DESCRIPTION
 The 
primes utility prints primes in ascending order, one per line, starting at or above 
start and continuing until, but not including 
stop. The 
start value must be at least 0 and not greater than 
stop. The 
stop value must not be greater than 4294967295. The default value of 
stop is 4294967295.
When the primes utility is invoked with no arguments, start is read from standard input. stop is taken to be 4294967295. The start value may be preceded by a single ‘+'. The start value is terminated by a non-digit character (such as a newline). The input line must not be longer than 255 characters. When given the -d argument, primes prints the difference between the current and the previous prime.