Linux/PROCESSOR-SDK-AM335X: GPIO Driver

#include <stdio.h>
#include <string.h>
#include <stdlib.h>	// system()
#include <unistd.h>	// sleep()

int main()
{
	printf("LED Blink Project!\n");

	/* Set GPIO as output */
	system("echo 39 > /sys/class/gpio/export");
	system("echo \"out\" > /sys/class/gpio/gpio39/direction");
	system("echo 1 > /sys/class/gpio/gpio39/value");


	/* Set Button as input */
	system("echo 69 > /sys/class/gpio/export");
	system("echo \"in\" > /sys/class/gpio/gpio69/direction");
	system("echo \"falling\" > /sys/class/gpio/gpio69/edge");

	while(1)
	{
		if(1 == system("cat /sys/class/gpio/gpio69/value"))
		{
			system("echo 1 > /sys/class/gpio/gpio39/value");
			printf("LED : on!\n");
		}
		else
		{	
			system("echo 0 > /sys/class/gpio/gpio39/value");
			printf("LED : off!\n");
		}
	}
	return 0;	
}