error catcher in all fds

main.c

@@ -7,7 +7,7 @@ int main (int argc, char *argv[]){
 	// export 
 	fd = open("/sys/class/gpio/chip0/export", O_WRONLY);
 	if (fd < 0){
-		perror("Error opening the GPIO export path");
+		perror("Error opening the GPIO path");
 		return -1;
 	}
 	write(fd,"17", 2);
@@ -15,23 +15,39 @@ 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 path");
+		return -1;
+	}
 	write(fd,"out", 3);
 	close(fd);
 
 
 	//pin value
 	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);
 	
 	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);