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=pod

=head1 NAME

openssl-rand,
rand - generate pseudo-random bytes

=head1 SYNOPSIS

B<openssl rand>
[B<-help>]
[B<-out> I<file>]
[B<-rand file...>]
[B<-writerand file>]
[B<-base64>]
[B<-hex>]
I<num>

=head1 DESCRIPTION

The B<rand> command outputs I<num> pseudo-random bytes after seeding
the random number generator once.  As in other B<openssl> command
line tools, PRNG seeding uses the file I<$HOME/>B<.rnd> or B<.rnd>
in addition to the files given in the B<-rand> option.  A new
I<$HOME>/B<.rnd> or B<.rnd> file will be written back if enough
seeding was obtained from these sources.

=head1 OPTIONS

=over 4

=item B<-help>

Print out a usage message.

=item B<-out file>

Write to I<file> instead of standard output.

=item B<-rand file...>

A file or files containing random data used to seed the random number
generator.
Multiple files can be specified separated by an OS-dependent character.
The separator is B<;> for MS-Windows, B<,> for OpenVMS, and B<:> for
all others.

=item [B<-writerand file>]

Writes random data to the specified I<file> upon exit.
This can be used with a subsequent B<-rand> flag.

=item B<-base64>

Perform base64 encoding on the output.

=item B<-hex>

Show the output as a hex string.

=back

=head1 SEE ALSO

L<RAND_bytes(3)>

=head1 COPYRIGHT

Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.

Licensed under the OpenSSL license (the "License").  You may not use
this file except in compliance with the License.  You can obtain a copy
in the file LICENSE in the source distribution or at
L<https://www.openssl.org/source/license.html>.

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