[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]

Re: Extremely poor performance crunching random numbers under PIV-FC5

BankHacker wrote:

Please, could you tell me how to use the structure correctly? Thanks.

Any hint to continue will be appreciate.

Looks like initstate_r() is a big secret and the whole deal is poorly documented.


Here is my guess at the meaning of it all that appears to work:

    #include <stdio.h>
    #include <stdlib.h>
    #include <fcntl.h>

    int nRandom;
    struct random_data randomdataState;
    char szBufferState[1024];

    int main(int argc, char ** argv) {
        int n;

        int fd=open("/dev/urandom", O_RDONLY);
        if(fd<1) { perror("unable to open /dev/urandom"); return 1; }

        read(fd, szBufferState, sizeof(szBufferState));

initstate_r(*((int *)szBufferState), (szBufferState+sizeof(int)), sizeof(szBufferState)-sizeof(int), &randomdataState);

        for(n=0;n<2048;n++) {
                random_r(&randomdataState, &nRandom);
                printf("%d\n", nRandom);

        return (0);


Attachment: smime.p7s
Description: S/MIME Cryptographic Signature

[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]