JOT(1) BSD General Commands Manual JOT(1)
jot -- print sequential or random data
jot [-cnr] [-b word] [-w word] [-s string] [-p precision] [reps [begin [end [s]]]]
The jot utility is used to print out increasing, decreasing, random, or redundant data, usu-
ally numbers, one per line.
The following options are available:
-r Generate random data instead of the default sequential data.
Just print word repetitively.
Print word with the generated data appended to it. Octal, hexadecimal, exponential,
ASCII, zero padded, and right-adjusted representations are possible by using the
appropriate printf(3) conversion specification inside word, in which case the data
are inserted rather than appended.
-c This is an abbreviation for -w %c.
Print data separated by string. Normally, newlines separate data.
-n Do not print the final newline normally appended to the output.
Print only as many digits or characters of the data as indicated by the integer
precision. In the absence of -p, the precision is the greater of the precisions of
begin and end. The -p option is overridden by whatever appears in a printf(3) con-
version following -w.
The last four arguments indicate, respectively, the 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 -. Any three of these arguments determines the fourth. If four are specified and the
given and computed values of reps conflict, the lower value is used. If fewer than three
are specified, defaults are assigned left to right, except for s, which assumes its default
unless both begin and end are given.
Defaults for the four arguments are, respectively, 100, 1, 100, and 1, except that when ran-
dom data are requested, the seed, s, is picked randomly. The reps argument is expected to
be an unsigned integer, and if given as zero is taken to be infinite. The begin and end
arguments may be given as real numbers or as characters representing the corresponding value
in ASCII. The last argument must be a real number.
Random numbers are obtained through random(3). The name jot derives in part from iota, a
function in APL.
jot 21 -1 1.00
prints 21 evenly spaced numbers increasing from -1 to 1. The ASCII character set is gener-
jot -c 128 0
and the strings xaa through xaz with
jot -w xa%c 26 a
while 20 random 8-letter strings are produced with
jot -r -c 160 a z | rs -g 0 8
Infinitely many yes's may be obtained through
jot -b yes 0
and thirty ed(1) substitution commands applying to lines 2, 7, 12, etc. is the result of
jot -w %ds/old/new/ 30 2 - 5
The stuttering sequence 9, 9, 8, 8, 7, etc. can be produced by suitable choice of step size,
jot - 9 0 -.5
and a file containing exactly 1024 bytes is created with
jot -b x 512 > block
Finally, to set tabs four spaces apart starting from column 10 and ending in column 132, use
expand -`jot -s, - 10 132 4`
and to print all lines 80 characters or longer,
grep `jot -s "" -b . 80`
The jot utility exits 0 on success, and >0 if an error occurs. The following diagnostic
messages deserve special explanation:
illegal or unsupported format '%s' The requested conversion format specifier for printf(3)
was not of the form
where ``?'' must be one of
range error in conversion A value to be printed fell outside the range of the data type
associated with the requested output format.
too many conversions More than one conversion format specifier has been supplied, but only
one is allowed.
ed(1), expand(1), rs(1), yes(1), printf(3), random(3)
BSD June 6, 1993 BSD