diff --git a/src/main.c b/src/main.c
index 8bb8127..38cf9c9 100644
--- a/src/main.c
+++ b/src/main.c
@@ -4,6 +4,8 @@
 
 #define LOG_LEVEL LOG_LEVEL_DEBUG
 
+extern FILE* yyin;
+
 /**
  * @brief Log a debug message to inform about beginning exit procedures
  * 
@@ -13,6 +15,19 @@ void notify_exit(void)
     DEBUG("Exiting gemstone...");
 }
 
+/**
+ * @brief Closes File after compiling.
+ * 
+ */
+
+void close_file(void)
+{
+    if (NULL != yyin)
+    {
+        fclose(yyin);
+    }
+}
+
 /**
  * @brief Run compiler setup here
  * 
@@ -29,13 +44,34 @@ void setup(void)
     #endif
 
     // actual setup
-
+    
     DEBUG("finished starting up gemstone...");
 }
 
-int main(void) {
-    setup();
+int main(int argc, char *argv[]) {
 
+    setup();
+    atexit(close_file);
+    
+    // Check for file input as argument
+    if (2 != argc)
+    {
+        INFO("Usage: %s <filename>\n", argv[0]);
+        PANIC("No File could be found");
+    }
+    
+    // filename as first argument
+    char *filename = argv[1];
+
+    FILE *file = fopen(filename, "r");
+
+    if (NULL == file)
+    {
+        PANIC("File couldn't be opened!");
+    }
+    yyin = file;
+    
     yyparse();
+
     return 0;
 }