Added README and changed binary to dotted binary

README.md

@@ -0,0 +1,24 @@
+# Netcalc #
+This is a simple CLI network calculator made in PHP. Usage is pretty straight
+forward. For example, let say you want to know how many usable addresses you
+will get with a 26 bit netmask, simply run the script as below:
+
+    php netcalc.php 26
+
+The above command will give you the following outut:
+
+    Netmask
+    -------
+    In slash notation: 26
+    In dotted decimal: 255.255.255.192
+    In dotted binary: 11111111.11111111.11111111.11000000
+
+    Network size
+    ------------
+    Total number of addresses: 64
+    Number of usable addresses for hosts: 62
+
+## Copyright ##
+Netcalc is written by Jack-Benny Persson and released under GNU GPL version 2.
+
+

netcalc.php

@@ -59,6 +59,11 @@ function print_netmask($number)
     // Put it together in a binary string
     $binary = "$ones$zeros";
 
+    // Make it dotted binary format
+    $dotted_binary = substr_replace($binary, ".", 8, 0);
+    $dotted_binary = substr_replace($dotted_binary, ".", 17, 0);
+    $dotted_binary = substr_replace($dotted_binary, ".", 26, 0);
+
     // Make it dotted decimal format
     $firstOctet = base_convert(substr($binary, 0, 8), 2, 10);
     $secondOctet = base_convert(substr($binary, 8, 8), 2, 10);
@@ -69,9 +74,8 @@ function print_netmask($number)
     print "Netmask\n" ;
     print "-------\n";
     print "In slash notation: $mask\n";
-    print "In binary: ";
+    print "In dotted decimal: $firstOctet.$secondOctet.$thirdOctet.$forthOctet\n";
-    print $binary . "\n";
+    print "In dotted binary: $dotted_binary";
-    print "In dotted decimal: $firstOctet.$secondOctet.$thirdOctet.$forthOctet";
     print "\n\n";
 }