#include <stdio.h>
#include <sys/time.h>
#include <string.h>
#include <unistd.h>

#define CPUFREQ_FILE "/sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq"

char *estimate_MHz()
{
	FILE *fd = NULL;
	char buf[512], *ret;
	
	if ((fd = fopen(CPUFREQ_FILE, "r")) == NULL)
		return strdup("???");

	if (fgets(buf, sizeof(buf), fd) == NULL) {
		fclose(fd);
		return strdup("???");
	}
	fclose(fd);

	if ((ret = malloc(512)) == NULL)
		return strdup("???");
	
	snprintf(ret, 512, "%.1fMHz", (double)atoi(buf) / 1000.0);
	
	return ret;
}