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JOT(1)                    BSD General Commands Manual                   JOT(1)

NAME
     jot -- print sequential or random data

SYNOPSIS
     jot [-cnr] [-b word] [-w word] [-s string] [-p precision] [reps [begin [end [s]]]]

DESCRIPTION
     The jot utility is used to print out increasing, decreasing, random, or redundant data, usually num-bers, numbers,
     bers, one per line.

     The following options are available:

     -r      Generate random data instead of the default sequential data.

     -b word
             Just print word repetitively.

     -w word
             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.

     -s string
             Print data separated by string.  Normally, newlines separate data.

     -n      Do not print the final newline normally appended to the output.

     -p precision
             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) conversion 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 - or as an empty string.  Any
     three of these arguments determines the fourth.  If four are specified and the given and computed val-ues values
     ues 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 a default of 1 or -1 if both begin and end are
     given.

     Defaults for the four arguments are, respectively, 100, 1, 100, and 1, except that when random 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 num-ber. number.
     ber.

     Random numbers are obtained through arc4random(3) when no seed is specified, and through random(3) when
     a seed is given.  When jot is asked to generate random integers or characters with begin and end values
     in the range of the random number generator function and no format is specified with one of the -w, -b,
     or -p options, jot will arrange for all the values in the range to appear in the output with an equal
     probability.  In all other cases be careful to ensure that the output format's rounding or truncation
     will not skew the distribution of output values in an unintended way.

     The name jot derives in part from iota, a function in APL.

EXIT STATUS
     The jot utility exits 0 on success, and >0 if an error occurs.

EXAMPLES
     The command
           jot - 1 10

     prints the integers from 1 to 10, while the command
           jot 21 -1 1.00

     prints 21 evenly spaced numbers increasing from -1 to 1.  The ASCII character set is generated with
           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, as in
           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`

DIAGNOSTICS
     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
           %[#][ ][{+,-}][0-9]*[.[0-9]*]?
     where ``?'' must be one of
           [l]{d,i,o,u,x}
     or
           {c,e,f,g,D,E,G,O,U,X}

     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.

SEE ALSO
     ed(1), expand(1), rs(1), seq(1), yes(1), arc4random(3), printf(3), random(3)

HISTORY
     The jot utility first appeared in 4.2BSD.

BSD                            February 19, 2010                           BSD