I'm trying to improve my login system and make it more secure.  $hashed_pass = password_hash($pass, PASSWORD_BCRYPT);   Is this function the best way to safely store password and other information in the database?
It is currently said that MD5 is partially unsafe. Taking this into consideration, I'd like to know which mechanism to use for password protection.  This question,   suggests that hashing multiple times may be a good idea, whereas  suggests using salt.  I'm using PHP. I want a safe and fast password encryption system. Hashing a password a million times may be safer, but also slower. How to achieve a good balance between speed and safety? Also, I'd prefer the result to have a constant number of characters.   The hashing mechanism must be available in PHP It must be safe It can use salt (in this case, are all salts equally good? Is there any way to generate good salts?)   Also, should I store two fields in the database (one using MD5 and another one using SHA, for example)? Would it make it safer or unsafer?  In case I wasn't clear enough, I want to know which hashing function(s) to use and how to pick a good salt in order to have a safe and fast password protection mechanism.  Related questions that don't quite cover my question:
Markdown in chat fails for multi-line messages Simulating the Windows key on an old keyboard Why does the browser renders a newline as space? Variance of sum of $k$ randomly drawn numbers from $1,...,n$. How do I figure the dice and bonuses for attack rolls and damage rolls? I'm building my character, a Half-Elf Ranger, and I'm a little confused about how to work out the attack bonus and the damage bonus.  So, please tell me if I've got this right:   I'm proficient with a longbow. That means my attack roll is 1d20 + prof bonus + Dex modifier. The damage roll however is 1d8 + Dex modifier.   I'm just a little confused about working out the numbers (without even going into spells and when to roll for attack, etc.) Can HTML5 databases and localStorage be shared across subdomains? Why doesn't the definition of a category require an explicit notion of morphisms equality? I am learning basics of the category theory (CT).  I do understand that CT is a modern powerful framework to describe various branches of mathematics in a unified way.  I do admit that category's definition tells a lot about the whole thing and focuses on the most important properties, shadowing unnecessary details. However, the more I go forward, the more it feels like it should explicitly require a notion of morphisms equality (like it does with morphism composition). It feels so because equality or inequality of morphisms arises everywhere, since the very beginning: any commutative diagram eventually reduces to an equality of two different paths and many other things involve equality as well. Even composition is defined grounding upon an (implicit) equality!  I'll try to give an example of my concern. Consider $\mathbb{SET}$. Its objects are sets and morphisms are functions. Now, let's recall that functions are sets as well - to be more precise, a function $f : A \mapsto B$ is a subset of a $A \times B$ obeying certain properties, which I omit. Thus, one could argue that $f$ is both a morphism between objects $A, B \in Obj(\mathbb{SET})$ and an object defined as a set of pairs $\{ (a_1 \in A, b_1 \in B), ..., (a_n \in A, b_n \in B) \}$ and those are equal because both are essentially exactly the same thing.  I hope my concern is clear and I need some kind of "conceptual insight" from knowledgeable people to move forward. Please give me the right perspective. I would like to transfer files between two remote hosts using on local shell, but it seems rsync doesn't support synchronisation if two remotes are specified as follow:  $ rsync -vuar host1:/var/www host2:/var/www The source and destination cannot both be remote.   What other workarounds/commands I could use to achieve similar results? Is there a way to programmatically determine if a font file has a specific Unicode Glyph? I'm working on a project that generates PDFs that can contain fairly complex math and science formulas.  The text is rendered in Times New Roman, which has pretty good Unicode coverage, but not complete. We have a system in place to swap in a more Unicode complete font for code points that don't have a glyph in TNR (like most of the "stranger" math symbols,) but I can't seem to find a way to query the *.ttf file to see if a given glyph is present.  So far, I've just hard-coded a lookup table of which code points are present, but I'd much prefer an automatic solution.  I'm using VB.Net in a web system under ASP.net, but solutions in any programming language/environment would be appreciated.  Edit: The win32 solution looks excellent, but the specific case I'm trying to solve is in an ASP.Net web system.  Is there a way to do this without including the windows API DLLs into my web site? I am using wp_get_attachment_image_src to construct the srcset attribute of an img tag. In that attribute I want to output a comma separated list of image urls along with the image widths.  Using the Media Settings page, I have configured the image sizes to be as follows:   Thumbnail size: 150x150 Medium size: 640x480 Large size: 1024x768 Small size: 278x320   The wp_get_attachment_image_src function returns the correct urls and the correct widths for the image sizes full, medium and small. small is a custom size I added using add_image_size.  