error catcher

main.c

@@ -16,28 +16,53 @@ int main(int argc, char *argv[]){
 	//PIN DIRECTION
 	
 	fd=open("/sys/class/gpio/chip0/gpio17/direction", O_WRONLY);	
+	if(fd<0)
+	{
+		perror("Error opening the gpio");
+		return -1;
+	}
 	write(fd, "out",3);
 	close(fd);
 
 	//WRITE VALUE
 	fd=open("/sys/class/gpio/chip0/gpio17/value", O_WRONLY);		
+	if(fd<0)
+	{
+		perror("Error opening the gpio");
+		return -1;
+	}
 	write(fd, "1",1);
 	close(fd);
 	sleep(10);
 	
 	fd=open("/sys/class/gpio/chip0/gpio17/value", O_WRONLY);		
+	if(fd<0)
+	{
+		perror("Error opening the gpio");
+		return -1;
+	}
 	write(fd, "0",1);
 	close(fd);
 	sleep(10);
 	
 
 	fd=open("/sys/class/gpio/chip0/gpio17/value", O_WRONLY);		
+	if(fd<0)
+	{
+		perror("Error opening the gpio");
+		return -1;
+	}
 	write(fd, "1",1);
 	close(fd);
 	sleep(10);
 	
 	//UNEXPORT
 	fd=open("/sys/class/gpio/chip0/gpio17/unexport", O_WRONLY);		
+	if(fd<0)
+	{
+		perror("Error opening the gpio");
+		return -1;
+	}
 	write(fd, "17",2);
 	close(fd);