What is the environment variable HZ=100?
Your system would have an on-board timer, that ticks at a certain rate generating clock interrupts (ticks) per second. This rate is typically 100. HZ is a system variable denoting this rate.
You can look at <sys/param.h> and find the following on a Solaris system:
...
#define HZ ((int)_sysconf(_SC_CLK_TCK))
#define TICK (1000000000/(int)_sysconf(_SC_CLK_TCK)))
...
Thus, you can write a small piece of code that uses sysconf to get the value of HZ. Here's something that does the job:
#include <stdio.h>
#include <unistd.h>
#include <sys/param.h>
int
main()
{
long hz = 0;
if ((hz = sysconf(_SC_CLK_TCK)) < 0) {
perror("sysconf");
exit(1);
}
printf("HZ = %ld\n", hz);
exit(0);
}