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JOT(1)                  FreeBSD 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 numbers, 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 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 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 number.

     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.

   Rounding and truncation
     The jot utility uses double precision floating point arithmetic
     internally.  Before printing a number, it is converted depending on the
     output format used.

     If no output format is specified or the output format is a floating point
     format (`E', `G', `e', `f', or `g'), the value is rounded using the
     printf(3) function, taking into account the requested precision.

     If the output format is an integer format (`D', `O', `U', `X', `c', `d',
     `i', `o', `u', or `x'), the value is converted to an integer value by
     truncation.

     As an illustration, consider the following command:

           $ jot 6 1 10 0.5
           1
           2
           2
           2
           3
           4

     By requesting an explicit precision of 1, the values generated before
     rounding can be seen.  The .5 values are rounded down if the integer part
     is even, up otherwise.

           $ jot -p 1 6 1 10 0.5
           1.0
           1.5
           2.0
           2.5
           3.0
           3.5

     By offsetting the values slightly, the values generated by the following
     command are always rounded down:

           $ jot -p 0 6 .9999999999 10 0.5
           1
           1
           2
           2
           3
           3

     Another way of achieving the same result is to force truncation by
     specifying an integer format:

           $ jot -w %d 6 1 10 0.5

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 truncating
     the output precision and a suitable choice of step size, as in
           jot -w %d - 9.5 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.

FreeBSD 11.0-PRERELEASE          June 2, 2010          FreeBSD 11.0-PRERELEASE

NAME | SYNOPSIS | DESCRIPTION | EXIT STATUS | EXAMPLES | DIAGNOSTICS | SEE ALSO | HISTORY

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