$s1 = "PHP is a general-purpose programming language originally designed for web development";
$s2 = "PHP programming language";
$s3 = "PHP c";
echo strncasecmp($s1, $s2, 3) . "<br />"; // equal
echo strncasecmp($s1, $s2, 5) . "<br />"; // s1 < s2
echo strncasecmp($s1, $s3, 5); // s1 > s3
/*
run:
0
-7
6
*/