When output in a file, destroy array, before the end. Avoid blc_channel trying to remove data

f_fftw_spectrum/f_fftw_spectrum.cpp

@@ -86,8 +86,15 @@ int main(int argc, char**argv){
             blc_eprint_cursor_up(rows_nb);
         }
     }
+
+   if (output.fd == -1){
+	output.~blc_array();
+   }
+
     fftwf_destroy_plan(fftw_plan);
     blc_eprint_cursor_down(rows_nb);
+
+    
     
     if (file) SYSTEM_ERROR_CHECK(fclose(file), -1, NULL);
     return EXIT_SUCCESS;