Quickest way to check whether or not file exists
What's the best way to check if a file exists in C?
Endnotes do not be superscript and add a space Tabs in output file written by xelatex and pdflatex are different When installing an application, the application lists permissions that it needs to perform its  functions.    I am creating this list of the the system defined permissions and a description of what they mean. It is a community wiki so if new permissions are added in the future they can be added to this list. I suspected that installing xfce4 cause some issues in Ubuntu so I removed them using apt-get remove xfce4 xfce4-goodeis.  But when I ran 'dpkg -l' I still can see some libraries and packages for xfce4:  $ dpkg -l | grep -i xfce rc  libexo-1-0:amd64                              0.10.2-2                                 amd64        Library with extensions for Xfce rc  libgarcon-1-0                                 0.2.1-1                                  amd64        freedesktop.org compliant menu implementation for Xfce rc  libxfce4ui-1-0                                4.11.0-0ubuntu1~ppa0.13.10.1             amd64        widget library for Xfce - Gtk+2 variant rc  libxfce4ui-common                             4.11.0-0ubuntu1~ppa0.13.10.1             all          common files for libxfce4ui rc  libxfce4util6                                 4.10.1-1                                 amd64        Utility functions library for Xfce4 rc  libxfcegui4-4                                 4.10.0-2                                 amd64        Basic GUI C functions for Xfce4 rc  libxfconf-0-2                                 4.10.0-2                                 amd64        Client library for Xfce4 configure interface rc  mousepad                                      0.3.0-2                                  amd64        simple Xfce oriented text editor rc  thunar                                        1.6.3-1ubuntu1                           amd64        File Manager for Xfce rc  xfce4-appfinder                               4.10.1-1                                 amd64        Application finder for the Xfce4 Desktop Environment rc  xfce4-clipman                                 2:1.2.3-2ubuntu1                         amd64        clipboard history utility rc  xfce4-mixer                                   1:4.10.0-1ubuntu2                        amd64        Xfce mixer application rc  xfce4-notes                                   1.7.7-3ubuntu2                           amd64        Notes application for the Xfce4 desktop rc  xfce4-panel                                   4.10.1-1ubuntu1                          amd64        panel for Xfce4 desktop environment rc  xfce4-power-manager                           1.2.0-2ubuntu1                           amd64        power manager for Xfce desktop rc  xfce4-session                                 4.10.1-1ubuntu1                          amd64        Xfce4 Session Manager rc  xfce4-settings                                4.11.1-0ubuntu1~ppa0.13.10.1             amd64        graphical application for managing Xfce settings rc  xfce4-terminal                                0.6.2-3ubuntu1.1                         amd64        Xfce terminal emulator rc  xfce4-volumed                                 0.2.0-0ubuntu1                           amd64        volume keys daemon rc  xfdesktop4                                    4.11.2-0ubuntu1~ppa0.13.10.1             amd64        xfce desktop background, icons and root menu manager rc  xfwm4                                         4.11.1-0ubuntu1~ppa0.13.10.1             amd64        window manager of the Xfce project   I copy-pasted all these packages\libraries to form an apt-get remove command to remove all of these dependencies, and the command ran normally, but running dpkg -l | grep -i xfce showed these dependencies again !  Why are these dependencies still installed ? Should we use plural or singular for a fraction of a mile? I have seen people say both 0.25 mile and 0.25 miles. Should we use plural or singular for a fraction of a mile? Do you think that "was going to be" or "would be" could be used as past tense of will?     I thought this book was going to be your choice.        I thought this book would be your choice.   Do these two sentences basically mean the same thing or are they slightly different? Deleting an element from an array in PHP How do I print a double value with full precision using cout? Can we query the info from "Data Management -> Storage Usage" through SOAP API? Selecting ARIMA orders based on ACF-PACF vs. auto.arima What is the best way to remove duplicate rows from a fairly large SQL Server table (i.e. 300,000+ rows)?  The rows, of course, will not be perfect duplicates because of the existence of the RowID identity field.  MyTable  RowID int not null identity(1,1) primary key, Col1 varchar(20) not null, Col2 varchar(2048) not null, Col3 tinyint not null Doesn't the end of Looper create a time paradox? I guess this is more a question about the nature of time travel more than anything else.  