mcrypt_generic_init
  (PHP 4 >= 4.0.2, PHP 5)
mcrypt_generic_init — This function initializes all buffers needed for encryption
  
 
  Description
  
   int mcrypt_generic_init
    ( resource $td
   , string $key
   , string $iv
   )
  
  
 
  Parameters
  
   
    - 
     td
     
- 
      
       The encryption descriptor.
       
- 
     key
     
- 
      
       The maximum length of the key should be the one obtained by calling
       mcrypt_enc_get_key_size() and every value smaller
       than this is legal.
       
- 
     iv
     
- 
      
       The IV should normally have the size of the algorithms block size, but
       you must obtain the size by calling
       mcrypt_enc_get_iv_size(). IV is ignored in ECB. IV
       MUST exist in CFB, CBC, STREAM, nOFB and OFB modes. It needs to be
       random and unique (but not secret). The same IV must be used for
       encryption/decryption. If you do not want to use it you should set it
       to zeros, but this is not recommended.
       
 
 
  Return Values
  
   The function returns a negative value on error, -3 when the key length
   was incorrect, -4 when there was a memory allocation problem and any
   other return value is an unknown error. If an error occurs a warning will
   be displayed accordingly. FALSE is returned if incorrect parameters
   were passed.