gpio_direction function ok

main.c

@@ -1,6 +1,10 @@
 // Gerardo Marx 24/09/2026
 // gpio command tool
-//
+// eg. ./gpio 17 out 1
+//	   ./gpio 17 in 
+//	   ./gpio 17 blink 500(ms)
+
+
 #include <stdio.h>
 #include <fcntl.h>
 #include <unistd.h>
@@ -8,24 +12,18 @@
 
 // prototype functions
 int gpio_export(const char *gpio);
-int gpio_direction(int gpio, const char *direction); // this function
+int gpio_direction(const char *gpio, const char *direction); // this function
 int gpio_write(int gpio, int value);
 
 int main(int argc, char *argv[]){
 
 	int fd;
-	char pin[] = "17"; // get gpio number from argument
+	const char *pin = argv[1]; // get gpio number from argument
+	const char *dir = argv[2]; // get gpio direction from arguments
+							   //
 	gpio_export(pin); 
+	gpio_direction(pin, dir);
 	
-	// pin direction - convert into functions
-	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);
@@ -81,3 +79,32 @@ int gpio_export(const char *gpio){
 	close(fd);
 	return 0;
 }
+
+// gpio direction
+
+int gpio_direction(const char *gpio, const char *direction){
+	// pin direction - convert into functions
+	int fd;
+	char path[64];
+	snprintf(path, sizeof(path),
+			"/sys/class/gpio/chip0/gpio%s/direction", gpio);
+	fd = open(path, O_WRONLY); //gpio number
+	if(fd<0)
+	{
+		perror("Error opening the GPIO path");
+		return -1;
+	}
+	write(fd,direction,strlen(direction));
+	close(fd);
+	return 0;
+}
+
+
+
+
+
+
+
+
+
+