Question: after exporting to p.12 in MacOSX, can i run the following 3 step in Linux? Or i must get it done in the same machine where i export to P.12 before i upload to Linux server to use with my php script?

```
openssl pkcs12 -clcerts -nokeys -out apns-dev-cert.pem -in apns-dev-cert.p12
openssl pkcs12 -nocerts -out apns-dev-key.pem -in apns-dev-key.p12
openssl rsa -in apns-dev-key.pem -out apns-dev-key-noenc.pem

```

Answer: 
```
double dArray[][];

```

is Array-of-arrays while

```
double dArray[,];

```

is a two dimentional array.

it's easy enough to look them up.

[MSDN Reference link](http://msdn.microsoft.com/en-us/library/aa288453%28v=vs.71%29.aspx)
The first is an array of `double` arrays, meaning each separate element in `dArray` can contain a different number of doubles depending on the length of the array.

```
double[][] dArray = new double[3][];
dArray[0] = new double[3];
dArray[1] = new double[2];
dArray[2] = new double[4];

           Index
        0       1       2
      -----   -----   -----
L  1  |   |   |   |   |   |
e     -----   -----   -----
n  2  |   |   |   |   |   |
g     -----   -----   -----
t  3  |   |           |   |
h     -----           -----
   4                  |   |
                      -----

```

The second is called a multidimensional array, and can be thought of as a matrix, like rows and columns.

```
double[,] dArray = new dArray[3, 3];

         Column
        0   1   2
      -------------
   0  |   |   |   |
R     -------------
o  1  |   |   |   |
w     -------------
   2  |   |   |   |
      -------------

```