Index: uspace/lib/c/generic/str.c
===================================================================
--- uspace/lib/c/generic/str.c	(revision 4efeab5eba19b466b561564676dd7a05e0a2be56)
+++ uspace/lib/c/generic/str.c	(revision dce39b44550221926d8f74837e7882027f3ad94b)
@@ -518,4 +518,40 @@
 	return 0;
 
+}
+
+/** Test whether p is a prefix of s.
+ *
+ * Do a char-by-char comparison of two NULL-terminated strings
+ * and determine if p is a prefix of s.
+ *
+ * @param s The string in which to look
+ * @param p The string to check if it is a prefix of s
+ *
+ * @return true iff p is prefix of s else false
+ *
+ */
+bool str_test_prefix(const char *s, const char *p)
+{
+	wchar_t c1 = 0;
+	wchar_t c2 = 0;
+	
+	size_t off1 = 0;
+	size_t off2 = 0;
+
+	while (true) {
+		c1 = str_decode(s, &off1, STR_NO_LIMIT);
+		c2 = str_decode(p, &off2, STR_NO_LIMIT);
+		
+		if (c2 == 0)
+			return true;
+
+		if (c1 != c2)
+			return false;
+		
+		if (c1 == 0)
+			break;
+	}
+
+	return false;
 }