shm_remove_var
    (PHP 3>= 3.0.6, PHP 4 )
shm_remove_var -- Removes a variable from shared memory
    
Description
int 
shm_remove_var ( int id, int variable_key)
     Removes a variable with a given variable_key
     and frees the occupied memory.
    
Note: 
      This function does not work on Windows systems.