Random max & min/max function C code

extern "C" {
  #include "stdlib.h"
}

void randomSeed(unsigned int seed)
{
  if (seed != 0) {
    srandom(seed);
  }
}

long random(long howbig)
{
  if (howbig == 0) {
    return 0;
  }
  return random() % howbig;
}

long random(long howsmall, long howbig)
{
  if (howsmall >= howbig) {
    return howsmall;
  }
  long diff = howbig - howsmall;
  return random(diff) + howsmall;
}