Re: random number generator oddity

[Scott Klement <midrange-l@xxxxxxxxxxxxxxxx>]

Hi Emily,

The ILE C function named rand() can be seeded by calling the srand() 
function.  If you don't call srand(), it will automatically seed the 
random number generator with a value of 1.  (Yes, that's right, it 
always picks 1 as the seed unless you tell it otherwise.)

Consider getting the current milliseconds from the clock (RPG example 
follows) and using that to seed the random number generator with a 
better value.

     ms = %div(%subdt(%timestamp():*MS):1000);

Then take the value in 'ms' and pass it to srand() to set the seed.

Or, better yet, don't use the rand() function.  The random number 
generator in C is notoriously bad...  instead, consider using CEERAN0 or 
even better, the crypto API for the random number (the name escapes me 
at the moment, but if you can't figure it out, let me know and I'll look 
it up.)


Emily Smith wrote:

> We have a program that uses 'rand' to generate  random numbers. I
> call this program requesting an eight byte number and receive a
> number 81239122. I sign off, and a coworker signs onto my workstation
. . . etc  . . .