Description
int 
strncmp ( string str1, string str2, int len )
     This function is similar to strcmp(), with the
     difference that you can specify the (upper limit of the) number
     of characters (len) from each string to be
     used in the comparison.
    
     Returns < 0 if str1 is less than
     str2; > 0 if str1
     is greater than str2, and 0 if they are
     equal.
    
     Note that this comparison is case sensitive.
    
     See also preg_match(),
     strncasecmp(),
     strcasecmp(), substr(),
     stristr(), strcmp(), and
     strstr().