At the end of the movie,      Joe shoots himself in a field and changes the course of history.   Does this create a paradox as it changes the history that led up to that point?      If his future self had never existed he'd never have gone on the mission he did and thus he never would have ended up in the field.   Once he did what he did, he could no longer have done it, and so theoretically, time and space should have just folded in on itself and popped out of existence.  Is there something I'm missing that would explain how the movie could have ended where it did without the events at the beginning to lead it there? I had read a story / article about artificial intelligence, I think it was last year (2012) but I'm not sure when it was published. It was on an online blog for an institute I believe. I am telling the story in quotes, just to demarcate where the story begins and ends.  In the story, a scientist is trying to build a perfect AI system which can respond to human interaction perfectly. Apparently the only way this is possible is to make the computer believe that it is human. He creates what he believes is the solution, and asks a friend to volunteer for a test, and the friend agrees. For the test the friend is supposed to step into a tank full of a liquid. As soon as he enters the tank, he is told, he will lose all his sensations - no vision, no hearing etc. After entering the tank, he talks to the computer and responds, and isn't able to recognise that he is in fact talking to a computer. After some time (days? Don't remember) has passed, he begins to worry - why is he still trapped in the tank? At this point the scientist tells him that he is in fact the computer he has made, the memory that he has of the human life till the time he enters the tank has been implanted in the machine, so he thinks he is human. He is not in a tank, he is a computer, and that is why he can't see or feel anything. The story ends here.  It is told from the perspective of the computer itself, but since it is an article in a science blog / forum for a technical college, it feels like you're reading an actual experiment when you start reading. It was a rather nice surprise ending to the story in my opinion. I just can not seem to be able to locate the article / story anywhere. Can somebody who might have read this help me? Even just pointing me in the direction of the site it is hosted on would be great. Is the set of all unitary matrices in $M_2(\mathbb{C})$ is compact? I can show that as determinant map is continuous so unitary matrices are closed but how to show they are bounded?   Please help. I took a look at  but my question is not the same.  I have unique keys encrypting each plaintext (in CBC mode, AES-256) and I do not use a key to encrypt more than one plaintext. Is it insecure to use null IVs in this case? If it is insecure, why? Do not delete good duplicates! Using indefinite articles before adjectives: "Let's have a good breakfast" Let's have breakfast    Let's have a good breakfast      I've learned that indefinite articles aren't used before uncountable nouns, so why is a used before the adjective "good" here?    Is there an exception to the rules or is it wrong? Seriously, it was fun and all, but I can't and I don't want to stay married to the same woman for the rest of my life - one real life marriage is enough..  Is there a lawyer or process of some kind in the world of Skyrim, and if not, who could help me divorce her?  If all else should fail, (sigh), do I have to take her to the backyard, thwack her head with the shovel and dig a shallow grave? How are ssl certificates verified? What is the series of steps needed to securely verify a ssl certificate?  My (very limited) understanding is that when you visit an https site, the server sends a certificate to the client (the browser) and the browser gets the certificate's issuer information from that certificate, then uses that to contact the issuerer, and somehow compares certificates for validity.     How exactly is this done?  What about the process makes it immune to man-in-the-middle attacks? What prevents some random person from setting up their own verification service to use in man-in-the-middle attacks, so everything "looks" secure? SEO regarding using separate  tags for the logo and website name Is is true &lt;h1&gt; tag should not have more than 1 on every page for SEO?   Every pages on the header, it includes and &lt;h1&gt; tag. Website Name which show an image from logo class, like this:  &lt;div id="header"&gt;   &lt;h1 class="logo"&gt;      &lt;a href="#"&gt;Website Name&lt;/a&gt;   &lt;/h1&gt; &lt;/div&gt;   and I also include &lt;h1&gt; on the contact page, help, etc and article page for example:  &lt;h1&gt;Contact Us&lt;/h1&gt; &lt;h1&gt;Name of the Article Title here&lt;/h1&gt;   On the homepage, it just has one &lt;h1&gt; for the logo Site Name... other pages have 2 &lt;h1&gt; tags