PHP Srand () function

PHP’s srand() function is used to populate the random number generator rand(). The srand() function sets the starting point for generating a series of pseudo-random numbers. If srand() is not called, rand() seed is set as if srand (1) was called when the program starts. The srand() function starts the random number generator using seed (arg) or a random value if no seed (arg) is specified.Syntax:

srand ($seed)

Parameters:This function takes one seed parameter. This parameter is optional and is of type integer. It defines the initial value.Return value:This function does not return any value.Examples:

Input: srand (time()); Output: 1793542495 Input: srand (5) Output: 3

The following programs illustrate the srand() function in PHP:

When the timestamp is used as the $seed value along with srand() function:   srand (time()); echo (rand());  
?> Output:

1793542495

When a custom seed is passed as an argument to the srand() function:  
srand (5); echo (rand (1, 10));  
?> Output:

3

Important points to note:

• The srand() function can be used to generate random numbers.
• The srand() function does not generate the same sequence of random numbers as the rand() function.
• It has no return value.

Recommendations :
http://php.net/manual/en/function.srand. php