//Leonardo Mendoza 26-sep-2026
#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>

//Prototypes
int gpio_export(const char *gpio);
int gpio_direction(int gpio, const char *direction);
int gpio_write(int gpio, int value);


int main(int argc, char *argv[])
{
	char pin[] = "17";
	gpio_export(pin);

	int fd;
	// DIRECTION	
	fd = open("/sys/class/gpio/chip0/gpio17/direction", O_WRONLY);
	if(fd<0)
	{
		perror("Error opening GPIO path");
		return -1;
	}
	write(fd, "out",3);
	close(fd);
	// VALUE	
	fd = open("/sys/class/gpio/chip0/gpio17/value", O_WRONLY);
	if(fd<0)
	{
		perror("Error opening GPIO path");
		return -1;
	}
	write(fd, "1", 1);
	close(fd);
	sleep(1);
	// Unexport
	fd = open("/sys/class/gpio/chip0/gpio17/value", O_WRONLY);
	if(fd<0)
	{
		perror("Error opening GPIO path");
		return -1;
	}
	write(fd, "0", 1);
	close(fd);
	sleep(1);


	fd = open("/sys/class/gpio/chip0/gpio17/value", O_WRONLY);
	if(fd<0)
	{
		perror("Error opening GPIO path");
		return -1;
	}
	write(fd, "1", 1);
	close(fd);
	sleep(1);

	fd = open("/sys/class/gpio/chip0/gpio17/unexport", O_WRONLY);
	if(fd<0)
	{
		perror("Error opening GPIO path");
		return -1;
	}
	write(fd, "17", 2);
	close(fd);


	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;
}

//Full functions
int gpio_export(const char *gpio)
{
    int fd;
	// EXPORT
	fd = open("/sys/class/gpio/chip0/export", O_WRONLY);
	if(fd<0)
	{
		perror("Error opening GPIO export path");
		return -1;
	}
	write(fd, gpio, strlen(gpio));
	close(fd);
	return 0;
}