diff --git a/src/api.c b/src/api.c
index 06bd2c4..b6dec7e 100644
--- a/src/api.c
+++ b/src/api.c
@@ -165,6 +165,7 @@ void api_parse_exception(CURLresponse response, char *err) {
 		strcpy(err, json_tokener_errors[json_tok->err]);
 	}
 
+	json_object_put(json_obj);
 	json_tokener_free(json_tok);
 }
 
@@ -184,8 +185,9 @@ void * api_thread(void *arg) {
 
 	do { /* start thread mainloop */
 		CURLresponse response;
-		long int http_code, curl_code;
+		json_object *json_obj;
 		char *json_str;
+		long int http_code, curl_code;
 
 		/* initialize response */
 		response.data = NULL;
@@ -196,9 +198,11 @@ void * api_thread(void *arg) {
 			pthread_cond_wait(&ch->condition, &ch->mutex); /* sleep until new data has been read */
 		}
 		pthread_mutex_unlock(&ch->mutex);
-
-		json_str = json_object_to_json_string(api_json_tuples(ch, FALSE));
-		print(1, "JSON request body: %s", ch, json_str);
+		
+		json_obj = api_json_tuples(ch, FALSE);
+		json_str = json_object_to_json_string(json_obj);
+		
+		print(8, "JSON request body: %s", ch, json_str);
 
 		curl_easy_setopt(curl, CURLOPT_POSTFIELDS, json_str);
 		curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, curl_custom_write_callback);
@@ -208,7 +212,7 @@ void * api_thread(void *arg) {
 		curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &http_code);
 
 		if (curl_code == CURLE_OK && http_code == 200) { /* everything is ok */
-			print(1, "Request succeeded with code: %i", ch, http_code);
+			print(3, "Request succeeded with code: %i", ch, http_code);
 			queue_clear(&ch->queue);
 		}
 		else { /* error */
@@ -226,9 +230,8 @@ void * api_thread(void *arg) {
 		}
 
 		/* householding */
-		free(json_str);
-		// TODO free json objects
 		free(response.data);
+		json_object_put(json_obj);
 
 		pthread_testcancel(); /* test for cancelation request */
 	} while (opts.daemon);
diff --git a/src/main.c b/src/main.c
index cea71b5..4ba3cb7 100644
--- a/src/main.c
+++ b/src/main.c
@@ -34,8 +34,8 @@
 #include <getopt.h>
 
 #ifdef LOCAL
-	#include <microhttpd.h>
-	#include "local.h"
+#include <microhttpd.h>
+#include "local.h"
 #endif
 
 #include "main.h"
@@ -52,12 +52,12 @@
  * incl. function pointers
  */
 static protocol_t protocols[] = {
-	{"1wire",	"Dallas 1-Wire sensors (via OWFS)",	onewire_get,	onewire_init,	onewire_close,	MODE_SENSOR},
-//	{"obis",	"Plaintext OBIS",			obis_get,	obis_init,	obis_close,	MODE_SENSOR},
-	{"random",	"Random walk",				random_get,	random_init,	random_close,	MODE_SENSOR},
-	{"rawS0",	"S0 on RS232",				rawS0_get, 	rawS0_init,	rawS0_close,	MODE_METER},
-//	{"sml",		"Smart Meter Language",			sml_get,	sml_init,	sml_close,	MODE_SENSOR},
-//	{"fluksousb", 	"FluksoUSB board", 			flukso_get,	flukso_init,	flukso_close,	MODE_SENSOR},
+	{"1wire",	"Dallas 1-Wire sensors (via OWFS)",	onewire_get,	onewire_init,	onewire_close,	SENSOR},
+//	{"obis",	"Plaintext OBIS",			obis_get,	obis_init,	obis_close,	SENSOR},
+	{"random",	"Random walk",				random_get,	random_init,	random_close,	SENSOR},
+	{"rawS0",	"S0 on RS232",				rawS0_get, 	rawS0_init,	rawS0_close,	METER},
+//	{"sml",		"Smart Meter Language",			sml_get,	sml_init,	sml_close,	SENSOR},
+//	{"fluksousb", 	"FluksoUSB board", 			flukso_get,	flukso_init,	flukso_close,	SENSOR},
 	{NULL} /* stop condition for iterator */
 };
 
@@ -107,7 +107,7 @@ options_t opts = { /* setting default options */
 };
 
 /**
- * Print availble options and some other usefull information
+ * Print available options and some other usefull information
  */
 void usage(char * argv[]) {
 	char ** desc = long_options_descs;
@@ -242,13 +242,13 @@ void parse_options(int argc, char * argv[], options_t * opts) {
 }
 
 int parse_channels(char *filename, channel_t *chans) {
-	if (filename == NULL) {
-		fprintf(stderr, "No config file found! Please specify with --config!\n");
+	FILE *file = fopen(filename, "r"); /* open configuration */
+	
+	if (!filename) { /* nothing found */
+		print(-1, "No config file found! Please specify with --config!\n", NULL);
 		exit(EXIT_FAILURE);
 	}
 
-	FILE *file = fopen(filename, "r"); /* open configuration */
-
 	if (file == NULL) {
 		perror(filename); /* why didn't the file open? */
 		exit(EXIT_FAILURE);
@@ -354,7 +354,7 @@ void *read_thread(void *arg) {
 	do {
 		/**
 		 * Aquire reading,
-		 * may be blocking if mode == MODE_METER
+		 * may be blocking if interpreter == METER
 		 */
 		reading_t rd = ch->prot->read_func(ch->handle);
 
@@ -374,7 +374,7 @@ void *read_thread(void *arg) {
 			free(queue_str);
 		}
 
-		if (ch->prot->mode != MODE_METER) { /* for meters, the read_func call is blocking */
+		if (ch->prot->interpreter != METER) { /* for meters, the read_func call is blocking */
 			print(5, "Next reading in %i seconds", ch, ch->interval);
 			sleep(ch->interval); /* else sleep and restart aquisition */
 		}