In PHP you should be careful working with floating point number comparisons because sometimes the result that you get can be unexpected and unpredictable even if it looks pretty obvious. Here is an example. Can you guess what will be the result?

<?php
$a = 0.7;
$b = 0.1;
$c = $a + $b;
if ($c == 0.8) {
   echo '$c == 0.8';
} else {
   echo '$c!=0.8';
}

This post will continue one of my previous posts Reading file list from a mapped Windows network drive.

Recently, I have had a challenge with reading files from a directory using a wildcard pattern (i.e. " *.jpg "). Obviously, regular is_file() or file_exists() functions do not work in this case. So, I started looking for a solution that could help me with my problem.

Luckily, there is a function glob() that searches for the pathnames matching given pattern.

<?php
foreach(glob('*.jpg') as $image) {
  if( !is_dir($image) ) {
    $images[] = $image;
  }
}
?>

More or less, every clever IT professional understands that big corporations such as Microsoft and Google are able to read correspondences of Gmail and Skype users.

Recently, I found a post where guys from The H Security explain how they found out that Microsoft actually monitors what you write in Skype.

Actually, it is not a big secret. Everyone who uses Skype, must agree with the item that Microsoft could read everything you write (see privacy statement in Skype). Especially I liked that "Skype may capture and manually review instant messages or SMS in connection". However, it's interesting why they pay their attention to HTTPS links and ignore HTTP.

So, if you use Skype for Internet communication, you should know that it is not 100% private.

If you ever need to concatenate fields that are empty or equal null, you may run into troubles because MySQL doesn't concatenate NULL-fields as you might expect - if there is one of the concatenating fields equals NULL, the whole concatenating value will be NULL.

See the following dummy table:

firstname | middlename | lastname | email
John        J.           Smith      [email protected]
Amanda      NULL         Smith      [email protected]

As you can see Amanda Smith doesn't have middle name. So, if you now run a query that will try to concatenate first name, middle name and last name, you'll get NULL value instead of expected concatenated value.

In this release JQuery core developers threw out the support for Internet Explorer 6, 7 and 8 (Yay!). Thanks to this, the size of the library has decreased by 12% and now it's smaller and faster. It can be even smaller if you make your own build, disabling some of  built-in default modules (there is 12 of them).

Those who need old IE support should remain on the branch 1.x, which will continue supporting old IE versions.

Web developers often need to get visitor's IP address to use it in web applications. This can be used in internal traffic analytics tools, or as a part of security measures.

Most common and standard method of getting visitor's IP address is getting the value "REMOTE_ADDR" from the global PHP array $_SERVER:

<?php
$visitor_ip = $_SERVER['REMOTE_ADDR'];

However, standard PHP $_SERVER['REMOTE_ADDR'] value not necessarily contains the originating visitor's IP address because, for example, visitor can use a proxy server to access your web site. Using PHP we could try to detect user's IP address even if he uses proxy, but keep in mind that there is no guarantee that IP address that you get is 100% accurate (e.g. proxy can be anonymous).

There is a lot of different blogs exist in the Internet. However, every day people set up tons of new blogs, and at the same time huge number of blogs die every day. So, why would people create and run their own blogs?

Last week I ran into a situation when I had to read directory file list from a mapped Windows network drive. At your very first look it may seem pretty simple. It is! However, there is a little trick - Windows may require your network/domain credentials, and then standard PHP functions such as opendir() won't be able to access the directory. Fortunately, the solution is pretty simple: