RAND_event()

=head1 NAME

RAND_add, RAND_seed, RAND_status, RAND_screen - add entropy to the PRNG

RAND_add, RAND_seed, RAND_status, RAND_event, RAND_screen - add

entropy to the PRNG

=head1 SYNOPSIS

 int  RAND_status(void);

 int  RAND_event(UINT iMsg, WPARAM wParam, LPARAM lParam);

 void RAND_screen(void);

=head1 DESCRIPTION

RAND_seed() is equivalent to RAND_add() when B<num == entropy>.

RAND_event() collects the entropy from Windows events such as mouse

movements and other user interaction. It should be called with the

B<iMsg>, B<wParam> and B<lParam> arguments of I<all> messages sent to

the window procedure. It will estimate the entropy contained in the

event message (if any), and add it to the PRNG. The program can then

process the messages as usual.

The RAND_screen() function is available for the convenience of Windows

programmers. It adds the current contents of the screen to the PRNG.

For applications that can catch Windows events, seeding the PRNG with

the parameters of B<WM_MOUSEMOVE> events is a significantly better

source of randomness. It should be noted that both methods cannot be

used on servers that run without user interaction.

For applications that can catch Windows events, seeding the PRNG by

calling RAND_event() is a significantly better source of

randomness. It should be noted that both methods cannot be used on

servers that run without user interaction.

=head1 RETURN VALUES

RAND_status() returns 1 if the PRNG has been seeded with enough data,

0 otherwise.

RAND_status() and RAND_event() return 1 if the PRNG has been seeded

with enough data, 0 otherwise.

The other functions do not return values.

RAND_seed() and RAND_screen() are available in all versions of SSLeay

and OpenSSL. RAND_add() and RAND_status() have been added in OpenSSL

0.9.5.

0.9.5, RAND_event() in OpenSSL 0.9.5a.

=cut