[auxiliary vector] auxv

man:
getauxval

$ LD_SHOW_AUXV=1 /bin/ls

#include <sys/auxv.h>
#include <stdio.h>

int main() {
    // 1. Check for specific hardware features (simplified example)
    unsigned long hwcaps = getauxval(AT_HWCAP);
    
    // 2. Get the pointer to the 16 random bytes provided by kernel
    void *random_ptr = (void *)getauxval(AT_RANDOM);
    
    printf("Hardware Caps Bitmask: %lx\n", hwcaps);
    printf("Address of random seed: %p\n", random_ptr);
    
    return 0;
}