#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>

int main(int argc, char *argv[]){
	int fd;
	// export
	fd = open("/sys/class/gpio/chip0/export", O_WRONLY);
	if(fd<0)
	{
		perror("Error opening the GPIO path");
		return -1;
	}

	write(fd,"17",2);
	close(fd);
	// pin direction
	fd = open("/sys/class/gpio/chip0/gpio17/direction", O_WRONLY);
	if(fd<0)
	{
		perror("Error opening the GPIO path");
		return -1;
	}
	write(fd,"out",3);
	close(fd);
	
	// pin value to 1
	fd = open("/sys/class/gpio/chip0/gpio17/value", O_WRONLY);
	if(fd<0)
	{
		perror("Error opening the GPIO path");
		return -1;
	}
	write(fd,"1",1);
	close(fd);
	sleep(1);
	// pin valu to 0
	fd = open("/sys/class/gpio/chip0/gpio17/value", O_WRONLY);
	if(fd<0)
	{
		perror("Error opening the GPIO path");
		return -1;
	}
	write(fd,"0",1);
	close(fd);
	sleep(1);
	// unexport
	fd = open("/sys/class/gpio/chip0/unexport", O_WRONLY);
	if(fd<0)
	{
		perror("Error opening the GPIO path");
		return -1;
	}
	write(fd,"17",2);
	close(fd);


	printf("Hello from Raspberry Pi!\n");
	printf("Number of arguments: %d\n", argc);
	printf("Program is reciving: %s\n", argv[0]);

	if(argc > 1 )
		printf("Argument: %s\n", argv[1]);
	return 0;
}