php man page for strnatcmp

STRNATCMP(3)								 1							      STRNATCMP(3)

strnatcmp - String comparisons using a ";natural order" algorithm

SYNOPSIS
       int strnatcmp (string  $str1, string  $str2)

DESCRIPTION
	This  function	implements  a comparison algorithm that orders alphanumeric strings in the way a human being would, this is described as a
       "natural ordering". Note that this comparison is case sensitive.

PARAMETERS
	      o $str1
		- The first string.

	      o $str2
		- The second string.

RETURN VALUES
	Similar to other string comparison functions, this one returns < 0 if $str1 is less than $str2; > 0 if $str1 is greater than $str2, and  0
       if they are equal.

EXAMPLES
	An  example  of  the  difference between this algorithm and the regular computer string sorting algorithms (used in strcmp(3)) can be seen
       below:

       <?php
       $arr1 = $arr2 = array("img12.png", "img10.png", "img2.png", "img1.png");
       echo "Standard string comparison
";
       usort($arr1, "strcmp");
       print_r($arr1);
       echo "
Natural order string comparison
";
       usort($arr2, "strnatcmp");
       print_r($arr2);
       ?>

       The above example will output:

       Standard string comparison
       Array
       (
	   [0] => img1.png
	   [1] => img10.png
	   [2] => img12.png
	   [3] => img2.png
       )

       Natural order string comparison
       Array
       (
	   [0] => img1.png
	   [1] => img2.png
	   [2] => img10.png
	   [3] => img12.png
       )

SEE ALSO
       preg_match(3), strcasecmp(3), substr(3), stristr(3), strcmp(3), strncmp(3), strncasecmp(3), strnatcasecmp(3), strstr(3),  natsort(3),  nat-
       casesort(3).

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