Ranbits
obtains
nbits
(rounded up to the nearest byte)
high-quality random bits from
random(4),
and emits them on standard output as an ASCII string.
The default output format is
datatot(3)
h
format:
lowercase hexadecimal with a
0x
prefix and an underscore every 32 bits.
The
--quick
option produces quick-and-dirty random bits:
instead of using the high-quality random bits from
/dev/random,
which may take some time to supply the necessary bits if
nbits
is large,
ranbits
uses
/dev/urandom,
which yields prompt results but lower-quality randomness.
The
--continuous
option uses
datatot(3)
x
output format, like
h
but without the underscores.
The
--bytes
option causes
nbits
to be interpreted as a byte count rather than a bit count.
There is an internal limit on
nbits,
currently 20000.
Without
--quick,
ranbits's
run time is difficult to predict.
A request for a large number of bits,
at a time when the system's entropy pool is low on randomness,
may take quite a while to satisfy.