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       bup-random - generate a stream of random output


       bup random [-S seed] [-f]


       bup random  produces  a  stream of pseudorandom output bytes to stdout.
       Note: the bytes are not generated using a cryptographic  algorithm  and
       should never be used for security.

       Note  that  the  stream  of  random  bytes will be identical every time
       bup random is run, unless you provide a different seed value.  This  is
       intentional:  the  purpose  of  this  program  is  to  be  able  to run
       repeatable tests on large amounts of data, so we  want  identical  data
       every time.

       bup random  generates  about  240 megabytes per second on a modern test
       system (Intel Core2), which is faster than you could achieve by reading
       data   from   most  disks.   Thus,  it  can  be  helpful  when  running


       the number of bytes of data to generate.
              Can be used with the suffices k, M, or G to indicate  kilobytes,
              megabytes, or gigabytes, respectively.

              use  the  given value to seed the pseudorandom number generator.
              The generated output stream will be identical for  every  stream
              seeded  with  the  same  value.   The default seed is 1.  A seed
              value of 0 is equivalent to 1.

              generate output even if stdout is  a  tty.   (Generating  random
              data  to  a tty is generally considered ill-advised, but you can
              do if you really want.)


             $ bup random 1k | sha1sum
             2108c55d0a2687c8dacf9192677c58437a55db71  -

             $ bup random -S1 1k | sha1sum
             2108c55d0a2687c8dacf9192677c58437a55db71  -

             $ bup random -S2 1k | sha1sum
             f71acb90e135d98dad7efc136e8d2cc30573e71a  -

             $ time bup random 1G >/dev/null
             Random: 1024 Mbytes, done.

             real   0m4.261s
             user   0m4.048s
             sys    0m0.172s

             $ bup random 1G | bup split -t --bench
             Random: 1024 Mbytes, done.
             bup: 1048576.00kbytes in 18.59 secs = 56417.78 kbytes/sec


       Part of the bup(1) suite.


       Avery Pennarun <>.