If I call wp_get_attachment_image_src( $image_id, 'large' ), the returned array looks like this:  array (     0 =&gt; 'http://localhost/wp-content/uploads/2014/10/image-1024x768.jpg',     1 =&gt; 640,     2 =&gt; 480,     3 =&gt; true, )   Checking the image which can be found at that url turns up the image with the correct dimensions.  Currently i am using the php builtin function  to circumvent this problem, but this function call takes significantly longer than simply accessing the index returned by wp_get_attachment_image_src:  Without getimagesize (mtime before and after execution):   '0.83761000 1415195440' '0.83831600 1415195440'   With getimagesize:   '0.34808000 1415195635'  '0.35323900 1415195635'   What can I do to make wp_get_attachment_image_src return the correct dimensions? Graphics issues after/while installing Ubuntu 16.04/16.10 with NVIDIA graphics I installed or upgraded to Ubuntu 16.04, but I'm having some problems with my graphics card.   The display is blank The display flickers Items on the screen do not display correctly Certain programs complain of graphics issues The computer boots to low-graphics mode Your specific issue may not be here, but try the solutions described in the answers anyway.   This question is very broad, but each one of these issues likely has one solution.    If you are experiencing a login loop, check the last part of my answer.    If you experience one of the listed issues and have your own solution (mine didn't work, or there's a faster way), feel free to post another POLITE answer, describing your problem and how you fixed it.    Those attempting to install Ubuntu, please refer to the section titled: If you are unable to enter a TTY or are trying to install Ubuntu. What I get:  host:~ user$ cat example.txt some texthost:~ stas$   What I want to get:  host:~ user$ cat example.txt some text host:~ stas$   Is there a way I can make cat behave like this?  I'm using bash on Mac OS X. Is there flair for Careers.SO? Are there any image badges like those on  for Careers.SO?         I would like to add a nice image to my website profile. I want to save the list of packages that have installed. I figured it might be the best to list all and diff it with the default set.  Edit: Clarification: I don't want to get the list of installed packages that are installed at the moment. Rather I want to get the list of packages that I added since the default install. How can I restrict various roles with limit in creating nodes of a particular content type System.FinalException: Record is read-only: Trigger.updateCompetitors: line 24 How to execute several commands after each other with one request to the terminal (without using a file)? What is the difference between equation and formula? Sometimes equation and formula are used interchangeably, but I was wondering if there is a difference.  For example, suppose we can calculate a car's fuel efficiency as:  mpg = distance traveled in miles / the fuel used in a gallon   Is that an equation or formula? Consider the following figure from Faraway's Linear Models with R (2005, p. 59).    The first plot seems to indicate that the residuals and the fitted values are uncorrelated, as they should be in a homoscedastic linear model with normally distributed errors. Therefore, the second and third plots, which seem to indicate dependency between the residuals and the fitted values, suggest a different model.  But why does the second plot suggest, as Faraway notes, a heteroscedastic linear model, while the third plot suggest a non-linear model?  The second plot seems to indicate that the absolute value of the residuals is strongly positively correlated with the fitted values, whereas no such trend is evident in the third plot. So if it were the case that, theoretically speaking, in a heteroscedastic linear model with normally distributed errors  $$ \mbox{Cor}\left(\mathbf{e},\hat{\mathbf{y}}\right) = \left[\begin{array}{ccc}1 &amp; \cdots &amp; 1 \\ \vdots &amp; \ddots &amp; \vdots \\ 1 &amp; \cdots &amp; 1\end{array}\right] $$  (where the expression on the left is the variance-covariance matrix between the residuals and the fitted values) this would explain why the second and third plots agree with Faraway's interpretations.  But is this the case? If not, how else can Faraway's interpretations of the second and third plots be justified? Also, why does the third plot necessarily indicate non-linearity? Isn't it possible that it is linear, but that the errors are either not normally distributed, or else that they are normally distributed, but do not center around zero? Which SUSY models are affected by the recent LHCb result? The LHCb has recently  the observation of $B_s \rightarrow \mu^+ \mu^-$ with a branching ratio that agrees with the Standard Model (SM). There are many blog posts about it (See: ).  The result initiated a debate over its implication on Supersymmetry in general, which I don't want to discuss here. But it certainly affects some Supersymmetric models that may have a different prediction than that of the SM.   My questions are,   Which models in particular are affected (or variants of models)? What is the MSSM status? The NMSSM? Does the result affect some of the parameter space of a particular model, or does it rule out an entire model/or variant of a model?