After restarting my ubuntu is stuck on a black screen with some boot messages after restarting. I tried to use the recovery mode and use the dpgk and fsck commands, the dpgk didn't change anything and fsck wouldn't work because the system is in read/write mode.   What are my options here? I have some important files on the installation so I can't just reinstall.  Might be worth mentioning that I have a dual boot, grub menu is working fine, and that I restarted initially because I couldn't open terminals any more. Version is Ubuntu 18.04.  The last boot message is "Started the Apache HTTP server.dispatcher service .... ystem changes.pp link was shut down".  Thanks for reading, any help is greatly appreciated!
I am trying to boot Ubuntu on my computer.  When I boot Ubuntu, it boots to a black screen.  How can I fix this? Table of Contents:
C's strtok() and read only string literals char *strtok(char *s1, const char *s2)      repeated calls to this function break string s1 into "tokens"--that is   the string is broken into substrings,   each terminating with a '\0', where   the '\0' replaces any characters   contained in string s2. The first call   uses the string to be tokenized as s1;   subsequent calls use NULL as the first   argument. A pointer to the beginning   of the current token is returned; NULL   is returned if there are no more   tokens.   Hi,   I have been trying to use strtok just now and found out that if I pass in a char* into s1, I get a segmentation fault. If I pass in a char[], strtok works fine.   Why is this?  I googled around and the reason seems to be something about how char* is read only and char[] is writeable. A more thorough explanation would be much appreciated. How can I rename many files at once? Turn off text message (SMS) sync to Exchange email account I recently started using a Samsung Galaxy S4 and one of the features in a synchronization between text messages and email accounts.  When a text message comes in it throws a copy into my Exchange email accounts that are one the phone. I want to turn this feature off but cannot find a setting for it anywhere.  Any ideas? Can you attach a UIGestureRecognizer to multiple views? Gradient steepest direction and normal to surface? From this , I now understand the gradient to be the directional derivative that returns the steepest slope at a point. However, reading my textbooks, they all say that the gradient is normal to the tangent plane. In the above SE question, the gradient sounds like it should be parallel to a direction in the $xy$ plane, not actually up on the surface.   My question is therefore do I have a misunderstanding of the tangent plane, gradient or directional derivative?   In addition, I question how the gradient always passes through the origin or the $xy$ plane? If for instance in the graphic, the gradient had been another direction (say horizontal), then it wouldn't pass through the origin! In addition, the gradient of other points in the graphic would satisfy this example. Many thanks! QT MySql connectivity using Windows XP, Qt Creator 4.5.2(windows 32 bit) How can I enable multiple users login at a time in remote system? Recently we bought dedicated server with Windows Server 2012 Standard.It's allowing 2 people at a time.So I want to allow more people at a time.  How can I do this? cp -r is meant to copy files recursively, and cp -R for copying directories recursively. But I've checked, and both appear to copy both files and directories, the same thing. So, what's the difference actually? How can I use a command to delete all files in Downloads whose dates added are greater than 1 year? I am using a Mac. How can I use a command to delete all files in ~/Downloads whose dates added are greater than 1 year? How do you pass a function as a parameter in C? I want to create a function that performs a function passed by parameter on a set of data. How do you pass a function as a parameter in C? Is there a way to show the console in a Windows application?  I want to do something like this:  static class Program {     [STAThread]     static void Main(string[] args) {         bool consoleMode = Boolean.Parse(args[0]);          if (consoleMode) {             Console.WriteLine("consolemode started");             // ...         } else {             Application.EnableVisualStyles();             Application.SetCompatibleTextRenderingDefault(false);             Application.Run(new Form1());         }     } } How do I get a file extension in PHP? We are conducting a test on a rare disease. A positive result means that, according to the test, the subject is infected. The following characteristics are known about the test and the disease: If a person is infected, the person has a $95\%$ chance of testing positive. When a healthy person is tested, the test has a $99\%$ chance of giving a negative result. A mere $0.1\%$ of the population is infected with the disease. If a person is tested positive for the disease. What is the probability that the person actually has the disease? I don't understand how to write the conditional probabilities if someone can explain to me than I should know how to solve it, but I'm not sure how to convert the text into the mathematics language. I'm an avid book collector, and I was wondering what house has the most bookshelves in Skyrim. I currently only own the Whiterun house, which has 2 bookshelves of 2 shelves each.  Is there a house I could buy that has more bookshelves?  Edit  Since not all bookshelves hold the same number of books, I'm looking for the house that has the most spaces on bookshelves for books, not necessarily the most bookshelves I was peacefully playing GTA Online (yeah, was killing someone coming out of ls customs) then a hacker came and killed me using explosive ammos, I called him a hacker and he teleported to me and gave me 790k. I know that people get banned for receiving this kind of money, what should I do to avoid the ban? calculate slope for a road network I am working on a road network for routing operations using postgis and QGIS.    I am new to both of these tools and need to calculate the slope for each edge (by retrieving the Z value for the start and end node for the edge from a raster). Any ideas of the best approach to this?   I know postgis can dump points and get the value from a raster, but can I get the slope attribute to the edge without breaking the network topology (with edges that have corresponding start/end nodes) using this method?   thanks What is proper way to update D8 DEV? I think that  is pretty good prima-facia evidence that  is just facilitating the deposition of crap. How to define orbital angular momentum in other than three dimensions? How to install TeX on Android phones? I used  app in my Android phone. But this app does not support XeLaTeX and requires an internet connection to be used.  Is there any distribution of TeX for Android? How I can install TeX on my Android phone?