diff --git a/src/btop_shared.cpp b/src/btop_shared.cpp
index 0cafdfb..606c082 100644
--- a/src/btop_shared.cpp
+++ b/src/btop_shared.cpp
@@ -27,7 +27,7 @@ using namespace Tools;
 
 
 namespace Proc {
-	void proc_sorter(vector<proc_info>& proc_vec, string sorting, const bool reverse, const bool tree) {
+	void proc_sorter(vector<proc_info>& proc_vec, const string& sorting, const bool reverse, const bool tree) {
 		if (reverse) {
 			switch (v_index(sort_vector, sorting)) {
 			case 0: rng::stable_sort(proc_vec, rng::less{}, &proc_info::pid); 		break;
diff --git a/src/btop_shared.hpp b/src/btop_shared.hpp
index f61cdbb..bfec417 100644
--- a/src/btop_shared.hpp
+++ b/src/btop_shared.hpp
@@ -275,7 +275,7 @@ namespace Proc {
 	};
 
 	//* Sort vector of proc_info's
-	void proc_sorter(vector<proc_info>& proc_vec, string sorting, const bool reverse, const bool tree = false);
+	void proc_sorter(vector<proc_info>& proc_vec, const string& sorting, const bool reverse, const bool tree = false);
 
 	//* Recursive sort of process tree
 	void tree_sort(vector<tree_proc>& proc_vec, const string& sorting, const bool reverse, int& c_index, const int index_max, const bool collapsed = false);