Return to jot.1 CVS log

Up to [local] / src / usr.bin / jot

random numbers are obtained via arc4random(3), not random(3);
from FreeBSD PR 54879, forwarded by otto@;

ok otto@

.\"	$OpenBSD: jot.1,v 1.12 2003/12/18 11:51:13 jmc Exp $
.\"	$NetBSD: jot.1,v 1.2 1994/11/14 20:27:36 jtc Exp $
.\"
.\" Copyright (c) 1993
.\"	The Regents of the University of California.  All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 3. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\"	@(#)jot.1	8.1 (Berkeley) 6/6/93
.\"
.Dd June 6, 1993
.Dt JOT 1
.Os
.Sh NAME
.Nm jot
.Nd print sequential or random data
.Sh SYNOPSIS
.Nm jot
.Bk -words
.Op Fl cnr
.Op Fl b Ar word
.Op Fl p Ar precision
.Op Fl s Ar string
.Op Fl w Ar word
.Oo Ar reps Oo Ar begin Oo Ar end
.Oo Ar s Oc Oc Oc Oc
.Ek
.Sh DESCRIPTION
.Nm
is used to print out increasing, decreasing, random,
or redundant data, usually numbers, one per line.
.Pp
The options are as follows:
.Bl -tag -width "-p precision"
.It Fl b Ar word
Just print
.Ar word
repetitively.
.It Fl c
This is an abbreviation for
.Fl w Ic %c .
.It Fl n
Do not print the final newline normally appended to the output.
.It Fl p Ar precision
Print only as many digits or characters of the data
as indicated by the integer
.Ar precision .
In the absence of
.Fl p ,
the precision is the greater of the numbers
.Ar begin
and
.Ar end .
The
.Fl p
option is overridden by whatever appears in a
.Xr printf 3
conversion following
.Fl w .
.It Fl r
Generate random data.
By default,
.Nm
generates sequential data.
.It Fl s Ar string
Print data separated by
.Ar string .
Normally, newlines separate data.
.It Fl w Ar word
Print
.Ar word
with the generated data appended to it.
Octal, hexadecimal, exponential, ASCII, zero-padded,
and right-adjusted representations
are possible by using the appropriate
.Xr printf 3
conversion specification inside
.Ar word ,
in which case the data is inserted rather than appended.
.El
.Pp
The last four arguments indicate, respectively,
the maximum number of data, the lower bound, the upper bound,
and the step size or, for random data, the seed.
While at least one of them must appear,
any of the other three may be omitted, and
will be considered as such if given as
.Ql - .
Any three of these arguments determines the fourth.
If four are specified and the given and computed values of
.Ar reps
conflict, the lower value is used.
If fewer than three are specified, defaults are assigned
left to right, except for
.Ar s ,
which assumes its default unless both
.Ar begin
and
.Ar end
are given.
.Pp
Defaults for the four arguments are, respectively,
100, 1, 100, and 1, except that when random data are requested,
.Ar s
defaults to a seed depending upon the time of day.
.Ar reps
is expected to be an unsigned integer,
and if given as zero is taken to be infinite.
.Ar begin
and
.Ar end
may be given as real numbers or as characters
representing the corresponding value in ASCII.
The last argument must be a real number.
.Pp
Random numbers are obtained through
.Xr arc4random 3 .
The name
.Nm
derives in part from
.Xr iota ,
a function in APL.
.Sh EXAMPLES
Print 21 evenly spaced numbers increasing from \-1 to 1:
.Pp
.Dl $ jot 21 \-1 1.00
.Pp
Generate the ASCII character set:
.Pp
.Dl $ jot \-c 128 0
.Pp
Generate the strings xaa through xaz:
.Pp
.Dl $ jot \-w xa%c 26 a
.Pp
Generate 20 random 8-letter strings:
.Pp
.Dl "$ jot \-r \-c 160 a z | rs \-g 0 8"
.Pp
Infinitely many
.Xr yes 1 's
may be obtained through:
.Pp
.Dl $ jot \-b yes 0
.Pp
Thirty
.Xr ed 1
substitution commands applying to lines 2, 7, 12, etc. is the result of:
.Pp
.Dl $ jot \-w %ds/old/new/ 30 2 \- 5
.Pp
The stuttering sequence 9, 9, 8, 8, 7, etc. can be
produced by suitable choice of precision and step size:
.Pp
.Dl $ jot 20 9 0 \-.475
.Pp
Create a file containing exactly 1024 bytes:
.Pp
.Dl $ jot \-b x 512 > block
.Pp
To set tabs four spaces apart starting
from column 10 and ending in column 132, use:
.Pp
.Dl $ expand \-`jot \-s, \- 10 132 4`
.Pp
To print all lines 80 characters or longer:
.Pp
.Dl $ grep `jot \-s \&"\&" \-b . 80`
.Sh SEE ALSO
.Xr ed 1 ,
.Xr expand 1 ,
.Xr rs 1 ,
.Xr yes 1 ,
.Xr arc4random 3 ,
.Xr printf 3