windows. When I try to boot manually (selecting SSD with Ubuntu in EFI boot menu) it will just skip the boot and goes to second SSD with Windows again.

I have two SSD. One has Windows on it and one has my Ubuntu. Both were encrypted (Windows with BitLocker and Ubuntu with Luks). I used to dualboot with grub. I tried to use boot-repair, but it didn’t help.

Here is log from it:

I tried also to chroot from live distribution and use grub-update, but still no progress.

Can you please me some idea how to repair my Ubuntu? Boot to Windows looks fine for now.