When amount of memory to be allocated is known beforehand i.e. at the the time of compilation, it is known as Static Memory Allocation. Once the memory is allocated statically, it cannot be deallocated during program run. So it leads to wastage of storage space.

Example:

int A[100];

When amount of memory to be allocated is not known beforehand, rather it is determined at the time of program run, it is called Dynamic Memory Allocation. It leads to efficient utilization of storage space.

Example:

cout << " Enter number of elements: ";

cin >> N;

int *A = new int[N]; // dynamic memory allocation

A Peoplesoft database is expression which point out a database containing Peoplesoft objects. For Oracle and only for Oracle, Peoplesoft consists in 3 schemas namely:

- PS (PSDBOWNER table owner),

- PEOPLE (for connection checking) and

- SYSADM (by default), the last one contains all the objects/data.

One of the database objects is connected with single Oracle schema, and all processes that connect to the database use the standard PSFT login procedure. PSFT login is used because to refer to the collection of tables in the administrative schema within an Oracle database. Every process that makes a 2-tier connection to the database identifies itself with a PSFT user or operator ID. Hence the interaction goes.

Every architecture rely on a database that is easy to maintain and gets easily configured Amazon uses the database by the name SimpleDB. This is the database that is used for cloud architecture to track the statuses of the components. The component of the system are asynchronous and discrete, it requires capturing the state of the system so that in any failure the user can easily revert back to its normal configuration. SimpleDB is schema-less database and there is no need to define the structure before the creation of any data. Every controller in the database defines their own structure and link the data to a job.

Security is one of the major aspects which come with any application and service used by the user. Companies or organizations remain much more concerned with the security provided with the cloud. There are many levels of security which has to be provided within cloud environment such as:

• Identity management: it authorizes the application service or hardware component to be used by authorized users.

• Access control: permissions has to be provided to the users so that they can control the access of other users who are entering the in the cloud environment.

• Authorization and authentication: provision should be made to allow the authorized and authenticated people only to access and change the applications and data.

Opendir():- It opens the directory. This function returns a directory stream on success and FALSE and an error on failure.

Syntax:

Opendir(directory, context)

Context is a set of options that can modify the behavior of a stream

Example: opens sample directory.

$dir = opendir("directory");

Readdir(): It returns an entry from a directory handle opened by opendir().

Syntax:

Readdir(dir_stream)

Example:

$file = readdir($dir);

closedir(): It closes a directory handle opened by opendir().

Syntax:

closedir(dir_stream)

Example:

$file = close($dir);

The mail() function of PHP is quite robust for sending bulk emails. A SMTP server can also be directly used from the script. PHPmailer class can be used for sending emails.

Following are the steps to create a simple AD rotator script without using database in PHP:

- All the ad’s can be collected in one place and be displayed randomly.rand() function can be used for this purpose.

- In order to NOT use any database, a flat file can be used to store the ad’s.

- In order to store the Ad’s information (HTML code), a flat file say “ad.txt” can be created.

- The random number can be stored in a variable 

$result_random=rand(1, 100);

- Conditions can be checked to display the ad’s.

if($result_random<=70)

{

      echo "Display ad1";

}

Permissions in PHP are very similar to UNIX. Each file has three types of permissions – Read, write and execute. Permissions can be changed using the change mode or CHMOD command. CHMOD is followed by 3 digit number specifying the permission type. CHMOD 777 is for Read, Write and execute.

Unnecessary permissions can be stripped off using UNMASK command.

Unmask (777);