xref: /original-bsd/games/factor/factor.6 (revision abd50c55)
Copyright (c) 1989 The Regents of the University of California.
All rights reserved.

This code is derived from software contributed to Berkeley by
Landon Curt Noll.

Redistribution and use in source and binary forms are permitted
provided that the above copyright notice and this paragraph are
duplicated in all such forms and that any documentation,
advertising materials, and other materials related to such
distribution and use acknowledge that the software was developed
by the University of California, Berkeley. The name of the
University may not be used to endorse or promote products derived
from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.

@(#)factor.6 5.2 (Berkeley) 02/01/90


By: Landon Curt Noll chongo@toad.com, ...!{sun,tolsoft}!hoptoad!chongo

chongo <for a good prime call: 391581 * 2^216193 - 1> /\oo/\

FACTOR 6 ""
C 7
NAME
factor, primes - factor a number, generate primes
SYNOPSIS
factor [ number ] ...

primes [ start [ stop ]]

DESCRIPTION
The factor utility will factor integers between -2147483648 and 2147483647 inclusive. When a number is factored, it is printed, followed by a ``:'', and the list of factors on a single line. Factors are listed in ascending order, and are preceded by a space. If a factor divides a value more than once, it will be printed more than once.

When factor is invoked with one or more arguments, each argument will be factored.

When factor is invoked with no arguments, factor reads numbers, one per line, from standard input, until end of file or error. Leading white-space and empty lines are ignored. Numbers may be preceded by a single - or +. Numbers are terminated by a non-digit character (such as a newline). After a number is read, it is factored. Input lines must not be longer than 255 characters.

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.

DIAGNOSTICS
Out of range or invalid input results in `ouch' being written to standard error.
BUGS
Factor cannot handle the ``10 most wanted'' factor list, primes won't get you a world record.